diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 8016dc52fd..d25ad260bb 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -77,6 +77,8 @@ jobs:
           java-version: 21
           cache: sbt
 
+      - uses: coursier/setup-action@v1
+
       - name: Check formatting
         if: matrix.scala == '2.13.14'
         run: sbt ++2.13.14 fmtCheck
@@ -87,6 +89,8 @@ jobs:
       - name: Build project
         run: sbt '++ ${{ matrix.scala }}' test
 
+      - uses: coursier/setup-action@v1
+
       - name: Check doc generation
         if: ${{ github.event_name == 'pull_request' }}
         run: sbt ++2.13.14 doc
@@ -229,11 +233,12 @@ jobs:
         java: [temurin@21]
     runs-on: ${{ matrix.os }}
     steps:
-      - name: Checkout current branch (full)
-        uses: actions/checkout@v4
+      - uses: actions/checkout@v4
         with:
           fetch-depth: 0
 
+      - uses: coursier/setup-action@v1
+
       - name: Setup Java (temurin@21)
         if: matrix.java == 'temurin@21'
         uses: actions/setup-java@v4
@@ -253,11 +258,14 @@ jobs:
         java: [temurin@8]
     runs-on: ${{ matrix.os }}
     steps:
-      - name: Checkout current branch (full)
-        uses: actions/checkout@v4
+      - uses: actions/checkout@v4
         with:
           fetch-depth: 0
 
+      - uses: coursier/setup-action@v1
+        with:
+          apps: sbt
+
       - name: Add Scoverage
         id: add_plugin
         run: sed -i -e '$aaddSbtPlugin("org.scoverage" % "sbt-scoverage" % "2.0.12")' project/plugins.sbt
@@ -286,11 +294,15 @@ jobs:
         java: [temurin@8]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: coursier/setup-action@v1
+        with:
+          apps: sbt
+
+      - uses: actions/checkout@v4
         with:
           path: zio-http
 
-      - uses: actions/setup-java@v2
+      - uses: actions/setup-java@v4
         with:
           distribution: temurin
           java-version: 11
@@ -305,7 +317,7 @@ jobs:
           cat > Main_CachedDateHeaderBenchmark.txt
           sbt -no-colors -v "zioHttpBenchmarks/jmh:run -i 3 -wi 3 -f1 -t1 CachedDateHeaderBenchmark" | grep -e "thrpt" -e "avgt" >> ../Main_CachedDateHeaderBenchmark.txt
 
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: Jmh_Main_CachedDateHeaderBenchmark
           path: Main_CachedDateHeaderBenchmark.txt
@@ -320,11 +332,15 @@ jobs:
         java: [temurin@8]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: coursier/setup-action@v1
+        with:
+          apps: sbt
+
+      - uses: actions/checkout@v4
         with:
           path: zio-http
 
-      - uses: actions/setup-java@v2
+      - uses: actions/setup-java@v4
         with:
           distribution: temurin
           java-version: 11
@@ -339,7 +355,7 @@ jobs:
           cat > Main_ClientBenchmark.txt
           sbt -no-colors -v "zioHttpBenchmarks/jmh:run -i 3 -wi 3 -f1 -t1 ClientBenchmark" | grep -e "thrpt" -e "avgt" >> ../Main_ClientBenchmark.txt
 
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: Jmh_Main_ClientBenchmark
           path: Main_ClientBenchmark.txt
@@ -354,11 +370,15 @@ jobs:
         java: [temurin@8]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: coursier/setup-action@v1
+        with:
+          apps: sbt
+
+      - uses: actions/checkout@v4
         with:
           path: zio-http
 
-      - uses: actions/setup-java@v2
+      - uses: actions/setup-java@v4
         with:
           distribution: temurin
           java-version: 11
@@ -373,7 +393,7 @@ jobs:
           cat > Main_CookieDecodeBenchmark.txt
           sbt -no-colors -v "zioHttpBenchmarks/jmh:run -i 3 -wi 3 -f1 -t1 CookieDecodeBenchmark" | grep -e "thrpt" -e "avgt" >> ../Main_CookieDecodeBenchmark.txt
 
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: Jmh_Main_CookieDecodeBenchmark
           path: Main_CookieDecodeBenchmark.txt
@@ -388,11 +408,15 @@ jobs:
         java: [temurin@8]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: coursier/setup-action@v1
+        with:
+          apps: sbt
+
+      - uses: actions/checkout@v4
         with:
           path: zio-http
 
-      - uses: actions/setup-java@v2
+      - uses: actions/setup-java@v4
         with:
           distribution: temurin
           java-version: 11
@@ -407,7 +431,7 @@ jobs:
           cat > Main_EndpointBenchmark.txt
           sbt -no-colors -v "zioHttpBenchmarks/jmh:run -i 3 -wi 3 -f1 -t1 EndpointBenchmark" | grep -e "thrpt" -e "avgt" >> ../Main_EndpointBenchmark.txt
 
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: Jmh_Main_EndpointBenchmark
           path: Main_EndpointBenchmark.txt
@@ -422,11 +446,15 @@ jobs:
         java: [temurin@8]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: coursier/setup-action@v1
+        with:
+          apps: sbt
+
+      - uses: actions/checkout@v4
         with:
           path: zio-http
 
-      - uses: actions/setup-java@v2
+      - uses: actions/setup-java@v4
         with:
           distribution: temurin
           java-version: 11
@@ -441,7 +469,7 @@ jobs:
           cat > Main_HttpCollectEval.txt
           sbt -no-colors -v "zioHttpBenchmarks/jmh:run -i 3 -wi 3 -f1 -t1 HttpCollectEval" | grep -e "thrpt" -e "avgt" >> ../Main_HttpCollectEval.txt
 
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: Jmh_Main_HttpCollectEval
           path: Main_HttpCollectEval.txt
@@ -456,11 +484,15 @@ jobs:
         java: [temurin@8]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: coursier/setup-action@v1
+        with:
+          apps: sbt
+
+      - uses: actions/checkout@v4
         with:
           path: zio-http
 
-      - uses: actions/setup-java@v2
+      - uses: actions/setup-java@v4
         with:
           distribution: temurin
           java-version: 11
@@ -475,7 +507,7 @@ jobs:
           cat > Main_HttpCombineEval.txt
           sbt -no-colors -v "zioHttpBenchmarks/jmh:run -i 3 -wi 3 -f1 -t1 HttpCombineEval" | grep -e "thrpt" -e "avgt" >> ../Main_HttpCombineEval.txt
 
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: Jmh_Main_HttpCombineEval
           path: Main_HttpCombineEval.txt
@@ -490,11 +522,15 @@ jobs:
         java: [temurin@8]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: coursier/setup-action@v1
+        with:
+          apps: sbt
+
+      - uses: actions/checkout@v4
         with:
           path: zio-http
 
-      - uses: actions/setup-java@v2
+      - uses: actions/setup-java@v4
         with:
           distribution: temurin
           java-version: 11
@@ -509,7 +545,7 @@ jobs:
           cat > Main_HttpNestedFlatMapEval.txt
           sbt -no-colors -v "zioHttpBenchmarks/jmh:run -i 3 -wi 3 -f1 -t1 HttpNestedFlatMapEval" | grep -e "thrpt" -e "avgt" >> ../Main_HttpNestedFlatMapEval.txt
 
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: Jmh_Main_HttpNestedFlatMapEval
           path: Main_HttpNestedFlatMapEval.txt
@@ -524,11 +560,15 @@ jobs:
         java: [temurin@8]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: coursier/setup-action@v1
+        with:
+          apps: sbt
+
+      - uses: actions/checkout@v4
         with:
           path: zio-http
 
-      - uses: actions/setup-java@v2
+      - uses: actions/setup-java@v4
         with:
           distribution: temurin
           java-version: 11
@@ -543,7 +583,7 @@ jobs:
           cat > Main_HttpRouteTextPerf.txt
           sbt -no-colors -v "zioHttpBenchmarks/jmh:run -i 3 -wi 3 -f1 -t1 HttpRouteTextPerf" | grep -e "thrpt" -e "avgt" >> ../Main_HttpRouteTextPerf.txt
 
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: Jmh_Main_HttpRouteTextPerf
           path: Main_HttpRouteTextPerf.txt
@@ -558,11 +598,15 @@ jobs:
         java: [temurin@8]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: coursier/setup-action@v1
+        with:
+          apps: sbt
+
+      - uses: actions/checkout@v4
         with:
           path: zio-http
 
-      - uses: actions/setup-java@v2
+      - uses: actions/setup-java@v4
         with:
           distribution: temurin
           java-version: 11
@@ -577,7 +621,7 @@ jobs:
           cat > Main_ProbeContentTypeBenchmark.txt
           sbt -no-colors -v "zioHttpBenchmarks/jmh:run -i 3 -wi 3 -f1 -t1 ProbeContentTypeBenchmark" | grep -e "thrpt" -e "avgt" >> ../Main_ProbeContentTypeBenchmark.txt
 
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: Jmh_Main_ProbeContentTypeBenchmark
           path: Main_ProbeContentTypeBenchmark.txt
@@ -592,11 +636,15 @@ jobs:
         java: [temurin@8]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: coursier/setup-action@v1
+        with:
+          apps: sbt
+
+      - uses: actions/checkout@v4
         with:
           path: zio-http
 
-      - uses: actions/setup-java@v2
+      - uses: actions/setup-java@v4
         with:
           distribution: temurin
           java-version: 11
@@ -611,7 +659,7 @@ jobs:
           cat > Main_SchemeDecodeBenchmark.txt
           sbt -no-colors -v "zioHttpBenchmarks/jmh:run -i 3 -wi 3 -f1 -t1 SchemeDecodeBenchmark" | grep -e "thrpt" -e "avgt" >> ../Main_SchemeDecodeBenchmark.txt
 
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: Jmh_Main_SchemeDecodeBenchmark
           path: Main_SchemeDecodeBenchmark.txt
@@ -626,11 +674,15 @@ jobs:
         java: [temurin@8]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: coursier/setup-action@v1
+        with:
+          apps: sbt
+
+      - uses: actions/checkout@v4
         with:
           path: zio-http
 
-      - uses: actions/setup-java@v2
+      - uses: actions/setup-java@v4
         with:
           distribution: temurin
           java-version: 11
@@ -645,7 +697,7 @@ jobs:
           cat > Main_ServerInboundHandlerBenchmark.txt
           sbt -no-colors -v "zioHttpBenchmarks/jmh:run -i 3 -wi 3 -f1 -t1 ServerInboundHandlerBenchmark" | grep -e "thrpt" -e "avgt" >> ../Main_ServerInboundHandlerBenchmark.txt
 
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: Jmh_Main_ServerInboundHandlerBenchmark
           path: Main_ServerInboundHandlerBenchmark.txt
@@ -660,11 +712,15 @@ jobs:
         java: [temurin@8]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v2
+      - uses: coursier/setup-action@v1
+        with:
+          apps: sbt
+
+      - uses: actions/checkout@v4
         with:
           path: zio-http
 
-      - uses: actions/setup-java@v2
+      - uses: actions/setup-java@v4
         with:
           distribution: temurin
           java-version: 11
@@ -679,7 +735,7 @@ jobs:
           cat > Main_UtilBenchmark.txt
           sbt -no-colors -v "zioHttpBenchmarks/jmh:run -i 3 -wi 3 -f1 -t1 UtilBenchmark" | grep -e "thrpt" -e "avgt" >> ../Main_UtilBenchmark.txt
 
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: Jmh_Main_UtilBenchmark
           path: Main_UtilBenchmark.txt
@@ -709,91 +765,91 @@ jobs:
         java: [temurin@8]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: Jmh_Main_CachedDateHeaderBenchmark
 
       - name: Format_Main_CachedDateHeaderBenchmark
         run: cat Main_CachedDateHeaderBenchmark.txt >> Main_benchmarks.txt
 
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: Jmh_Main_ClientBenchmark
 
       - name: Format_Main_ClientBenchmark
         run: cat Main_ClientBenchmark.txt >> Main_benchmarks.txt
 
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: Jmh_Main_CookieDecodeBenchmark
 
       - name: Format_Main_CookieDecodeBenchmark
         run: cat Main_CookieDecodeBenchmark.txt >> Main_benchmarks.txt
 
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: Jmh_Main_EndpointBenchmark
 
       - name: Format_Main_EndpointBenchmark
         run: cat Main_EndpointBenchmark.txt >> Main_benchmarks.txt
 
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: Jmh_Main_HttpCollectEval
 
       - name: Format_Main_HttpCollectEval
         run: cat Main_HttpCollectEval.txt >> Main_benchmarks.txt
 
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: Jmh_Main_HttpCombineEval
 
       - name: Format_Main_HttpCombineEval
         run: cat Main_HttpCombineEval.txt >> Main_benchmarks.txt
 
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: Jmh_Main_HttpNestedFlatMapEval
 
       - name: Format_Main_HttpNestedFlatMapEval
         run: cat Main_HttpNestedFlatMapEval.txt >> Main_benchmarks.txt
 
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: Jmh_Main_HttpRouteTextPerf
 
       - name: Format_Main_HttpRouteTextPerf
         run: cat Main_HttpRouteTextPerf.txt >> Main_benchmarks.txt
 
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: Jmh_Main_ProbeContentTypeBenchmark
 
       - name: Format_Main_ProbeContentTypeBenchmark
         run: cat Main_ProbeContentTypeBenchmark.txt >> Main_benchmarks.txt
 
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: Jmh_Main_SchemeDecodeBenchmark
 
       - name: Format_Main_SchemeDecodeBenchmark
         run: cat Main_SchemeDecodeBenchmark.txt >> Main_benchmarks.txt
 
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: Jmh_Main_ServerInboundHandlerBenchmark
 
       - name: Format_Main_ServerInboundHandlerBenchmark
         run: cat Main_ServerInboundHandlerBenchmark.txt >> Main_benchmarks.txt
 
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: Jmh_Main_UtilBenchmark
 
       - name: Format_Main_UtilBenchmark
         run: cat Main_UtilBenchmark.txt >> Main_benchmarks.txt
 
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
         with:
           path: zio-http
 
@@ -828,11 +884,11 @@ jobs:
           GITHUB_TOKEN: ${{secrets.ACTIONS_PAT}}
         run: sudo rm -rf *
 
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
         with:
           path: zio-http
 
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
         with:
           repository: khajavi/FrameworkBenchmarks
           path: FrameworkBenchMarks
@@ -885,7 +941,7 @@ jobs:
 
           if (( REQUESTS_PER_SECOND > PERFORMANCE_FLOOR )); then
             echo "Woohoo! Performance is good! $REQUESTS_PER_SECOND requests/sec exceeds the performance floor of $PERFORMANCE_FLOOR requests/sec."
-          else 
+          else
             echo "Performance benchmark failed with $REQUESTS_PER_SECOND req/sec! Performance must exceed $PERFORMANCE_FLOOR req/sec."
              exit 1
           fi
@@ -906,11 +962,11 @@ jobs:
           GITHUB_TOKEN: ${{secrets.ACTIONS_PAT}}
         run: sudo rm -rf *
 
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
         with:
           path: zio-http
 
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
         with:
           repository: khajavi/FrameworkBenchmarks
           path: FrameworkBenchMarks
@@ -963,7 +1019,7 @@ jobs:
 
           if (( REQUESTS_PER_SECOND > PERFORMANCE_FLOOR )); then
             echo "Woohoo! Performance is good! $REQUESTS_PER_SECOND requests/sec exceeds the performance floor of $PERFORMANCE_FLOOR requests/sec."
-          else 
+          else
             echo "Performance benchmark failed with $REQUESTS_PER_SECOND req/sec! Performance must exceed $PERFORMANCE_FLOOR req/sec."
              exit 1
           fi
diff --git a/.github/workflows/site.yml b/.github/workflows/site.yml
index 027da47ab4..f8bc4e9ef6 100644
--- a/.github/workflows/site.yml
+++ b/.github/workflows/site.yml
@@ -1,4 +1,4 @@
-# This file was autogenerated using `zio-sbt-website` via `sbt generateGithubWorkflow` 
+# This file was autogenerated using `zio-sbt-website` via `sbt generateGithubWorkflow`
 # task and should be included in the git repository. Please do not edit it manually.
 
 name: Website
@@ -23,6 +23,7 @@ jobs:
       uses: actions/checkout@v3.3.0
       with:
         fetch-depth: '0'
+    - uses: coursier/setup-action@v1
     - name: Setup Scala
       uses: actions/setup-java@v3.9.0
       with:
@@ -48,6 +49,7 @@ jobs:
         distribution: temurin
         java-version: 17
         check-latest: true
+    - uses: coursier/setup-action@v1
     - name: Setup NodeJs
       uses: actions/setup-node@v3
       with:
@@ -67,6 +69,7 @@ jobs:
       uses: actions/checkout@v4
       with:
         fetch-depth: '0'
+    - uses: coursier/setup-action@v1
     - name: Install libuv
       run: sudo apt-get update && sudo apt-get install -y libuv1-dev
     - name: Setup Scala
diff --git a/README.md b/README.md
index 5c8b92ec0a..73dfc6c7ea 100644
--- a/README.md
+++ b/README.md
@@ -43,7 +43,7 @@ Some of the key features of ZIO HTTP are:
 Setup via `build.sbt`:
 
 ```scala
-libraryDependencies += "dev.zio" %% "zio-http" % "3.0.0"
+libraryDependencies += "dev.zio" %% "zio-http" % "3.0.1"
 ```
 
 **NOTES ON VERSIONING:**
diff --git a/build.sbt b/build.sbt
index e2ad47a064..c35a4dd9fb 100644
--- a/build.sbt
+++ b/build.sbt
@@ -38,7 +38,10 @@ ThisBuild / githubWorkflowAddedJobs    :=
     WorkflowJob(
       id = "mima_check",
       name = "Mima Check",
-      steps = WorkflowStep.CheckoutFull +: WorkflowStep.SetupJava(List(JavaSpec.temurin("21"))) :+  WorkflowStep.Sbt(List("mimaChecks")),
+      steps = List(
+        WorkflowStep.Use(UseRef.Public("actions", "checkout", "v4"), Map("fetch-depth" -> "0")),
+        WorkflowStep.Use(UseRef.Public("coursier", "setup-action", "v1")),
+      ) ++ WorkflowStep.SetupJava(List(JavaSpec.temurin("21"))) :+ WorkflowStep.Sbt(List("mimaChecks")),
       cond = Option("${{ github.event_name == 'pull_request' }}"),
       javas = List(JavaSpec.temurin("21")),
     ),
@@ -75,6 +78,7 @@ ThisBuild / githubWorkflowPublish       :=
 //scala fix isn't available for scala 3 so ensure we only run the fmt check
 //using the latest scala 2.13
 ThisBuild / githubWorkflowBuildPreamble := Seq(
+  WorkflowStep.Use(UseRef.Public("coursier", "setup-action", "v1")),
   WorkflowStep.Run(
     name = Some("Check formatting"),
     commands = List(s"sbt ++${Scala213} fmtCheck"),
@@ -87,6 +91,7 @@ ThisBuild / githubWorkflowBuildPostamble :=
     "checkDocGeneration",
     "Check doc generation",
     List(
+      WorkflowStep.Use(UseRef.Public("coursier", "setup-action", "v1")),
       WorkflowStep.Run(
         commands = List(s"sbt ++${Scala213} doc"),
         name = Some("Check doc generation"),
diff --git a/docs/guides/testing-http-apps.md b/docs/guides/testing-http-apps.md
index 578d958ee2..5d462bcf36 100644
--- a/docs/guides/testing-http-apps.md
+++ b/docs/guides/testing-http-apps.md
@@ -117,12 +117,10 @@ object TestServerExampleSpec extends ZIOSpecDefault {
         fallbackResponse <- client.batched(Request.get(testRequest.url / "any"))
         fallbackBody     <- fallbackResponse.body.asString
       } yield assertTrue(helloBody == "Hey there!", fallbackBody == "fallback")
-    }.provideSome[Client with Driver](TestServer.layer)
+    }
   }.provide(
-    ZLayer.succeed(Server.Config.default.onAnyOpenPort),
+    TestServer.default,
     Client.default,
-    NettyDriver.customized,
-    ZLayer.succeed(NettyConfig.defaultWithFastShutdown),
   )
 }
 ```
diff --git a/docs/reference/handler.md b/docs/reference/handler.md
index 52bddff4e4..f4b43aedf5 100644
--- a/docs/reference/handler.md
+++ b/docs/reference/handler.md
@@ -612,6 +612,17 @@ In this example, the type of the handler before applying the `sandbox` operator
 
 Without the `sandbox` operator, the compiler would complain about the unhandled `Throwable` error.
 
+By default, sandboxed errors will result in a `500 Internal Server Error` response without a body. If you want to have all information about the error in the response body you can use a different (`ErrorResponseConfig`)[response/response.md#failure-responses-with-details] like `ErrorResponseConfig.debug`:
+
+```scala mdoc:compile-only
+import zio.http._
+import java.nio.file._
+
+Routes(
+   Method.GET / "file" ->
+           Handler.fromFile(Paths.get("file.txt").toFile).sandbox,
+   ) @@ ErrorResponseConfig.debug
+```
 ### Converting a `Handler` to an `Routes`
 
 The `Handler#toRoutes` operator, converts a handler to an `Routes` to be served by the `Server`. The following example, shows an HTTP application that serves a simple "Hello, World!" response for all types of incoming requests:
diff --git a/docs/reference/response/response.md b/docs/reference/response/response.md
index cb6a3ce842..f5d0dec5dc 100644
--- a/docs/reference/response/response.md
+++ b/docs/reference/response/response.md
@@ -188,6 +188,56 @@ val failedHandler = Handler.fail(new IOException())
 failedHandler.mapErrorCause(Response.fromCause)
 ```
 
+#### Failure Responses with Details
+
+By default, the `Response.fromThrowable` and `Response.fromCause` methods create a response with a status code only. If we want to include additional details in the response, we have to hand over a `ErrorResponseConfig`.
+
+```scala
+/**
+ * Configuration for the response generation
+ *
+ * @param withErrorBody
+ *   if true, includes the error message in the response body
+ * @param withStackTrace
+ *   if true, includes the stack trace in the response body
+ * @param maxStackTraceDepth
+ *   maximum number of stack trace lines to include in the response body. Set to
+ *   0 to include all lines.
+ * @param errorFormat
+ *   the preferred format for the error response. 
+ *   If the context in which the response is created has access to an Accept header,
+ *   the header will be used preferably to determine the format.
+ */
+final case class ErrorResponseConfig(
+  withErrorBody: Boolean = false,
+  withStackTrace: Boolean = false,
+  maxStackTraceDepth: Int = 10,
+  errorFormat: ErrorResponseConfig.ErrorFormat = ErrorResponseConfig.ErrorFormat.Html,
+)
+```
+
+This config can not only be used directly, but can also configure how ZIO-HTTP internally converts a `Cause` or `Throwable` to a `Response`.
+You can configure error responses globally by providing a custom `ErrorResponseConfig` via layer for example in the bootstrap of your application.
+Or you can apply the config locally to some routes via middleware.
+
+```scala mdoc
+import zio.http._
+
+object MyHttpApp extends ZIOAppDefault {
+  // Provide a custom ErrorResponseConfig via layer
+  // Equivalent to: val bootstrap = ErrorResponseConfig.configLayer(ErrorResponseConfig.debugConfig)
+  override val bootstrap: ZLayer[ZIOAppArgs, Any, Any] = ErrorResponseConfig.debugLayer
+
+  // Apply the ErrorResponseConfig.debug middleware to routes
+  // Equivalent to: val myRoutes = Handler.ok.toRoutes @@ ErrorResponseConfig.withConfig(ErrorResponseConfig.debugConfig)
+  val myRoutes = Handler.ok.toRoutes @@ ErrorResponseConfig.debug
+
+  override def run = ???
+}
+```
+
+The debug config will include the error message and full stack trace in the response body.
+
 :::note
 In many cases, it is more convenient to use the `sandbox` method to automatically convert all failures into a corresponding `Response`. But in some cases, to have more granular control over the error handling, we may want to use `Response.fromCause` and `Response.fromThrowable` directly.
 :::
diff --git a/project/BenchmarkWorkFlow.scala b/project/BenchmarkWorkFlow.scala
index dd2f01bde5..25cf7edaeb 100644
--- a/project/BenchmarkWorkFlow.scala
+++ b/project/BenchmarkWorkFlow.scala
@@ -35,13 +35,13 @@ object BenchmarkWorkFlow {
           commands = List("sudo rm -rf *"),
         ),
         WorkflowStep.Use(
-          UseRef.Public("actions", "checkout", s"v2"),
+          UseRef.Public("actions", "checkout", s"v4"),
           Map(
             "path" -> "zio-http",
           ),
         ),
         WorkflowStep.Use(
-          UseRef.Public("actions", "checkout", s"v2"),
+          UseRef.Public("actions", "checkout", s"v4"),
           Map(
             "repository" -> "khajavi/FrameworkBenchmarks",
             "path"       -> "FrameworkBenchMarks",
@@ -103,7 +103,7 @@ object BenchmarkWorkFlow {
 
               |if (( REQUESTS_PER_SECOND > PERFORMANCE_FLOOR )); then
               |  echo "Woohoo! Performance is good! $REQUESTS_PER_SECOND requests/sec exceeds the performance floor of $PERFORMANCE_FLOOR requests/sec."
-              |else 
+              |else
               |  echo "Performance benchmark failed with $REQUESTS_PER_SECOND req/sec! Performance must exceed $PERFORMANCE_FLOOR req/sec."
               |   exit 1
               |fi""".stripMargin,
diff --git a/project/Dependencies.scala b/project/Dependencies.scala
index 65007e599b..9bd09b8f72 100644
--- a/project/Dependencies.scala
+++ b/project/Dependencies.scala
@@ -5,7 +5,7 @@ object Dependencies {
   val NettyVersion                  = "4.1.112.Final"
   val NettyIncubatorVersion         = "0.0.25.Final"
   val ScalaCompactCollectionVersion = "2.12.0"
-  val ZioVersion                    = "2.1.9"
+  val ZioVersion                    = "2.1.11"
   val ZioCliVersion                 = "0.5.0"
   val ZioJsonVersion                = "0.7.1"
   val ZioParserVersion              = "0.1.10"
diff --git a/project/JmhBenchmarkWorkflow.scala b/project/JmhBenchmarkWorkflow.scala
index abb3a1b580..c49c17c5ea 100644
--- a/project/JmhBenchmarkWorkflow.scala
+++ b/project/JmhBenchmarkWorkflow.scala
@@ -11,7 +11,7 @@ object JmhBenchmarkWorkflow {
     Glob("zio-http-benchmarks/src/main/scala-2.13/**"),
     Glob("zio-http-benchmarks/src/main/scala/**")),scalaSources
     )
- 
+
   /**
    * Get zioHttpBenchmark file names
    */
@@ -45,7 +45,7 @@ object JmhBenchmarkWorkflow {
  def downloadArtifacts(branch: String, batchSize: Int) = groupedBenchmarks(batchSize).flatMap(l => {
     Seq(
       WorkflowStep.Use(
-        ref = UseRef.Public("actions", "download-artifact", "v3"),
+        ref = UseRef.Public("actions", "download-artifact", "v4"),
         Map(
           "name" -> s"Jmh_${branch}_${l.head}",
         ),
@@ -84,7 +84,7 @@ object JmhBenchmarkWorkflow {
       steps =  downloadArtifacts("Main", batchSize) ++
         Seq(
         WorkflowStep.Use(
-          UseRef.Public("actions", "checkout", "v2"),
+          UseRef.Public("actions", "checkout", "v4"),
           Map(
             "path" -> "zio-http"
           )
@@ -113,14 +113,15 @@ object JmhBenchmarkWorkflow {
       ),
       scalas = List(Scala213),
       steps = List(
+        WorkflowStep.Use(UseRef.Public("coursier", "setup-action","v1"), Map("apps" -> "sbt")),
         WorkflowStep.Use(
-          UseRef.Public("actions", "checkout", "v2"),
+          UseRef.Public("actions", "checkout", "v4"),
           Map(
             "path" -> "zio-http",
           ),
         ),
         WorkflowStep.Use(
-          UseRef.Public("actions", "setup-java", "v2"),
+          UseRef.Public("actions", "setup-java", "v4"),
           Map(
             "distribution" -> "temurin",
             "java-version" -> "11",
@@ -137,7 +138,7 @@ object JmhBenchmarkWorkflow {
           name = Some("Benchmark_Main"),
         ),
         WorkflowStep.Use(
-          UseRef.Public("actions", "upload-artifact", "v3"),
+          UseRef.Public("actions", "upload-artifact", "v4"),
           Map(
             "name" -> s"Jmh_Main_${l.head}",
             "path" -> s"Main_${l.head}.txt",
diff --git a/project/ScoverageWorkFlow.scala b/project/ScoverageWorkFlow.scala
index 54d677a727..e623d94a44 100644
--- a/project/ScoverageWorkFlow.scala
+++ b/project/ScoverageWorkFlow.scala
@@ -1,5 +1,5 @@
 import BuildHelper.{Scala213, ScoverageVersion}
-import sbtghactions.GenerativePlugin.autoImport.{WorkflowJob, WorkflowStep}
+import sbtghactions.GenerativePlugin.autoImport.{UseRef, WorkflowJob, WorkflowStep}
 
 object ScoverageWorkFlow {
   // TODO move plugins to plugins.sbt after scoverage's support for Scala 3
@@ -15,7 +15,8 @@ object ScoverageWorkFlow {
         name = "Unsafe Scoverage",
         scalas = List(Scala213),
         steps = List(
-          WorkflowStep.CheckoutFull,
+          WorkflowStep.Use(UseRef.Public("actions", "checkout", "v4"), Map("fetch-depth" -> "0")),
+          WorkflowStep.Use(UseRef.Public("coursier", "setup-action","v1"), Map("apps" -> "sbt")),
           WorkflowStep.Run(
             commands = List(s"sed -i -e '$$a${scoveragePlugin}' project/plugins.sbt"),
             id = Some("add_plugin"),
diff --git a/zio-http-gen/src/test/resources/ComponentAliasKey.scala b/zio-http-gen/src/test/resources/ComponentAliasKey.scala
new file mode 100644
index 0000000000..a9e41fa76c
--- /dev/null
+++ b/zio-http-gen/src/test/resources/ComponentAliasKey.scala
@@ -0,0 +1,9 @@
+package test.component
+
+import zio.prelude.Newtype
+import zio.schema.Schema
+import java.util.UUID
+
+object Key extends Newtype[UUID] {
+  implicit val schema: Schema[Key.Type] = Schema.primitive[UUID].transform(wrap, unwrap)
+}
\ No newline at end of file
diff --git a/zio-http-gen/src/test/resources/inline_schema_alias_only_as_key_schema.yaml b/zio-http-gen/src/test/resources/inline_schema_alias_only_as_key_schema.yaml
new file mode 100644
index 0000000000..6c23c0cf2e
--- /dev/null
+++ b/zio-http-gen/src/test/resources/inline_schema_alias_only_as_key_schema.yaml
@@ -0,0 +1,36 @@
+info:
+  title: Dummy Service
+  version: 0.0.1
+servers:
+  - url: http://127.0.0.1:5000/
+tags:
+  - name: Dummy_API
+paths:
+  /api/text_by_key:
+    get:
+      operationId: text_by_key
+      description: Get a dictionary mapping keys to text
+      responses:
+        "200":
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/ObjectWithDictionary'
+          description: OK
+openapi: 3.0.3
+components:
+  schemas:
+    Key:
+      type: string
+      format: uuid
+    ObjectWithDictionary:
+      type: object
+      required:
+        - dict
+      properties:
+        dict:
+          type: object
+          additionalProperties:
+            type: string
+            x-string-key-schema:
+              $ref: '#/components/schemas/Key'
diff --git a/zio-http-gen/src/test/scala/zio/http/gen/scala/CodeGenSpec.scala b/zio-http-gen/src/test/scala/zio/http/gen/scala/CodeGenSpec.scala
index e65ca03d81..16ba55d5d4 100644
--- a/zio-http-gen/src/test/scala/zio/http/gen/scala/CodeGenSpec.scala
+++ b/zio-http-gen/src/test/scala/zio/http/gen/scala/CodeGenSpec.scala
@@ -979,6 +979,29 @@ object CodeGenSpec extends ZIOSpecDefault {
           }
         }
       } @@ TestAspect.exceptScala3,
+      test("Schema with newtype only referenced as dictionary key") {
+        val openAPIString = stringFromResource("/inline_schema_alias_only_as_key_schema.yaml")
+
+        openApiFromYamlString(openAPIString) { oapi =>
+          codeGenFromOpenAPI(
+            oapi,
+            Config.default.copy(generateSafeTypeAliases = true),
+          ) { testDir =>
+            allFilesShouldBe(
+              testDir.toFile,
+              List(
+                "api/Text_by_key.scala",
+                "component/Key.scala",
+                "component/ObjectWithDictionary.scala",
+              ),
+            ) && fileShouldBe(
+              testDir,
+              "component/Key.scala",
+              "/ComponentAliasKey.scala",
+            )
+          }
+        }
+      } @@ TestAspect.exceptScala3,
       test("Generate all responses") {
         val oapi =
           OpenAPI(
diff --git a/zio-http-testkit/src/main/scala/zio/http/TestServer.scala b/zio-http-testkit/src/main/scala/zio/http/TestServer.scala
index 0bdd25dad9..d551f693dd 100644
--- a/zio-http-testkit/src/main/scala/zio/http/TestServer.scala
+++ b/zio-http-testkit/src/main/scala/zio/http/TestServer.scala
@@ -2,6 +2,9 @@ package zio.http
 
 import zio._
 
+import zio.http.netty.NettyConfig
+import zio.http.netty.server.NettyDriver
+
 /**
  * Enables tests that make calls against "localhost" with user-specified
  * Behavior/Responses.
@@ -136,4 +139,11 @@ object TestServer {
       } yield TestServer(driver, result.port)
     }
 
+  val default: ZLayer[Any, Nothing, Server with TestServer] = ZLayer.make[Server with TestServer][Nothing](
+    TestServer.layer.orDie,
+    ZLayer.succeed(Server.Config.default.onAnyOpenPort),
+    NettyDriver.customized.orDie,
+    ZLayer.succeed(NettyConfig.defaultWithFastShutdown),
+  )
+
 }
diff --git a/zio-http-testkit/src/test/scala/zio/http/TestServerSpec.scala b/zio-http-testkit/src/test/scala/zio/http/TestServerSpec.scala
index 084d9197e2..a6b90871bb 100644
--- a/zio-http-testkit/src/test/scala/zio/http/TestServerSpec.scala
+++ b/zio-http-testkit/src/test/scala/zio/http/TestServerSpec.scala
@@ -37,8 +37,8 @@ object TestServerSpec extends ZIOHttpSpec {
           )
       } yield assertTrue(status(response1) == Status.Ok) &&
         assertTrue(status(response2) == Status.InternalServerError)
-    }.provideSome[Client with Driver](
-      TestServer.layer,
+    }.provideSome[Client](
+      TestServer.default,
       Scope.default,
     ),
     suite("Exact Request=>Response version")(
@@ -83,8 +83,8 @@ object TestServerSpec extends ZIOHttpSpec {
         } yield assertTrue(status(finalResponse) == Status.NotFound)
       },
     )
-      .provideSome[Client with Driver](
-        TestServer.layer,
+      .provideSome[Client](
+        TestServer.default,
         Scope.default,
       ),
     test("add routes to the server") {
@@ -102,15 +102,12 @@ object TestServerSpec extends ZIOHttpSpec {
         fallbackResponse <- client(Request.get(testRequest.url / "any"))
         fallbackBody     <- fallbackResponse.body.asString
       } yield assertTrue(helloBody == "Hey there!", fallbackBody == "fallback")
-    }.provideSome[Client with Driver](
-      TestServer.layer,
+    }.provideSome[Client](
+      TestServer.default,
       Scope.default,
     ),
   ).provide(
-    ZLayer.succeed(Server.Config.default.onAnyOpenPort),
     Client.default,
-    NettyDriver.customized,
-    ZLayer.succeed(NettyConfig.defaultWithFastShutdown),
   )
 
   private def requestToCorrectPort =
diff --git a/zio-http/jvm/src/main/scala/zio/http/netty/client/ClientSSLConverter.scala b/zio-http/jvm/src/main/scala/zio/http/netty/client/ClientSSLConverter.scala
index 6df29da1db..7a3b3e0c94 100644
--- a/zio-http/jvm/src/main/scala/zio/http/netty/client/ClientSSLConverter.scala
+++ b/zio-http/jvm/src/main/scala/zio/http/netty/client/ClientSSLConverter.scala
@@ -18,7 +18,7 @@ package zio.http.netty.client
 
 import java.io.{File, FileInputStream, InputStream}
 import java.security.KeyStore
-import javax.net.ssl.TrustManagerFactory
+import javax.net.ssl.{KeyManagerFactory, TrustManagerFactory}
 
 import scala.util.Using
 
@@ -31,6 +31,39 @@ import zio.http.ClientSSLConfig
 import io.netty.handler.ssl.util.InsecureTrustManagerFactory
 import io.netty.handler.ssl.{SslContext, SslContextBuilder}
 private[netty] object ClientSSLConverter {
+  private def keyManagerTrustManagerToSslContext(
+    keyManagerInfo: Option[(String, InputStream, Option[Secret])],
+    trustManagerInfo: Option[(String, InputStream, Option[Secret])],
+    sslContextBuilder: SslContextBuilder,
+  ): SslContextBuilder = {
+    val mkeyManagerFactory =
+      keyManagerInfo.map { case (keyStoreType, inputStream, maybePassword) =>
+        val keyStore          = KeyStore.getInstance(keyStoreType)
+        val keyManagerFactory = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm)
+        val password          = maybePassword.map(_.value.toArray).orNull
+
+        keyStore.load(inputStream, password)
+        keyManagerFactory.init(keyStore, password)
+        keyManagerFactory
+      }
+
+    val mtrustManagerFactory =
+      trustManagerInfo.map { case (keyStoreType, inputStream, maybePassword) =>
+        val keyStore            = KeyStore.getInstance(keyStoreType)
+        val trustManagerFactory = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm)
+        val password            = maybePassword.map(_.value.toArray).orNull
+
+        keyStore.load(inputStream, password)
+        trustManagerFactory.init(keyStore)
+        trustManagerFactory
+      }
+
+    var bldr = SslContextBuilder.forClient()
+    mkeyManagerFactory.foreach(kmf => bldr = bldr.keyManager(kmf))
+    mtrustManagerFactory.foreach(tmf => bldr = bldr.trustManager(tmf))
+    bldr
+  }
+
   private def trustStoreToSslContext(
     trustStoreStream: InputStream,
     trustStorePassword: Secret,
@@ -78,6 +111,41 @@ private[netty] object ClientSSLConverter {
     case ClientSSLConfig.FromTrustStoreFile(trustStorePath, trustStorePassword)                               =>
       val trustStoreStream = new FileInputStream(trustStorePath)
       trustStoreToSslContext(trustStoreStream, trustStorePassword, sslContextBuilder)
+    case ClientSSLConfig.FromJavaxNetSsl(
+          keyManagerKeyStoreType,
+          keyManagerSource,
+          keyManagerPassword,
+          trustManagerKeyStoreType,
+          trustManagerSource,
+          trustManagerPassword,
+        ) =>
+      val keyManagerInfo =
+        keyManagerSource match {
+          case ClientSSLConfig.FromJavaxNetSsl.File(path)     =>
+            Option(new FileInputStream(path)).map(inputStream =>
+              (keyManagerKeyStoreType, inputStream, keyManagerPassword),
+            )
+          case ClientSSLConfig.FromJavaxNetSsl.Resource(path) =>
+            Option(getClass.getClassLoader.getResourceAsStream(path)).map(inputStream =>
+              (keyManagerKeyStoreType, inputStream, keyManagerPassword),
+            )
+          case ClientSSLConfig.FromJavaxNetSsl.Empty          => None
+        }
+
+      val trustManagerInfo =
+        trustManagerSource match {
+          case ClientSSLConfig.FromJavaxNetSsl.File(path)     =>
+            Option(new FileInputStream(path)).map(inputStream =>
+              (trustManagerKeyStoreType, inputStream, trustManagerPassword),
+            )
+          case ClientSSLConfig.FromJavaxNetSsl.Resource(path) =>
+            Option(getClass.getClassLoader.getResourceAsStream(path)).map(inputStream =>
+              (trustManagerKeyStoreType, inputStream, trustManagerPassword),
+            )
+          case ClientSSLConfig.FromJavaxNetSsl.Empty          => None
+        }
+
+      keyManagerTrustManagerToSslContext(keyManagerInfo, trustManagerInfo, sslContextBuilder)
   }
 
   def toNettySSLContext(sslConfig: ClientSSLConfig): SslContext = {
diff --git a/zio-http/jvm/src/test/scala/zio/http/ClientHttpsSpec.scala b/zio-http/jvm/src/test/scala/zio/http/ClientHttpsSpec.scala
index 97d5810d7c..fcdb1842e2 100644
--- a/zio-http/jvm/src/test/scala/zio/http/ClientHttpsSpec.scala
+++ b/zio-http/jvm/src/test/scala/zio/http/ClientHttpsSpec.scala
@@ -18,18 +18,14 @@ package zio.http
 
 import zio._
 import zio.test.Assertion._
-import zio.test.TestAspect.{ignore, nonFlaky}
+import zio.test.TestAspect.nonFlaky
 import zio.test.{TestAspect, assertZIO}
 
 import zio.http.netty.NettyConfig
 import zio.http.netty.client.NettyClientDriver
 
-object ClientHttpsSpec extends ZIOHttpSpec {
-
-  val sslConfig = ClientSSLConfig.FromTrustStoreResource(
-    trustStorePath = "truststore.jks",
-    trustStorePassword = "changeit",
-  )
+abstract class ClientHttpsSpecBase extends ZIOHttpSpec {
+  val sslConfig: ClientSSLConfig
 
   val zioDev =
     URL.decode("https://zio.dev").toOption.get
@@ -37,7 +33,7 @@ object ClientHttpsSpec extends ZIOHttpSpec {
   val badRequest =
     URL
       .decode(
-        "https://www.whatissslcertificate.com/google-has-made-the-list-of-untrusted-providers-of-digital-certificates/",
+        "https://httpbin.org/status/400",
       )
       .toOption
       .get
@@ -57,7 +53,7 @@ object ClientHttpsSpec extends ZIOHttpSpec {
     test("should respond as Bad Request") {
       val actual = Client.batched(Request.get(badRequest)).map(_.status)
       assertZIO(actual)(equalTo(Status.BadRequest))
-    } @@ ignore,
+    },
     test("should throw DecoderException for handshake failure") {
       val actual = Client.batched(Request.get(untrusted)).exit
       assertZIO(actual)(
@@ -69,7 +65,7 @@ object ClientHttpsSpec extends ZIOHttpSpec {
           ),
         ),
       )
-    } @@ nonFlaky(20) @@ ignore,
+    } @@ nonFlaky(20),
   )
     .provideShared(
       ZLayer.succeed(ZClient.Config.default.ssl(sslConfig)),
@@ -83,3 +79,20 @@ object ClientHttpsSpec extends ZIOHttpSpec {
     ZLayer.succeed(NettyConfig.defaultWithFastShutdown),
   )
 }
+
+object ClientHttpsSpec extends ClientHttpsSpecBase {
+
+  val sslConfig = ClientSSLConfig.FromTrustStoreResource(
+    trustStorePath = "truststore.jks",
+    trustStorePassword = "changeit",
+  )
+}
+
+object ClientHttpsFromJavaxNetSslSpec extends ClientHttpsSpecBase {
+
+  val sslConfig =
+    ClientSSLConfig.FromJavaxNetSsl
+      .builderWithTrustManagerResource("trustStore.jks")
+      .trustManagerPassword("changeit")
+      .build()
+}
diff --git a/zio-http/jvm/src/test/scala/zio/http/RouteSpec.scala b/zio-http/jvm/src/test/scala/zio/http/RouteSpec.scala
index a0fc0f8b0a..4d195e2f14 100644
--- a/zio-http/jvm/src/test/scala/zio/http/RouteSpec.scala
+++ b/zio-http/jvm/src/test/scala/zio/http/RouteSpec.scala
@@ -135,6 +135,12 @@ object RouteSpec extends ZIOHttpSpec {
           bodyString <- response.body.asString
         } yield assertTrue(extractStatus(response) == Status.InternalServerError, bodyString == "error")
       },
+      test("handleErrorCause should pass through responses in error channel of handled routes") {
+        val route        = Method.GET / "endpoint" -> handler { (_: Request) => ZIO.fail(Response.ok) }
+        val errorHandled = route.handleErrorCause(_ => Response.text("error").status(Status.InternalServerError))
+        val request      = Request.get(URL.decode("/endpoint").toOption.get)
+        errorHandled.toRoutes.runZIO(request).map(response => assertTrue(extractStatus(response) == Status.Ok))
+      },
       test("handleErrorCauseZIO should handle defects") {
         val route        = Method.GET / "endpoint" -> handler { (_: Request) => ZIO.dieMessage("hmm...") }
         val errorHandled =
@@ -145,6 +151,18 @@ object RouteSpec extends ZIOHttpSpec {
           bodyString <- response.body.asString
         } yield assertTrue(extractStatus(response) == Status.InternalServerError, bodyString == "error")
       },
+      test("handleErrorCauseZIO should pass through responses in error channel of handled routes") {
+        val route   = Method.GET / "endpoint" -> handler { (_: Request) => ZIO.fail(Response.ok) }
+        val request = Request.get(URL.decode("/endpoint").toOption.get)
+        for {
+          ref <- Ref.make(false)
+          errorHandled = route.handleErrorCauseZIO(_ =>
+            ref.set(true) *> ZIO.succeed(Response.text("error").status(Status.InternalServerError)),
+          )
+          response <- errorHandled.toRoutes.runZIO(request)
+          refValue <- ref.get
+        } yield assertTrue(extractStatus(response) == Status.Ok, !refValue)
+      },
       test("handleErrorRequestCause should handle defects") {
         val route        = Method.GET / "endpoint" -> handler { (_: Request) => ZIO.dieMessage("hmm...") }
         val errorHandled =
@@ -155,6 +173,13 @@ object RouteSpec extends ZIOHttpSpec {
           bodyString <- response.body.asString
         } yield assertTrue(extractStatus(response) == Status.InternalServerError, bodyString == "error")
       },
+      test("handleErrorRequestCause should pass through responses in error channel of handled routes") {
+        val route        = Method.GET / "endpoint" -> handler { (_: Request) => ZIO.fail(Response.ok) }
+        val errorHandled =
+          route.handleErrorRequestCause((_, _) => Response.text("error").status(Status.InternalServerError))
+        val request      = Request.get(URL.decode("/endpoint").toOption.get)
+        errorHandled.toRoutes.runZIO(request).map(response => assertTrue(extractStatus(response) == Status.Ok))
+      },
       test("handleErrorRequestCauseZIO should handle defects") {
         val route        = Method.GET / "endpoint" -> handler { (_: Request) => ZIO.dieMessage("hmm...") }
         val errorHandled = route.handleErrorRequestCauseZIO((_, _) =>
@@ -166,6 +191,18 @@ object RouteSpec extends ZIOHttpSpec {
           bodyString <- response.body.asString
         } yield assertTrue(extractStatus(response) == Status.InternalServerError, bodyString == "error")
       },
+      test("handleErrorRequestCauseZIO should pass through responses in error channel of handled routes") {
+        val route   = Method.GET / "endpoint" -> handler { (_: Request) => ZIO.fail(Response.ok) }
+        val request = Request.get(URL.decode("/endpoint").toOption.get)
+        for {
+          ref <- Ref.make(false)
+          errorHandled = route.handleErrorRequestCauseZIO((_, _) =>
+            ref.set(true) *> ZIO.succeed(Response.text("error").status(Status.InternalServerError)),
+          )
+          response <- errorHandled.toRoutes.runZIO(request)
+          refValue <- ref.get
+        } yield assertTrue(extractStatus(response) == Status.Ok, !refValue)
+      },
       test(
         "Routes with context can eliminate environment type partially when elimination produces intersection type environment",
       ) {
diff --git a/zio-http/jvm/src/test/scala/zio/http/codec/PathCodecSpec.scala b/zio-http/jvm/src/test/scala/zio/http/codec/PathCodecSpec.scala
index 8c00e783ba..fc5026061b 100644
--- a/zio-http/jvm/src/test/scala/zio/http/codec/PathCodecSpec.scala
+++ b/zio-http/jvm/src/test/scala/zio/http/codec/PathCodecSpec.scala
@@ -194,17 +194,14 @@ object PathCodecSpec extends ZIOHttpSpec {
         test("/users") {
           val codec = PathCodec.empty / PathCodec.literal("users")
 
-          assertTrue(
-            codec.segments ==
-              Chunk(SegmentCodec.empty, SegmentCodec.literal("users")),
-          )
+          assertTrue(codec.segments == Chunk(SegmentCodec.literal("users")))
         },
       ),
       suite("render")(
         test("empty") {
           val codec = PathCodec.empty
 
-          assertTrue(codec.render == "")
+          assertTrue(codec.render == "/")
         },
         test("/users") {
           val codec = PathCodec.empty / PathCodec.literal("users")
diff --git a/zio-http/jvm/src/test/scala/zio/http/endpoint/AuthSpec.scala b/zio-http/jvm/src/test/scala/zio/http/endpoint/AuthSpec.scala
index 6b60f20c0a..4d93dff8cf 100644
--- a/zio-http/jvm/src/test/scala/zio/http/endpoint/AuthSpec.scala
+++ b/zio-http/jvm/src/test/scala/zio/http/endpoint/AuthSpec.scala
@@ -154,7 +154,7 @@ object AuthSpec extends ZIOSpecDefault {
         },
         test("Auth basic or bearer with context and endpoint client") {
           val endpoint =
-            Endpoint(Method.GET / "test" / "multiAuth")
+            Endpoint(Method.GET / "multiAuth")
               .out[String](MediaType.text.`plain`)
               .auth(AuthType.Basic | AuthType.Bearer)
           val routes   =
@@ -188,7 +188,7 @@ object AuthSpec extends ZIOSpecDefault {
           } yield assertTrue(responseBasic == "admin" && responseBearer == "bearer-admin")
         },
         test("Auth from query parameter with context and endpoint client") {
-          val endpoint = Endpoint(Method.GET / "test" / "query")
+          val endpoint = Endpoint(Method.GET / "query")
             .out[String](MediaType.text.`plain`)
             .auth(AuthType.Custom(HttpCodec.query[String]("token")))
           val routes   =
@@ -214,7 +214,7 @@ object AuthSpec extends ZIOSpecDefault {
         },
         test("Auth with context and endpoint client with path parameter") {
           val endpoint =
-            Endpoint(Method.GET / "test" / int("a")).out[String](MediaType.text.`plain`).auth(AuthType.Basic)
+            Endpoint(Method.GET / int("a")).out[String](MediaType.text.`plain`).auth(AuthType.Basic)
           val routes   =
             Routes(
               endpoint.implementHandler(handler((_: Int) => withContext((ctx: AuthContext) => ctx.value))),
diff --git a/zio-http/jvm/src/test/scala/zio/http/endpoint/ServerSentEventEndpointSpec.scala b/zio-http/jvm/src/test/scala/zio/http/endpoint/ServerSentEventEndpointSpec.scala
index 77a14a4f4e..e5816e22e8 100644
--- a/zio-http/jvm/src/test/scala/zio/http/endpoint/ServerSentEventEndpointSpec.scala
+++ b/zio-http/jvm/src/test/scala/zio/http/endpoint/ServerSentEventEndpointSpec.scala
@@ -14,6 +14,7 @@ import zio.schema.{DeriveSchema, Schema}
 
 import zio.http._
 import zio.http.codec.HttpCodec
+import zio.http.netty.NettyConfig
 
 object ServerSentEventEndpointSpec extends ZIOHttpSpec {
 
@@ -40,13 +41,14 @@ object ServerSentEventEndpointSpec extends ZIOHttpSpec {
       : Invocation[Unit, Unit, ZNothing, ZStream[Any, Nothing, ServerSentEvent[String]], AuthType.None] =
       sseEndpoint(())
 
-    def client(port: Int): ZIO[Scope, Throwable, Chunk[ServerSentEvent[String]]] =
-      (for {
+    def client(port: Int): ZIO[Client, Throwable, Chunk[ServerSentEvent[String]]] = ZIO.scoped {
+      for {
         client <- ZIO.service[Client]
         executor = EndpointExecutor(client, locator(port))
         stream <- executor(invocation)
         events <- stream.take(5).runCollect
-      } yield events).provideSome[Scope](ZClient.default)
+      } yield events
+    }
   }
 
   object JsonPayload {
@@ -77,13 +79,14 @@ object ServerSentEventEndpointSpec extends ZIOHttpSpec {
       : Invocation[Unit, Unit, ZNothing, ZStream[Any, Nothing, ServerSentEvent[Payload]], AuthType.None] =
       sseEndpoint(())
 
-    def client(port: Int): ZIO[Scope, Throwable, Chunk[ServerSentEvent[Payload]]] =
-      (for {
+    def client(port: Int): ZIO[Client, Throwable, Chunk[ServerSentEvent[Payload]]] = ZIO.scoped {
+      for {
         client <- ZIO.service[Client]
         executor = EndpointExecutor(client, locator(port))
         stream <- executor(invocation)
         events <- stream.take(5).runCollect
-      } yield events).provideSome[Scope](ZClient.default)
+      } yield events
+    }
   }
 
   override def spec: Spec[TestEnvironment with Scope, Any] =
@@ -95,7 +98,7 @@ object ServerSentEventEndpointSpec extends ZIOHttpSpec {
           port   <- ZIO.serviceWithZIO[Server](_.port)
           events <- client(port)
         } yield assertTrue(events.size == 5 && events.forall(event => Try(ISO_LOCAL_TIME.parse(event.data)).isSuccess))
-      }.provideSome[Scope](Server.defaultWithPort(0)),
+      },
       test("Send and receive ServerSentEvent with json payload") {
         import JsonPayload._
         for {
@@ -103,6 +106,14 @@ object ServerSentEventEndpointSpec extends ZIOHttpSpec {
           port   <- ZIO.serviceWithZIO[Server](_.port)
           events <- client(port)
         } yield assertTrue(events.size == 5 && events.forall(event => Try(event.data.timeStamp).isSuccess))
-      }.provideSome[Scope](Server.defaultWithPort(0)),
-    ) @@ TestAspect.withLiveClock
+      },
+    )
+      .provideSomeLayer[Client & Server.Config & NettyConfig](Server.customized)
+      .provideShared(
+        Client.live,
+        ZLayer.succeed(Server.Config.default.port(0)),
+        ZLayer.succeed(NettyConfig.defaultWithFastShutdown),
+        ZLayer.succeed(ZClient.Config.default),
+        DnsResolver.default,
+      ) @@ TestAspect.withLiveClock
 }
diff --git a/zio-http/jvm/src/test/scala/zio/http/endpoint/openapi/OpenAPIGenSpec.scala b/zio-http/jvm/src/test/scala/zio/http/endpoint/openapi/OpenAPIGenSpec.scala
index 06e00af622..73ceede3a0 100644
--- a/zio-http/jvm/src/test/scala/zio/http/endpoint/openapi/OpenAPIGenSpec.scala
+++ b/zio-http/jvm/src/test/scala/zio/http/endpoint/openapi/OpenAPIGenSpec.scala
@@ -10,8 +10,8 @@ import zio.schema.{DeriveSchema, Schema}
 
 import zio.http.Method.{GET, POST}
 import zio.http._
-import zio.http.codec.PathCodec.string
-import zio.http.codec.{ContentCodec, Doc, HttpCodec}
+import zio.http.codec.PathCodec.{empty, string}
+import zio.http.codec._
 import zio.http.endpoint._
 
 object OpenAPIGenSpec extends ZIOSpecDefault {
@@ -180,6 +180,13 @@ object OpenAPIGenSpec extends ZIOSpecDefault {
       .out[SimpleOutputBody]
       .outError[NotFoundError](Status.NotFound)
 
+  private val queryParamOptEndpoint =
+    Endpoint(GET / "withQuery")
+      .in[SimpleInputBody]
+      .query(HttpCodec.query[String]("query").optional)
+      .out[SimpleOutputBody]
+      .outError[NotFoundError](Status.NotFound)
+
   private val queryParamCollectionEndpoint =
     Endpoint(GET / "withQuery")
       .in[SimpleInputBody]
@@ -194,6 +201,19 @@ object OpenAPIGenSpec extends ZIOSpecDefault {
       .out[SimpleOutputBody]
       .outError[NotFoundError](Status.NotFound)
 
+  private val optionalHeaderEndpoint =
+    Endpoint(GET / "withHeader")
+      .in[SimpleInputBody]
+      .header(HttpCodec.contentType.optional)
+      .out[SimpleOutputBody]
+      .outError[NotFoundError](Status.NotFound)
+
+  private val optionalPayloadEndpoint =
+    Endpoint(GET / "withPayload")
+      .inCodec(HttpCodec.content[Payload].optional)
+      .out[SimpleOutputBody]
+      .outError[NotFoundError](Status.NotFound)
+
   private val alternativeInputEndpoint =
     Endpoint(GET / "inputAlternative")
       .inCodec(
@@ -211,8 +231,31 @@ object OpenAPIGenSpec extends ZIOSpecDefault {
 
   override def spec: Spec[TestEnvironment with Scope, Any] =
     suite("OpenAPIGenSpec")(
+      test("root endpoint to OpenAPI") {
+        val rootEndpoint = Endpoint(Method.GET / empty)
+        val generated    = OpenAPIGen.fromEndpoints("Root Endpoint", "1.0", rootEndpoint)
+        val json         = toJsonAst(generated)
+        val expectedJson = """|{
+                              |  "openapi" : "3.1.0",
+                              |  "info" : {
+                              |    "title" : "Root Endpoint",
+                              |    "version" : "1.0"
+                              |  },
+                              |  "paths" : {
+                              |    "/" : {
+                              |      "get" : {}
+                              |    }
+                              |  },
+                              |  "components" : {}
+                              |}""".stripMargin
+        assertTrue(json == toJsonAst(expectedJson))
+      },
       test("simple endpoint to OpenAPI") {
-        val generated    = OpenAPIGen.fromEndpoints("Simple Endpoint", "1.0", simpleEndpoint.tag("simple", "endpoint"))
+        val generated    = OpenAPIGen.fromEndpoints(
+          "Simple Endpoint",
+          "1.0",
+          simpleEndpoint.tag("simple", "endpoint") ?? Doc.p("some extra doc"),
+        )
         val json         = toJsonAst(generated)
         val expectedJson = """{
                              |  "openapi" : "3.1.0",
@@ -222,7 +265,7 @@ object OpenAPIGenSpec extends ZIOSpecDefault {
                              |  },
                              |  "paths" : {
                              |    "/static/{id}/{uuid}/{name}" : {
-                             |      "description" : "- simple\n- endpoint\n",
+                             |      "description" : "some extra doc\n\n- simple\n- endpoint\n",
                              |      "get" : {
                              |        "tags" : [
                              |          "simple",
@@ -474,6 +517,134 @@ object OpenAPIGenSpec extends ZIOSpecDefault {
                              |}""".stripMargin
         assertTrue(json == toJsonAst(expectedJson))
       },
+      test("with optional query parameter") {
+        val generated    = OpenAPIGen.fromEndpoints("Simple Endpoint", "1.0", queryParamOptEndpoint)
+        val json         = toJsonAst(generated)
+        val expectedJson = """{
+                             |  "openapi" : "3.1.0",
+                             |  "info" : {
+                             |    "title" : "Simple Endpoint",
+                             |    "version" : "1.0"
+                             |  },
+                             |  "paths" : {
+                             |    "/withQuery" : {
+                             |      "get" : {
+                             |        "parameters" : [
+                             |
+                             |            {
+                             |            "name" : "query",
+                             |            "in" : "query",
+                             |            "schema" :
+                             |              {
+                             |              "type" :[
+                             |                "string",
+                             |                "null"
+                             |                ]
+                             |            },
+                             |            "allowReserved" : false,
+                             |            "style" : "form"
+                             |          }
+                             |        ],
+                             |        "requestBody" :
+                             |          {
+                             |          "content" : {
+                             |            "application/json" : {
+                             |              "schema" :
+                             |                {
+                             |                "$ref" : "#/components/schemas/SimpleInputBody"
+                             |              }
+                             |            }
+                             |          },
+                             |          "required" : true
+                             |        },
+                             |        "responses" : {
+                             |          "200" :
+                             |            {
+                             |            "content" : {
+                             |              "application/json" : {
+                             |                "schema" :
+                             |                  {
+                             |                  "$ref" : "#/components/schemas/SimpleOutputBody"
+                             |                }
+                             |              }
+                             |            }
+                             |          },
+                             |          "404" :
+                             |            {
+                             |            "content" : {
+                             |              "application/json" : {
+                             |                "schema" :
+                             |                  {
+                             |                  "$ref" : "#/components/schemas/NotFoundError"
+                             |                }
+                             |              }
+                             |            }
+                             |          }
+                             |        }
+                             |      }
+                             |    }
+                             |  },
+                             |  "components" : {
+                             |    "schemas" : {
+                             |      "NotFoundError" :
+                             |        {
+                             |        "type" :
+                             |          "object",
+                             |        "properties" : {
+                             |          "message" : {
+                             |            "type" :
+                             |              "string"
+                             |          }
+                             |        },
+                             |        "required" : [
+                             |          "message"
+                             |        ]
+                             |      },
+                             |      "SimpleInputBody" :
+                             |        {
+                             |        "type" :
+                             |          "object",
+                             |        "properties" : {
+                             |          "name" : {
+                             |            "type" :
+                             |              "string"
+                             |          },
+                             |          "age" : {
+                             |            "type" :
+                             |              "integer",
+                             |            "format" : "int32"
+                             |          }
+                             |        },
+                             |        "required" : [
+                             |          "name",
+                             |          "age"
+                             |        ]
+                             |      },
+                             |      "SimpleOutputBody" :
+                             |        {
+                             |        "type" :
+                             |          "object",
+                             |        "properties" : {
+                             |          "userName" : {
+                             |            "type" :
+                             |              "string"
+                             |          },
+                             |          "score" : {
+                             |            "type" :
+                             |              "integer",
+                             |            "format" : "int32"
+                             |          }
+                             |        },
+                             |        "required" : [
+                             |          "userName",
+                             |          "score"
+                             |        ]
+                             |      }
+                             |    }
+                             |  }
+                             |}""".stripMargin
+        assertTrue(json == toJsonAst(expectedJson))
+      },
       test("with query parameter with multiple values") {
         val generated    = OpenAPIGen.fromEndpoints("Simple Endpoint", "1.0", queryParamCollectionEndpoint)
         val json         = toJsonAst(generated)
@@ -730,6 +901,213 @@ object OpenAPIGenSpec extends ZIOSpecDefault {
                              |}""".stripMargin
         assertTrue(json == toJsonAst(expectedJson))
       },
+      test("optional header") {
+        val generated    = OpenAPIGen.fromEndpoints("Simple Endpoint", "1.0", optionalHeaderEndpoint)
+        val json         = toJsonAst(generated)
+        val expectedJson = """{
+                             |  "openapi" : "3.1.0",
+                             |  "info" : {
+                             |    "title" : "Simple Endpoint",
+                             |    "version" : "1.0"
+                             |  },
+                             |  "paths" : {
+                             |    "/withHeader" : {
+                             |      "get" : {
+                             |        "parameters" : [
+                             |          {
+                             |            "name" : "content-type",
+                             |            "in" : "header",
+                             |            "schema" : {
+                             |              "type" : [
+                             |                "string",
+                             |                "null"
+                             |              ]
+                             |            },
+                             |            "style" : "simple"
+                             |          }
+                             |        ],
+                             |        "requestBody" : {
+                             |          "content" : {
+                             |            "application/json" : {
+                             |              "schema" : {
+                             |                "$ref" : "#/components/schemas/SimpleInputBody",
+                             |                "description" : ""
+                             |              }
+                             |            }
+                             |          },
+                             |          "required" : true
+                             |        },
+                             |        "responses" : {
+                             |          "200" : {
+                             |            "content" : {
+                             |              "application/json" : {
+                             |                "schema" : {
+                             |                  "$ref" : "#/components/schemas/SimpleOutputBody"
+                             |                }
+                             |              }
+                             |            }
+                             |          },
+                             |          "404" : {
+                             |            "content" : {
+                             |              "application/json" : {
+                             |                "schema" : {
+                             |                  "$ref" : "#/components/schemas/NotFoundError"
+                             |                }
+                             |              }
+                             |            }
+                             |          }
+                             |        }
+                             |      }
+                             |    }
+                             |  },
+                             |  "components" : {
+                             |    "schemas" : {
+                             |      "NotFoundError" : {
+                             |        "type" : "object",
+                             |        "properties" : {
+                             |          "message" : {
+                             |            "type" : "string"
+                             |          }
+                             |        },
+                             |        "required" : [
+                             |          "message"
+                             |        ]
+                             |      },
+                             |      "SimpleInputBody" : {
+                             |        "type" : "object",
+                             |        "properties" : {
+                             |          "name" : {
+                             |            "type" : "string"
+                             |          },
+                             |          "age" : {
+                             |            "type" : "integer",
+                             |            "format" : "int32"
+                             |          }
+                             |        },
+                             |        "required" : [
+                             |          "name",
+                             |          "age"
+                             |        ]
+                             |      },
+                             |      "SimpleOutputBody" : {
+                             |        "type" : "object",
+                             |        "properties" : {
+                             |          "userName" : {
+                             |            "type" : "string"
+                             |          },
+                             |          "score" : {
+                             |            "type" : "integer",
+                             |            "format" : "int32"
+                             |          }
+                             |        },
+                             |        "required" : [
+                             |          "userName",
+                             |          "score"
+                             |        ]
+                             |      }
+                             |    }
+                             |  }
+                             |}""".stripMargin
+        assertTrue(json == toJsonAst(expectedJson))
+      },
+      test("optional payload") {
+        val generated = OpenAPIGen.fromEndpoints("Simple Endpoint", "1.0", optionalPayloadEndpoint)
+        val json      = toJsonAst(generated)
+        val expected  = """{
+                         |  "openapi" : "3.1.0",
+                         |  "info" : {
+                         |    "title" : "Simple Endpoint",
+                         |    "version" : "1.0"
+                         |  },
+                         |  "paths" : {
+                         |    "/withPayload" : {
+                         |      "get" : {
+                         |        "requestBody" : {
+                         |          "content" : {
+                         |            "application/json" : {
+                         |              "schema" : {
+                         |                "anyOf" : [
+                         |                  {
+                         |                    "type" : "null"
+                         |                  },
+                         |                  {
+                         |                    "$ref" : "#/components/schemas/Payload"
+                         |                  }
+                         |                ]
+                         |              }
+                         |            }
+                         |          },
+                         |          "required" : false
+                         |        },
+                         |        "responses" : {
+                         |          "200" : {
+                         |            "content" : {
+                         |              "application/json" : {
+                         |                "schema" : {
+                         |                  "$ref" : "#/components/schemas/SimpleOutputBody"
+                         |                }
+                         |              }
+                         |            }
+                         |          },
+                         |          "404" : {
+                         |            "content" : {
+                         |              "application/json" : {
+                         |                "schema" : {
+                         |                  "$ref" : "#/components/schemas/NotFoundError"
+                         |                }
+                         |              }
+                         |            }
+                         |          }
+                         |        }
+                         |      }
+                         |    }
+                         |  },
+                         |  "components" : {
+                         |    "schemas" : {
+                         |      "NotFoundError" : {
+                         |        "type" : "object",
+                         |        "properties" : {
+                         |          "message" : {
+                         |            "type" : "string"
+                         |          }
+                         |        },
+                         |        "required" : [
+                         |          "message"
+                         |        ]
+                         |      },
+                         |      "Payload" : {
+                         |        "type" : "object",
+                         |        "properties" : {
+                         |          "content" : {
+                         |            "type" : "string"
+                         |          }
+                         |        },
+                         |        "required" : [
+                         |          "content"
+                         |        ],
+                         |        "description" : "A simple payload"
+                         |      },
+                         |      "SimpleOutputBody" : {
+                         |        "type" : "object",
+                         |        "properties" : {
+                         |          "userName" : {
+                         |            "type" : "string"
+                         |          },
+                         |          "score" : {
+                         |            "type" : "integer",
+                         |            "format" : "int32"
+                         |          }
+                         |        },
+                         |        "required" : [
+                         |          "userName",
+                         |          "score"
+                         |        ]
+                         |      }
+                         |    }
+                         |  }
+                         |}""".stripMargin
+        assertTrue(json == toJsonAst(expected))
+      },
       test("alternative input") {
         val generated    = OpenAPIGen.fromEndpoints("Simple Endpoint", "1.0", alternativeInputEndpoint)
         val json         = toJsonAst(generated)
@@ -1379,8 +1757,7 @@ object OpenAPIGenSpec extends ZIOSpecDefault {
                          |                    "width",
                          |                    "height",
                          |                    "metadata"
-                         |                  ],
-                         |                  "description" : "Test doc\n\n"
+                         |                  ]
                          |                }
                          |              }
                          |            }
diff --git a/zio-http/jvm/src/test/scala/zio/http/headers/ForwardedSpec.scala b/zio-http/jvm/src/test/scala/zio/http/headers/ForwardedSpec.scala
index c979b79095..61726d5459 100644
--- a/zio-http/jvm/src/test/scala/zio/http/headers/ForwardedSpec.scala
+++ b/zio-http/jvm/src/test/scala/zio/http/headers/ForwardedSpec.scala
@@ -19,7 +19,7 @@ package zio.http.headers
 import zio.Scope
 import zio.test._
 
-import zio.http.{Header, ZIOHttpSpec}
+import zio.http.{Header, Headers, Request, ZIOHttpSpec}
 
 object ForwardedSpec extends ZIOHttpSpec {
   override def spec: Spec[TestEnvironment with Scope, Any] = suite("Forwarded suite")(
@@ -58,5 +58,22 @@ object ForwardedSpec extends ZIOHttpSpec {
       )
       assertTrue(Header.Forwarded.parse(headerValue) == Right(header))
     },
+    test("render Forwarded produces a valid raw header value") {
+      val gen = for {
+        by    <- Gen.option(Gen.const("by.host"))
+        forv  <- Gen.listOf(
+          Gen.elements("127.0.0.1", "localhost", "0.0.0.0"),
+        )
+        host  <- Gen.option(Gen.const("host.com"))
+        proto <- Gen.option(Gen.const("http"))
+      } yield (by, forv, host, proto)
+
+      check(gen) { case (by, forv, host, proto) =>
+        val expected = Header.Forwarded(by = by, forValues = forv, host = host, proto = proto)
+        val raw      = Header.Forwarded.render(expected)
+        val actual   = Header.Forwarded.parse(raw)
+        assertTrue(actual.is(_.right) == expected).label(s"Rendering result > '${raw}'")
+      }
+    } @@ TestAspect.shrinks(0),
   )
 }
diff --git a/zio-http/jvm/src/test/scala/zio/http/security/SizeLimitsSpec.scala b/zio-http/jvm/src/test/scala/zio/http/security/SizeLimitsSpec.scala
index 2926182a08..8e950a5692 100644
--- a/zio-http/jvm/src/test/scala/zio/http/security/SizeLimitsSpec.scala
+++ b/zio-http/jvm/src/test/scala/zio/http/security/SizeLimitsSpec.scala
@@ -35,6 +35,7 @@ object SizeLimitsSpec extends ZIOHttpSpec {
   val DEFAULT_URL_SIZE     = 4096
   val DEFAULT_HEADER_SIZE  = 8192
   val DEFAULT_CONTENT_SIZE = 1024 * 100
+  val ERROR_MARGIN         = 3
 
   /*
     Checks that for `A` with size until `maxSize`, server responds with `Status.Ok` and `badStatus` after it.
@@ -63,7 +64,7 @@ object SizeLimitsSpec extends ZIOHttpSpec {
         }
         info   <-
           if (expected == status) loop(size + 1, lstTestSize, inc(size)(content), f, expected)
-          else if (size >= lstTestSize - 2) // adding margin for differences in scala 2 and scala 3
+          else if (size >= lstTestSize - ERROR_MARGIN) // adding margin for differences in scala 2 and scala 3
             ZIO.succeed(((size, expected), Some(content)))
           else ZIO.succeed(((size, status), None))
       } yield info
@@ -81,7 +82,7 @@ object SizeLimitsSpec extends ZIOHttpSpec {
       (lstWorkingSize1, lstStatus1) = info1
       (lstWorkingSize2, lstStatus2) = info2
     } yield assertTrue(
-      maxSize - lstWorkingSize1 <= 2,
+      maxSize - lstWorkingSize1 <= ERROR_MARGIN,
       maxSize - lstWorkingSize1 >= 0,
       lstStatus1 == Status.Ok,
       lstWorkingSize2 == lstTestSize,
diff --git a/zio-http/shared/src/main/scala/zio/http/ClientSSLConfig.scala b/zio-http/shared/src/main/scala/zio/http/ClientSSLConfig.scala
index caed30430d..a7a4ab8f7f 100644
--- a/zio-http/shared/src/main/scala/zio/http/ClientSSLConfig.scala
+++ b/zio-http/shared/src/main/scala/zio/http/ClientSSLConfig.scala
@@ -28,6 +28,15 @@ object ClientSSLConfig {
     val trustStorePath     = Config.string("trust-store-path")
     val trustStorePassword = Config.secret("trust-store-password")
 
+    val keyManagerKeyStoreType   = Config.string("keyManagerKeyStoreType")
+    val keyManagerFile           = Config.string("keyManagerFile")
+    val keyManagerResource       = Config.string("keyManagerResource")
+    val keyManagerPassword       = Config.secret("keyManagerPassword")
+    val trustManagerKeyStoreType = Config.string("trustManagerKeyStoreType")
+    val trustManagerFile         = Config.string("trustManagerFile")
+    val trustManagerResource     = Config.string("trustManagerResource")
+    val trustManagerPassword     = Config.secret("trustManagerPassword")
+
     val default                 = Config.succeed(Default)
     val fromCertFile            = certPath.map(FromCertFile(_))
     val fromCertResource        = certPath.map(FromCertResource(_))
@@ -39,6 +48,45 @@ object ClientSSLConfig {
       serverCertConfig.zipWith(clientCertConfig)(FromClientAndServerCert(_, _))
     }
 
+    val fromJavaxNetSsl = {
+      keyManagerKeyStoreType.optional
+        .zip(keyManagerFile.optional)
+        .zip(keyManagerResource.optional)
+        .zip(keyManagerPassword.optional)
+        .zip(trustManagerKeyStoreType.optional)
+        .zip(
+          trustManagerFile.optional
+            .zip(trustManagerResource.optional)
+            .validate("must supply trustManagerFile or trustManagerResource")(pair =>
+              pair._1.isDefined || pair._2.isDefined,
+            ),
+        )
+        .zip(trustManagerPassword.optional)
+        .map { case (kmkst, kmf, kmr, kmpass, tmkst, (tmf, tmr), tmpass) =>
+          val bldr0 =
+            List[(Option[String], FromJavaxNetSsl => String => FromJavaxNetSsl)](
+              (kmkst, b => b.keyManagerKeyStoreType(_)),
+              (kmf, b => b.keyManagerFile),
+              (kmr, b => b.keyManagerResource),
+              (tmkst, b => b.trustManagerKeyStoreType(_)),
+              (tmf, b => b.trustManagerFile),
+              (tmr, b => b.trustManagerResource),
+            )
+              .foldLeft(FromJavaxNetSsl()) { case (bldr, (maybe, lens)) =>
+                maybe.fold(bldr)(s => lens(bldr)(s))
+              }
+
+          List[(Option[Secret], FromJavaxNetSsl => Secret => FromJavaxNetSsl)](
+            (kmpass, b => b.keyManagerPassword(_)),
+            (tmpass, b => b.trustManagerPassword(_)),
+          )
+            .foldLeft(bldr0) { case (bldr, (maybe, lens)) =>
+              maybe.fold(bldr)(s => lens(bldr)(s))
+            }
+            .build()
+        }
+    }
+
     tpe.switch(
       "Default"                 -> default,
       "FromCertFile"            -> fromCertFile,
@@ -58,6 +106,55 @@ object ClientSSLConfig {
     clientCertConfig: ClientSSLCertConfig,
   ) extends ClientSSLConfig
 
+  final case class FromJavaxNetSsl(
+    keyManagerKeyStoreType: String = "JKS",
+    keyManagerSource: FromJavaxNetSsl.Source = FromJavaxNetSsl.Empty,
+    keyManagerPassword: Option[Secret] = None,
+    trustManagerKeyStoreType: String = "JKS",
+    trustManagerSource: FromJavaxNetSsl.Source = FromJavaxNetSsl.Empty,
+    trustManagerPassword: Option[Secret] = None,
+  ) extends ClientSSLConfig { self =>
+
+    def isValidBuild: Boolean    = trustManagerSource != FromJavaxNetSsl.Empty
+    def isInvalidBuild: Boolean  = !isValidBuild
+    def build(): FromJavaxNetSsl = this
+
+    def keyManagerKeyStoreType(tpe: String): FromJavaxNetSsl = self.copy(keyManagerKeyStoreType = tpe)
+    def keyManagerFile(file: String): FromJavaxNetSsl        =
+      keyManagerSource match {
+        case FromJavaxNetSsl.Resource(_) => this
+        case _                           => self.copy(keyManagerSource = FromJavaxNetSsl.File(file))
+      }
+    def keyManagerResource(path: String): FromJavaxNetSsl = self.copy(keyManagerSource = FromJavaxNetSsl.Resource(path))
+    def keyManagerPassword(password: Secret): FromJavaxNetSsl = self.copy(keyManagerPassword = Some(password))
+    def keyManagerPassword(password: String): FromJavaxNetSsl = keyManagerPassword(Secret(password))
+
+    def trustManagerKeyStoreType(tpe: String): FromJavaxNetSsl  = self.copy(trustManagerKeyStoreType = tpe)
+    def trustManagerFile(file: String): FromJavaxNetSsl         =
+      trustManagerSource match {
+        case FromJavaxNetSsl.Resource(_) => this
+        case _                           => self.copy(trustManagerSource = FromJavaxNetSsl.File(file))
+      }
+    def trustManagerResource(path: String): FromJavaxNetSsl     =
+      self.copy(trustManagerSource = FromJavaxNetSsl.Resource(path))
+    def trustManagerPassword(password: Secret): FromJavaxNetSsl = self.copy(trustManagerPassword = Some(password))
+    def trustManagerPassword(password: String): FromJavaxNetSsl = trustManagerPassword(Secret(password))
+  }
+
+  object FromJavaxNetSsl {
+
+    sealed trait Source                         extends Product with Serializable
+    case object Empty                           extends Source
+    final case class File(file: String)         extends Source
+    final case class Resource(resource: String) extends Source
+
+    def builderWithTrustManagerFile(file: String): FromJavaxNetSsl =
+      FromJavaxNetSsl().trustManagerFile(file)
+
+    def builderWithTrustManagerResource(resource: String): FromJavaxNetSsl =
+      FromJavaxNetSsl().trustManagerResource(resource)
+  }
+
   object FromTrustStoreResource {
     def apply(trustStorePath: String, trustStorePassword: String): FromTrustStoreResource =
       FromTrustStoreResource(trustStorePath, Secret(trustStorePassword))
diff --git a/zio-http/shared/src/main/scala/zio/http/ErrorResponseConfig.scala b/zio-http/shared/src/main/scala/zio/http/ErrorResponseConfig.scala
index bc9a3fa8d5..10237403a8 100644
--- a/zio-http/shared/src/main/scala/zio/http/ErrorResponseConfig.scala
+++ b/zio-http/shared/src/main/scala/zio/http/ErrorResponseConfig.scala
@@ -12,6 +12,10 @@ import zio._
  * @param maxStackTraceDepth
  *   maximum number of stack trace lines to include in the response body. Set to
  *   0 to include all lines.
+ * @param errorFormat
+ *   the preferred format for the error response. If the context in which the
+ *   response is created has access to an Accept header, the header will be used
+ *   preferably to determine the format.
  */
 final case class ErrorResponseConfig(
   withErrorBody: Boolean = false,
@@ -38,6 +42,9 @@ object ErrorResponseConfig {
   val debug: HandlerAspect[Any, Unit] =
     Middleware.runBefore(setConfig(debugConfig))
 
+  val debugLayer: ULayer[Unit] =
+    ZLayer(setConfig(debugConfig))
+
   def withConfig(config: ErrorResponseConfig): HandlerAspect[Any, Unit] =
     Middleware.runBefore(setConfig(config))
 
diff --git a/zio-http/shared/src/main/scala/zio/http/Header.scala b/zio-http/shared/src/main/scala/zio/http/Header.scala
index fca8e9d09f..48a87bb8ad 100644
--- a/zio-http/shared/src/main/scala/zio/http/Header.scala
+++ b/zio-http/shared/src/main/scala/zio/http/Header.scala
@@ -2856,8 +2856,14 @@ object Header {
       Right(Forwarded(by, forValue, host, proto))
     }
 
-    def render(forwarded: Forwarded): String =
-      s"${forwarded.by}; ${forwarded.forValues.map(v => s"for=$v").mkString(",")}; ${forwarded.host}; ${forwarded.proto}"
+    def render(forwarded: Forwarded): String = {
+      def formatDirective(directiveName: String, directiveValue: Option[String]) =
+        directiveValue.map(v => s"${directiveName}=${v};").getOrElse("")
+
+      val forValues = if (forwarded.forValues.nonEmpty) forwarded.forValues.mkString("for=", ",for=", ";") else ""
+
+      s"${formatDirective("by", forwarded.by)}${forValues}${formatDirective("host", forwarded.host)}${formatDirective("proto", forwarded.proto)}"
+    }
   }
 
   /** From header value. */
diff --git a/zio-http/shared/src/main/scala/zio/http/Method.scala b/zio-http/shared/src/main/scala/zio/http/Method.scala
index 0e308c402e..8c80ea934e 100644
--- a/zio-http/shared/src/main/scala/zio/http/Method.scala
+++ b/zio-http/shared/src/main/scala/zio/http/Method.scala
@@ -31,7 +31,9 @@ sealed trait Method { self =>
     if (that == Method.ANY) self
     else that
 
-  def /[A](that: PathCodec[A]): RoutePattern[A] = RoutePattern.fromMethod(self) / that
+  def /[A](that: PathCodec[A]): RoutePattern[A] =
+    if (that == PathCodec.empty) RoutePattern.fromMethod(self).asInstanceOf[RoutePattern[A]]
+    else RoutePattern.fromMethod(self) / that
 
   def matches(that: Method): Boolean =
     if (self == Method.ANY) true
diff --git a/zio-http/shared/src/main/scala/zio/http/Route.scala b/zio-http/shared/src/main/scala/zio/http/Route.scala
index 9db2d28d13..617a0f3586 100644
--- a/zio-http/shared/src/main/scala/zio/http/Route.scala
+++ b/zio-http/shared/src/main/scala/zio/http/Route.scala
@@ -49,10 +49,21 @@ sealed trait Route[-Env, +Err] { self =>
    * Handles all typed errors in the route by converting them into responses.
    * This method can be used to convert a route that does not handle its errors
    * into one that does handle its errors.
+   *
+   * If the underlying handler uses the error channel to send responses, this
+   * method will not pass the responses to the provided function.
    */
   final def handleError(f: Err => Response)(implicit trace: Trace): Route[Env, Nothing] =
     self.handleErrorCauseZIO(c => ErrorResponseConfig.configRef.get.map(Response.fromCauseWith(c, _)(f)))
 
+  /**
+   * Handles all typed errors in the route by converting them into a zio effect
+   * that produces a response. This method can be used to convert a route that
+   * does not handle its errors into one that does handle its errors.
+   *
+   * If the underlying handler uses the error channel to send responses, this
+   * method will not pass the responses to the provided function.
+   */
   final def handleErrorZIO[Env1 <: Env](
     f: Err => ZIO[Env1, Nothing, Response],
   )(implicit trace: Trace): Route[Env1, Nothing] =
@@ -67,13 +78,16 @@ sealed trait Route[-Env, +Err] { self =>
    * Handles all typed errors, as well as all non-recoverable errors, by
    * converting them into responses. This method can be used to convert a route
    * that does not handle its errors into one that does handle its errors.
+   *
+   * If the underlying handler uses the error channel to send responses, this
+   * method will not pass the responses to the provided function.
    */
   final def handleErrorCause(f: Cause[Err] => Response)(implicit trace: Trace): Route[Env, Nothing] =
     self match {
       case Provided(route, env)                     => Provided(route.handleErrorCause(f), env)
       case Augmented(route, aspect)                 => Augmented(route.handleErrorCause(f), aspect)
       case Handled(routePattern, handler, location) =>
-        Handled(routePattern, handler.map(_.mapErrorCause(c => f(c.asInstanceOf[Cause[Nothing]]))), location)
+        Handled(routePattern, handler.map(_.mapErrorCause(_.failureOrCause.fold(identity, f))), location)
 
       case Unhandled(pattern, handler0, zippable, location) =>
         val handler2: Handler[Any, Nothing, RoutePattern[_], Handler[Env, Response, Request, Response]] =
@@ -89,7 +103,6 @@ sealed trait Route[-Env, +Err] { self =>
                 }
               }
 
-            // Sandbox before applying aspect:
             paramHandler.mapErrorCause(f)
           }
 
@@ -101,6 +114,9 @@ sealed trait Route[-Env, +Err] { self =>
    * converting them into a ZIO effect that produces the response. This method
    * can be used to convert a route that does not handle its errors into one
    * that does handle its errors.
+   *
+   * If the underlying handler uses the error channel to send responses, this
+   * method will not pass the responses to the provided function.
    */
   final def handleErrorCauseZIO[Env1 <: Env](
     f: Cause[Err] => ZIO[Env1, Nothing, Response],
@@ -120,7 +136,7 @@ sealed trait Route[-Env, +Err] { self =>
       case Augmented(route, aspect)                 =>
         Augmented(route.handleErrorCauseZIO(f).asInstanceOf[Route[Any, Nothing]], aspect)
       case Handled(routePattern, handler, location) =>
-        Handled(routePattern, handler.map(_.mapErrorCauseZIO(c => f(c.asInstanceOf[Cause[Nothing]]))), location)
+        Handled(routePattern, handler.map(_.mapErrorCauseZIO(_.failureOrCause.fold(ZIO.succeed(_), f))), location)
 
       case Unhandled(pattern, handler0, zippable, location) =>
         val handler2: Handler[Any, Nothing, RoutePattern[_], Handler[Env1, Response, Request, Response]] = {
@@ -174,6 +190,9 @@ sealed trait Route[-Env, +Err] { self =>
    * taking into account the request that caused the error. This method can be
    * used to convert a route that does not handle its errors into one that does
    * handle its errors.
+   *
+   * If the underlying handler uses the error channel to send responses, this
+   * method will not pass the responses to the provided function.
    */
   final def handleErrorRequest(f: (Err, Request) => Response)(implicit trace: Trace): Route[Env, Nothing] =
     self.handleErrorRequestCauseZIO((request, cause) =>
@@ -185,6 +204,9 @@ sealed trait Route[-Env, +Err] { self =>
    * converting them into responses, taking into account the request that caused
    * the error. This method can be used to convert a route that does not handle
    * its errors into one that does handle its errors.
+   *
+   * If the underlying handler uses the error channel to send responses, this
+   * method will not pass the responses to the provided function.
    */
   final def handleErrorRequestCause(f: (Request, Cause[Err]) => Response)(implicit trace: Trace): Route[Env, Nothing] =
     self match {
@@ -195,7 +217,7 @@ sealed trait Route[-Env, +Err] { self =>
           routePattern,
           handler0.map { h =>
             Handler.fromFunctionHandler { (req: Request) =>
-              h.mapErrorCause(c => f(req, c.asInstanceOf[Cause[Nothing]]))
+              h.mapErrorCause(_.failureOrCause.fold(identity, f(req, _)))
             }
           },
           location,
@@ -229,6 +251,9 @@ sealed trait Route[-Env, +Err] { self =>
    * account the request that caused the error. This method can be used to
    * convert a route that does not handle its errors into one that does handle
    * its errors.
+   *
+   * If the underlying handler uses the error channel to send responses, this
+   * method will not pass the responses to the provided function.
    */
   final def handleErrorRequestCauseZIO[Env1 <: Env](
     f: (Request, Cause[Err]) => ZIO[Env1, Nothing, Response],
@@ -252,7 +277,7 @@ sealed trait Route[-Env, +Err] { self =>
           routePattern,
           handler.map { handler =>
             Handler.fromFunctionHandler { (req: Request) =>
-              handler.mapErrorCauseZIO(c => f(req, c.asInstanceOf[Cause[Nothing]]))
+              handler.mapErrorCauseZIO(_.failureOrCause.fold(ZIO.succeed(_), f(req, _)))
             }
           },
           location,
@@ -336,10 +361,8 @@ object Route                   {
 
   def handledIgnoreParams[Env](
     routePattern: RoutePattern[_],
-  )(handler0: Handler[Env, Response, Request, Response])(implicit trace: Trace): Route[Env, Nothing] = {
-    // Sandbox before constructing:
-    Route.Handled(routePattern, handler((_: RoutePattern[_]) => handler0.sandbox), Trace.empty)
-  }
+  )(handler0: Handler[Env, Response, Request, Response])(implicit trace: Trace): Route[Env, Nothing] =
+    Route.Handled(routePattern, handler((_: RoutePattern[_]) => handler0), Trace.empty)
 
   def handled[Params, Env](rpm: RoutePattern[Params]): HandledConstructor[Env, Params] =
     new HandledConstructor[Env, Params](rpm)
@@ -365,7 +388,7 @@ object Route                   {
             }
 
           // Sandbox before applying aspect:
-          paramHandler.sandbox
+          paramHandler
         }
       }
 
@@ -414,7 +437,7 @@ object Route                   {
     location: Trace,
   ) extends Route[Env, Nothing] {
     override def toHandler(implicit ev: Nothing <:< Response, trace: Trace): Handler[Env, Response, Request, Response] =
-      Handler.fromZIO(handler(routePattern)).flatten
+      Handler.fromZIO(handler(routePattern).map(_.sandbox)).flatten
 
     override def toString = s"Route.Handled(${routePattern}, ${location})"
   }
diff --git a/zio-http/shared/src/main/scala/zio/http/RoutePattern.scala b/zio-http/shared/src/main/scala/zio/http/RoutePattern.scala
index 52c475f16d..7bcdff3505 100644
--- a/zio-http/shared/src/main/scala/zio/http/RoutePattern.scala
+++ b/zio-http/shared/src/main/scala/zio/http/RoutePattern.scala
@@ -53,7 +53,9 @@ final case class RoutePattern[A](method: Method, pathCodec: PathCodec[A]) { self
    * Returns a new pattern that is extended with the specified segment pattern.
    */
   def /[B](that: PathCodec[B])(implicit combiner: Combiner[A, B]): RoutePattern[combiner.Out] =
-    copy(pathCodec = pathCodec ++ that)
+    if (that == PathCodec.empty) self.asInstanceOf[RoutePattern[combiner.Out]]
+    else if (pathCodec == PathCodec.empty) copy(pathCodec = that.asInstanceOf[PathCodec[combiner.Out]])
+    else copy(pathCodec = pathCodec ++ that)
 
   /**
    * Creates a route from this pattern and the specified handler.
diff --git a/zio-http/shared/src/main/scala/zio/http/codec/Doc.scala b/zio-http/shared/src/main/scala/zio/http/codec/Doc.scala
index f6e7f3d221..e10dbc90ae 100644
--- a/zio-http/shared/src/main/scala/zio/http/codec/Doc.scala
+++ b/zio-http/shared/src/main/scala/zio/http/codec/Doc.scala
@@ -31,9 +31,10 @@ sealed trait Doc { self =>
 
   def +(that: Doc): Doc =
     (self, that) match {
-      case (self, that) if self.isEmpty => that
-      case (self, that) if that.isEmpty => self
-      case _                            => Doc.Sequence(self, that)
+      case (self, that) if self.isEmpty           => that
+      case (self, that) if that.isEmpty           => self
+      case _ if tags.isEmpty && that.tags.isEmpty => Doc.Sequence(self, that)
+      case _                                      => Doc.Sequence(self, that).tag(self.tags ++ that.tags)
     }
 
   def isEmpty: Boolean =
@@ -148,7 +149,8 @@ sealed trait Doc { self =>
         case Doc.Raw(_, docType) =>
           throw new IllegalArgumentException(s"Unsupported raw doc type: $docType")
 
-        case Doc.Tagged(_, _) =>
+        case Doc.Tagged(doc, _) =>
+          render(doc, indent)
 
       }
     }
diff --git a/zio-http/shared/src/main/scala/zio/http/codec/HttpCodec.scala b/zio-http/shared/src/main/scala/zio/http/codec/HttpCodec.scala
index df546bd0da..278f185366 100644
--- a/zio-http/shared/src/main/scala/zio/http/codec/HttpCodec.scala
+++ b/zio-http/shared/src/main/scala/zio/http/codec/HttpCodec.scala
@@ -530,6 +530,1680 @@ object HttpCodec extends ContentCodecs with HeaderCodecs with MethodCodecs with
           case _          => Left(s"Unexpected error type")
         },
       )
+
+    def f9[
+      AtomTypes,
+      Sub1 <: Value: ClassTag,
+      Sub2 <: Value: ClassTag,
+      Sub3 <: Value: ClassTag,
+      Sub4 <: Value: ClassTag,
+      Sub5 <: Value: ClassTag,
+      Sub6 <: Value: ClassTag,
+      Sub7 <: Value: ClassTag,
+      Sub8 <: Value: ClassTag,
+      Sub9 <: Value: ClassTag,
+    ](
+      codec1: HttpCodec[AtomTypes, Sub1],
+      codec2: HttpCodec[AtomTypes, Sub2],
+      codec3: HttpCodec[AtomTypes, Sub3],
+      codec4: HttpCodec[AtomTypes, Sub4],
+      codec5: HttpCodec[AtomTypes, Sub5],
+      codec6: HttpCodec[AtomTypes, Sub6],
+      codec7: HttpCodec[AtomTypes, Sub7],
+      codec8: HttpCodec[AtomTypes, Sub8],
+      codec9: HttpCodec[AtomTypes, Sub9],
+    ): HttpCodec[AtomTypes, Value] =
+      (codec1 | codec2 | codec3 | codec4 | codec5 | codec6 | codec7 | codec8 | codec9).transformOrFail(either =>
+        Right(
+          either.left
+            .map(
+              _.left
+                .map(_.left.map(_.left.map(_.left.map(_.left.map(_.left.map(_.merge).merge).merge).merge).merge).merge)
+                .merge,
+            )
+            .merge,
+        ),
+      )((value: Value) =>
+        value match {
+          case sub1: Sub1 => Right(Left(Left(Left(Left(Left(Left(Left(Left(sub1)))))))))
+          case sub2: Sub2 => Right(Left(Left(Left(Left(Left(Left(Left(Right(sub2)))))))))
+          case sub3: Sub3 => Right(Left(Left(Left(Left(Left(Left(Right(sub3))))))))
+          case sub4: Sub4 => Right(Left(Left(Left(Left(Left(Right(sub4)))))))
+          case sub5: Sub5 => Right(Left(Left(Left(Left(Right(sub5))))))
+          case sub6: Sub6 => Right(Left(Left(Left(Right(sub6)))))
+          case sub7: Sub7 => Right(Left(Left(Right(sub7))))
+          case sub8: Sub8 => Right(Left(Right(sub8)))
+          case sub9: Sub9 => Right(Right(sub9))
+          case _          => Left(s"Unexpected error type")
+        },
+      )
+
+    def f10[
+      AtomTypes,
+      Sub1 <: Value: ClassTag,
+      Sub2 <: Value: ClassTag,
+      Sub3 <: Value: ClassTag,
+      Sub4 <: Value: ClassTag,
+      Sub5 <: Value: ClassTag,
+      Sub6 <: Value: ClassTag,
+      Sub7 <: Value: ClassTag,
+      Sub8 <: Value: ClassTag,
+      Sub9 <: Value: ClassTag,
+      Sub10 <: Value: ClassTag,
+    ](
+      codec1: HttpCodec[AtomTypes, Sub1],
+      codec2: HttpCodec[AtomTypes, Sub2],
+      codec3: HttpCodec[AtomTypes, Sub3],
+      codec4: HttpCodec[AtomTypes, Sub4],
+      codec5: HttpCodec[AtomTypes, Sub5],
+      codec6: HttpCodec[AtomTypes, Sub6],
+      codec7: HttpCodec[AtomTypes, Sub7],
+      codec8: HttpCodec[AtomTypes, Sub8],
+      codec9: HttpCodec[AtomTypes, Sub9],
+      codec10: HttpCodec[AtomTypes, Sub10],
+    ): HttpCodec[AtomTypes, Value] =
+      (codec1 | codec2 | codec3 | codec4 | codec5 | codec6 | codec7 | codec8 | codec9 | codec10).transformOrFail(
+        either =>
+          Right(
+            either.left
+              .map(
+                _.left
+                  .map(
+                    _.left
+                      .map(
+                        _.left
+                          .map(_.left.map(_.left.map(_.left.map(_.left.map(_.merge).merge).merge).merge).merge)
+                          .merge,
+                      )
+                      .merge,
+                  )
+                  .merge,
+              )
+              .merge,
+          ),
+      )((value: Value) =>
+        value match {
+          case sub1: Sub1   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(sub1))))))))))
+          case sub2: Sub2   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub2))))))))))
+          case sub3: Sub3   => Right(Left(Left(Left(Left(Left(Left(Left(Right(sub3)))))))))
+          case sub4: Sub4   => Right(Left(Left(Left(Left(Left(Left(Right(sub4))))))))
+          case sub5: Sub5   => Right(Left(Left(Left(Left(Left(Right(sub5)))))))
+          case sub6: Sub6   => Right(Left(Left(Left(Left(Right(sub6))))))
+          case sub7: Sub7   => Right(Left(Left(Left(Right(sub7)))))
+          case sub8: Sub8   => Right(Left(Left(Right(sub8))))
+          case sub9: Sub9   => Right(Left(Right(sub9)))
+          case sub10: Sub10 => Right(Right(sub10))
+          case _            => Left(s"Unexpected error type")
+        },
+      )
+
+    def f11[
+      AtomTypes,
+      Sub1 <: Value: ClassTag,
+      Sub2 <: Value: ClassTag,
+      Sub3 <: Value: ClassTag,
+      Sub4 <: Value: ClassTag,
+      Sub5 <: Value: ClassTag,
+      Sub6 <: Value: ClassTag,
+      Sub7 <: Value: ClassTag,
+      Sub8 <: Value: ClassTag,
+      Sub9 <: Value: ClassTag,
+      Sub10 <: Value: ClassTag,
+      Sub11 <: Value: ClassTag,
+    ](
+      codec1: HttpCodec[AtomTypes, Sub1],
+      codec2: HttpCodec[AtomTypes, Sub2],
+      codec3: HttpCodec[AtomTypes, Sub3],
+      codec4: HttpCodec[AtomTypes, Sub4],
+      codec5: HttpCodec[AtomTypes, Sub5],
+      codec6: HttpCodec[AtomTypes, Sub6],
+      codec7: HttpCodec[AtomTypes, Sub7],
+      codec8: HttpCodec[AtomTypes, Sub8],
+      codec9: HttpCodec[AtomTypes, Sub9],
+      codec10: HttpCodec[AtomTypes, Sub10],
+      codec11: HttpCodec[AtomTypes, Sub11],
+    ): HttpCodec[AtomTypes, Value] =
+      (codec1 | codec2 | codec3 | codec4 | codec5 | codec6 | codec7 | codec8 | codec9 | codec10 | codec11)
+        .transformOrFail(either =>
+          Right(
+            either.left
+              .map(
+                _.left
+                  .map(
+                    _.left
+                      .map(
+                        _.left
+                          .map(
+                            _.left
+                              .map(_.left.map(_.left.map(_.left.map(_.left.map(_.merge).merge).merge).merge).merge)
+                              .merge,
+                          )
+                          .merge,
+                      )
+                      .merge,
+                  )
+                  .merge,
+              )
+              .merge,
+          ),
+        )((value: Value) =>
+          value match {
+            case sub1: Sub1   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(sub1)))))))))))
+            case sub2: Sub2   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub2)))))))))))
+            case sub3: Sub3   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub3))))))))))
+            case sub4: Sub4   => Right(Left(Left(Left(Left(Left(Left(Left(Right(sub4)))))))))
+            case sub5: Sub5   => Right(Left(Left(Left(Left(Left(Left(Right(sub5))))))))
+            case sub6: Sub6   => Right(Left(Left(Left(Left(Left(Right(sub6)))))))
+            case sub7: Sub7   => Right(Left(Left(Left(Left(Right(sub7))))))
+            case sub8: Sub8   => Right(Left(Left(Left(Right(sub8)))))
+            case sub9: Sub9   => Right(Left(Left(Right(sub9))))
+            case sub10: Sub10 => Right(Left(Right(sub10)))
+            case sub11: Sub11 => Right(Right(sub11))
+            case _            => Left(s"Unexpected error type")
+          },
+        )
+    def f12[
+      AtomTypes,
+      Sub1 <: Value: ClassTag,
+      Sub2 <: Value: ClassTag,
+      Sub3 <: Value: ClassTag,
+      Sub4 <: Value: ClassTag,
+      Sub5 <: Value: ClassTag,
+      Sub6 <: Value: ClassTag,
+      Sub7 <: Value: ClassTag,
+      Sub8 <: Value: ClassTag,
+      Sub9 <: Value: ClassTag,
+      Sub10 <: Value: ClassTag,
+      Sub11 <: Value: ClassTag,
+      Sub12 <: Value: ClassTag,
+    ](
+      codec1: HttpCodec[AtomTypes, Sub1],
+      codec2: HttpCodec[AtomTypes, Sub2],
+      codec3: HttpCodec[AtomTypes, Sub3],
+      codec4: HttpCodec[AtomTypes, Sub4],
+      codec5: HttpCodec[AtomTypes, Sub5],
+      codec6: HttpCodec[AtomTypes, Sub6],
+      codec7: HttpCodec[AtomTypes, Sub7],
+      codec8: HttpCodec[AtomTypes, Sub8],
+      codec9: HttpCodec[AtomTypes, Sub9],
+      codec10: HttpCodec[AtomTypes, Sub10],
+      codec11: HttpCodec[AtomTypes, Sub11],
+      codec12: HttpCodec[AtomTypes, Sub12],
+    ): HttpCodec[AtomTypes, Value] =
+      (codec1 | codec2 | codec3 | codec4 | codec5 | codec6 | codec7 | codec8 | codec9 | codec10 | codec11 | codec12)
+        .transformOrFail(either =>
+          Right(
+            either.left
+              .map(
+                _.left
+                  .map(
+                    _.left
+                      .map(
+                        _.left
+                          .map(
+                            _.left
+                              .map(
+                                _.left
+                                  .map(_.left.map(_.left.map(_.left.map(_.left.map(_.merge).merge).merge).merge).merge)
+                                  .merge,
+                              )
+                              .merge,
+                          )
+                          .merge,
+                      )
+                      .merge,
+                  )
+                  .merge,
+              )
+              .merge,
+          ),
+        )((value: Value) =>
+          value match {
+            case sub1: Sub1   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(sub1))))))))))))
+            case sub2: Sub2   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub2))))))))))))
+            case sub3: Sub3   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub3)))))))))))
+            case sub4: Sub4   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub4))))))))))
+            case sub5: Sub5   => Right(Left(Left(Left(Left(Left(Left(Left(Right(sub5)))))))))
+            case sub6: Sub6   => Right(Left(Left(Left(Left(Left(Left(Right(sub6))))))))
+            case sub7: Sub7   => Right(Left(Left(Left(Left(Left(Right(sub7)))))))
+            case sub8: Sub8   => Right(Left(Left(Left(Left(Right(sub8))))))
+            case sub9: Sub9   => Right(Left(Left(Left(Right(sub9)))))
+            case sub10: Sub10 => Right(Left(Left(Right(sub10))))
+            case sub11: Sub11 => Right(Left(Right(sub11)))
+            case sub12: Sub12 => Right(Right(sub12))
+            case _            => Left(s"Unexpected error type")
+          },
+        )
+    def f13[
+      AtomTypes,
+      Sub1 <: Value: ClassTag,
+      Sub2 <: Value: ClassTag,
+      Sub3 <: Value: ClassTag,
+      Sub4 <: Value: ClassTag,
+      Sub5 <: Value: ClassTag,
+      Sub6 <: Value: ClassTag,
+      Sub7 <: Value: ClassTag,
+      Sub8 <: Value: ClassTag,
+      Sub9 <: Value: ClassTag,
+      Sub10 <: Value: ClassTag,
+      Sub11 <: Value: ClassTag,
+      Sub12 <: Value: ClassTag,
+      Sub13 <: Value: ClassTag,
+    ](
+      codec1: HttpCodec[AtomTypes, Sub1],
+      codec2: HttpCodec[AtomTypes, Sub2],
+      codec3: HttpCodec[AtomTypes, Sub3],
+      codec4: HttpCodec[AtomTypes, Sub4],
+      codec5: HttpCodec[AtomTypes, Sub5],
+      codec6: HttpCodec[AtomTypes, Sub6],
+      codec7: HttpCodec[AtomTypes, Sub7],
+      codec8: HttpCodec[AtomTypes, Sub8],
+      codec9: HttpCodec[AtomTypes, Sub9],
+      codec10: HttpCodec[AtomTypes, Sub10],
+      codec11: HttpCodec[AtomTypes, Sub11],
+      codec12: HttpCodec[AtomTypes, Sub12],
+      codec13: HttpCodec[AtomTypes, Sub13],
+    ): HttpCodec[AtomTypes, Value] =
+      (codec1 | codec2 | codec3 | codec4 | codec5 | codec6 | codec7 | codec8 | codec9 | codec10 | codec11 | codec12 | codec13)
+        .transformOrFail(either =>
+          Right(
+            either.left
+              .map(
+                _.left
+                  .map(
+                    _.left
+                      .map(
+                        _.left
+                          .map(
+                            _.left
+                              .map(
+                                _.left
+                                  .map(
+                                    _.left
+                                      .map(
+                                        _.left.map(_.left.map(_.left.map(_.left.map(_.merge).merge).merge).merge).merge,
+                                      )
+                                      .merge,
+                                  )
+                                  .merge,
+                              )
+                              .merge,
+                          )
+                          .merge,
+                      )
+                      .merge,
+                  )
+                  .merge,
+              )
+              .merge,
+          ),
+        )((value: Value) =>
+          value match {
+            case sub1: Sub1   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(sub1)))))))))))))
+            case sub2: Sub2   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub2)))))))))))))
+            case sub3: Sub3   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub3))))))))))))
+            case sub4: Sub4   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub4)))))))))))
+            case sub5: Sub5   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub5))))))))))
+            case sub6: Sub6   => Right(Left(Left(Left(Left(Left(Left(Left(Right(sub6)))))))))
+            case sub7: Sub7   => Right(Left(Left(Left(Left(Left(Left(Right(sub7))))))))
+            case sub8: Sub8   => Right(Left(Left(Left(Left(Left(Right(sub8)))))))
+            case sub9: Sub9   => Right(Left(Left(Left(Left(Right(sub9))))))
+            case sub10: Sub10 => Right(Left(Left(Left(Right(sub10)))))
+            case sub11: Sub11 => Right(Left(Left(Right(sub11))))
+            case sub12: Sub12 => Right(Left(Right(sub12)))
+            case sub13: Sub13 => Right(Right(sub13))
+            case _            => Left(s"Unexpected error type")
+          },
+        )
+    def f14[
+      AtomTypes,
+      Sub1 <: Value: ClassTag,
+      Sub2 <: Value: ClassTag,
+      Sub3 <: Value: ClassTag,
+      Sub4 <: Value: ClassTag,
+      Sub5 <: Value: ClassTag,
+      Sub6 <: Value: ClassTag,
+      Sub7 <: Value: ClassTag,
+      Sub8 <: Value: ClassTag,
+      Sub9 <: Value: ClassTag,
+      Sub10 <: Value: ClassTag,
+      Sub11 <: Value: ClassTag,
+      Sub12 <: Value: ClassTag,
+      Sub13 <: Value: ClassTag,
+      Sub14 <: Value: ClassTag,
+    ](
+      codec1: HttpCodec[AtomTypes, Sub1],
+      codec2: HttpCodec[AtomTypes, Sub2],
+      codec3: HttpCodec[AtomTypes, Sub3],
+      codec4: HttpCodec[AtomTypes, Sub4],
+      codec5: HttpCodec[AtomTypes, Sub5],
+      codec6: HttpCodec[AtomTypes, Sub6],
+      codec7: HttpCodec[AtomTypes, Sub7],
+      codec8: HttpCodec[AtomTypes, Sub8],
+      codec9: HttpCodec[AtomTypes, Sub9],
+      codec10: HttpCodec[AtomTypes, Sub10],
+      codec11: HttpCodec[AtomTypes, Sub11],
+      codec12: HttpCodec[AtomTypes, Sub12],
+      codec13: HttpCodec[AtomTypes, Sub13],
+      codec14: HttpCodec[AtomTypes, Sub14],
+    ): HttpCodec[AtomTypes, Value] =
+      (codec1 | codec2 | codec3 | codec4 | codec5 | codec6 | codec7 | codec8 | codec9 | codec10 | codec11 | codec12 | codec13 | codec14)
+        .transformOrFail(either =>
+          Right(
+            either.left
+              .map(
+                _.left
+                  .map(
+                    _.left
+                      .map(
+                        _.left
+                          .map(
+                            _.left
+                              .map(
+                                _.left
+                                  .map(
+                                    _.left
+                                      .map(
+                                        _.left
+                                          .map(
+                                            _.left
+                                              .map(_.left.map(_.left.map(_.left.map(_.merge).merge).merge).merge)
+                                              .merge,
+                                          )
+                                          .merge,
+                                      )
+                                      .merge,
+                                  )
+                                  .merge,
+                              )
+                              .merge,
+                          )
+                          .merge,
+                      )
+                      .merge,
+                  )
+                  .merge,
+              )
+              .merge,
+          ),
+        )(value =>
+          value match {
+            case sub1: Sub1 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(sub1))))))))))))))
+            case sub2: Sub2 =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub2))))))))))))))
+            case sub3: Sub3 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub3)))))))))))))
+            case sub4: Sub4 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub4))))))))))))
+            case sub5: Sub5 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub5)))))))))))
+            case sub6: Sub6 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub6))))))))))
+            case sub7: Sub7 => Right(Left(Left(Left(Left(Left(Left(Left(Right(sub7)))))))))
+            case sub8: Sub8 => Right(Left(Left(Left(Left(Left(Left(Right(sub8))))))))
+            case sub9: Sub9 => Right(Left(Left(Left(Left(Left(Right(sub9)))))))
+            case sub10: Sub10 => Right(Left(Left(Left(Left(Right(sub10))))))
+            case sub11: Sub11 => Right(Left(Left(Left(Right(sub11)))))
+            case sub12: Sub12 => Right(Left(Left(Right(sub12))))
+            case sub13: Sub13 => Right(Left(Right(sub13)))
+            case sub14: Sub14 => Right(Right(sub14))
+            case _            => Left(s"Unexpected error type")
+          },
+        )
+
+    def f15[
+      AtomTypes,
+      Sub1 <: Value: ClassTag,
+      Sub2 <: Value: ClassTag,
+      Sub3 <: Value: ClassTag,
+      Sub4 <: Value: ClassTag,
+      Sub5 <: Value: ClassTag,
+      Sub6 <: Value: ClassTag,
+      Sub7 <: Value: ClassTag,
+      Sub8 <: Value: ClassTag,
+      Sub9 <: Value: ClassTag,
+      Sub10 <: Value: ClassTag,
+      Sub11 <: Value: ClassTag,
+      Sub12 <: Value: ClassTag,
+      Sub13 <: Value: ClassTag,
+      Sub14 <: Value: ClassTag,
+      Sub15 <: Value: ClassTag,
+    ](
+      codec1: HttpCodec[AtomTypes, Sub1],
+      codec2: HttpCodec[AtomTypes, Sub2],
+      codec3: HttpCodec[AtomTypes, Sub3],
+      codec4: HttpCodec[AtomTypes, Sub4],
+      codec5: HttpCodec[AtomTypes, Sub5],
+      codec6: HttpCodec[AtomTypes, Sub6],
+      codec7: HttpCodec[AtomTypes, Sub7],
+      codec8: HttpCodec[AtomTypes, Sub8],
+      codec9: HttpCodec[AtomTypes, Sub9],
+      codec10: HttpCodec[AtomTypes, Sub10],
+      codec11: HttpCodec[AtomTypes, Sub11],
+      codec12: HttpCodec[AtomTypes, Sub12],
+      codec13: HttpCodec[AtomTypes, Sub13],
+      codec14: HttpCodec[AtomTypes, Sub14],
+      codec15: HttpCodec[AtomTypes, Sub15],
+    ): HttpCodec[AtomTypes, Value] =
+      (codec1 | codec2 | codec3 | codec4 | codec5 | codec6 | codec7 | codec8 | codec9 | codec10 | codec11 | codec12 | codec13 | codec14 | codec15)
+        .transformOrFail(either =>
+          Right(
+            either.left
+              .map(
+                _.left
+                  .map(
+                    _.left
+                      .map(
+                        _.left
+                          .map(
+                            _.left
+                              .map(
+                                _.left
+                                  .map(
+                                    _.left
+                                      .map(
+                                        _.left
+                                          .map(
+                                            _.left
+                                              .map(
+                                                _.left
+                                                  .map(_.left.map(_.left.map(_.left.map(_.merge).merge).merge).merge)
+                                                  .merge,
+                                              )
+                                              .merge,
+                                          )
+                                          .merge,
+                                      )
+                                      .merge,
+                                  )
+                                  .merge,
+                              )
+                              .merge,
+                          )
+                          .merge,
+                      )
+                      .merge,
+                  )
+                  .merge,
+              )
+              .merge,
+          ),
+        )((value: Value) =>
+          value match {
+            case sub1: Sub1   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(sub1)))))))))))))))
+            case sub2: Sub2   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub2)))))))))))))))
+            case sub3: Sub3   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub3))))))))))))))
+            case sub4: Sub4   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub4)))))))))))))
+            case sub5: Sub5   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub5))))))))))))
+            case sub6: Sub6   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub6)))))))))))
+            case sub7: Sub7   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub7))))))))))
+            case sub8: Sub8   => Right(Left(Left(Left(Left(Left(Left(Left(Right(sub8)))))))))
+            case sub9: Sub9   => Right(Left(Left(Left(Left(Left(Left(Right(sub9))))))))
+            case sub10: Sub10 => Right(Left(Left(Left(Left(Left(Right(sub10)))))))
+            case sub11: Sub11 => Right(Left(Left(Left(Left(Right(sub11))))))
+            case sub12: Sub12 => Right(Left(Left(Left(Right(sub12)))))
+            case sub13: Sub13 => Right(Left(Left(Right(sub13))))
+            case sub14: Sub14 => Right(Left(Right(sub14)))
+            case sub15: Sub15 => Right(Right(sub15))
+            case _            => Left(s"Unexpected error type")
+
+          },
+        )
+
+    def f16[
+      AtomTypes,
+      Sub1 <: Value: ClassTag,
+      Sub2 <: Value: ClassTag,
+      Sub3 <: Value: ClassTag,
+      Sub4 <: Value: ClassTag,
+      Sub5 <: Value: ClassTag,
+      Sub6 <: Value: ClassTag,
+      Sub7 <: Value: ClassTag,
+      Sub8 <: Value: ClassTag,
+      Sub9 <: Value: ClassTag,
+      Sub10 <: Value: ClassTag,
+      Sub11 <: Value: ClassTag,
+      Sub12 <: Value: ClassTag,
+      Sub13 <: Value: ClassTag,
+      Sub14 <: Value: ClassTag,
+      Sub15 <: Value: ClassTag,
+      Sub16 <: Value: ClassTag,
+    ](
+      codec1: HttpCodec[AtomTypes, Sub1],
+      codec2: HttpCodec[AtomTypes, Sub2],
+      codec3: HttpCodec[AtomTypes, Sub3],
+      codec4: HttpCodec[AtomTypes, Sub4],
+      codec5: HttpCodec[AtomTypes, Sub5],
+      codec6: HttpCodec[AtomTypes, Sub6],
+      codec7: HttpCodec[AtomTypes, Sub7],
+      codec8: HttpCodec[AtomTypes, Sub8],
+      codec9: HttpCodec[AtomTypes, Sub9],
+      codec10: HttpCodec[AtomTypes, Sub10],
+      codec11: HttpCodec[AtomTypes, Sub11],
+      codec12: HttpCodec[AtomTypes, Sub12],
+      codec13: HttpCodec[AtomTypes, Sub13],
+      codec14: HttpCodec[AtomTypes, Sub14],
+      codec15: HttpCodec[AtomTypes, Sub15],
+      codec16: HttpCodec[AtomTypes, Sub16],
+    ): HttpCodec[AtomTypes, Value] =
+      (codec1 | codec2 | codec3 | codec4 | codec5 | codec6 | codec7 | codec8 | codec9 | codec10 | codec11 | codec12 | codec13 | codec14 | codec15 | codec16)
+        .transformOrFail(either =>
+          Right(
+            either.left
+              .map(
+                _.left
+                  .map(
+                    _.left
+                      .map(
+                        _.left
+                          .map(
+                            _.left
+                              .map(
+                                _.left
+                                  .map(
+                                    _.left
+                                      .map(
+                                        _.left
+                                          .map(
+                                            _.left
+                                              .map(
+                                                _.left
+                                                  .map(
+                                                    _.left
+                                                      .map(
+                                                        _.left.map(_.left.map(_.left.map(_.merge).merge).merge).merge,
+                                                      )
+                                                      .merge,
+                                                  )
+                                                  .merge,
+                                              )
+                                              .merge,
+                                          )
+                                          .merge,
+                                      )
+                                      .merge,
+                                  )
+                                  .merge,
+                              )
+                              .merge,
+                          )
+                          .merge,
+                      )
+                      .merge,
+                  )
+                  .merge,
+              )
+              .merge,
+          ),
+        )((value: Value) =>
+          value match {
+            case sub1: Sub1   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(sub1))))))))))))))))
+            case sub2: Sub2   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub2))))))))))))))))
+            case sub3: Sub3   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub3)))))))))))))))
+            case sub4: Sub4   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub4))))))))))))))
+            case sub5: Sub5   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub5)))))))))))))
+            case sub6: Sub6   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub6))))))))))))
+            case sub7: Sub7   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub7)))))))))))
+            case sub8: Sub8   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub8))))))))))
+            case sub9: Sub9   => Right(Left(Left(Left(Left(Left(Left(Left(Right(sub9)))))))))
+            case sub10: Sub10 => Right(Left(Left(Left(Left(Left(Left(Right(sub10))))))))
+            case sub11: Sub11 => Right(Left(Left(Left(Left(Left(Right(sub11)))))))
+            case sub12: Sub12 => Right(Left(Left(Left(Left(Right(sub12))))))
+            case sub13: Sub13 => Right(Left(Left(Left(Right(sub13)))))
+            case sub14: Sub14 => Right(Left(Left(Right(sub14))))
+            case sub15: Sub15 => Right(Left(Right(sub15)))
+            case sub16: Sub16 => Right(Right(sub16))
+            case _            => Left(s"Unexpected error type")
+          },
+        )
+
+    def f17[
+      AtomTypes,
+      Sub1 <: Value: ClassTag,
+      Sub2 <: Value: ClassTag,
+      Sub3 <: Value: ClassTag,
+      Sub4 <: Value: ClassTag,
+      Sub5 <: Value: ClassTag,
+      Sub6 <: Value: ClassTag,
+      Sub7 <: Value: ClassTag,
+      Sub8 <: Value: ClassTag,
+      Sub9 <: Value: ClassTag,
+      Sub10 <: Value: ClassTag,
+      Sub11 <: Value: ClassTag,
+      Sub12 <: Value: ClassTag,
+      Sub13 <: Value: ClassTag,
+      Sub14 <: Value: ClassTag,
+      Sub15 <: Value: ClassTag,
+      Sub16 <: Value: ClassTag,
+      Sub17 <: Value: ClassTag,
+    ](
+      codec1: HttpCodec[AtomTypes, Sub1],
+      codec2: HttpCodec[AtomTypes, Sub2],
+      codec3: HttpCodec[AtomTypes, Sub3],
+      codec4: HttpCodec[AtomTypes, Sub4],
+      codec5: HttpCodec[AtomTypes, Sub5],
+      codec6: HttpCodec[AtomTypes, Sub6],
+      codec7: HttpCodec[AtomTypes, Sub7],
+      codec8: HttpCodec[AtomTypes, Sub8],
+      codec9: HttpCodec[AtomTypes, Sub9],
+      codec10: HttpCodec[AtomTypes, Sub10],
+      codec11: HttpCodec[AtomTypes, Sub11],
+      codec12: HttpCodec[AtomTypes, Sub12],
+      codec13: HttpCodec[AtomTypes, Sub13],
+      codec14: HttpCodec[AtomTypes, Sub14],
+      codec15: HttpCodec[AtomTypes, Sub15],
+      codec16: HttpCodec[AtomTypes, Sub16],
+      codec17: HttpCodec[AtomTypes, Sub17],
+    ): HttpCodec[AtomTypes, Value] =
+      (codec1 | codec2 | codec3 | codec4 | codec5 | codec6 | codec7 | codec8 | codec9 | codec10 | codec11 | codec12 | codec13 | codec14 | codec15 | codec16 | codec17)
+        .transformOrFail(either =>
+          Right(
+            either.left
+              .map(
+                _.left
+                  .map(
+                    _.left
+                      .map(
+                        _.left
+                          .map(
+                            _.left
+                              .map(
+                                _.left
+                                  .map(
+                                    _.left
+                                      .map(
+                                        _.left
+                                          .map(
+                                            _.left
+                                              .map(
+                                                _.left
+                                                  .map(
+                                                    _.left
+                                                      .map(
+                                                        _.left
+                                                          .map(
+                                                            _.left
+                                                              .map(_.left.map(_.left.map(_.merge).merge).merge)
+                                                              .merge,
+                                                          )
+                                                          .merge,
+                                                      )
+                                                      .merge,
+                                                  )
+                                                  .merge,
+                                              )
+                                              .merge,
+                                          )
+                                          .merge,
+                                      )
+                                      .merge,
+                                  )
+                                  .merge,
+                              )
+                              .merge,
+                          )
+                          .merge,
+                      )
+                      .merge,
+                  )
+                  .merge,
+              )
+              .merge,
+          ),
+        )((value: Value) =>
+          value match {
+            case sub1: Sub1   =>
+              Right(
+                Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(sub1)))))))))))))))),
+              )
+            case sub2: Sub2   =>
+              Right(
+                Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub2)))))))))))))))),
+              )
+            case sub3: Sub3   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub3))))))))))))))))
+            case sub4: Sub4   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub4)))))))))))))))
+            case sub5: Sub5   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub5))))))))))))))
+            case sub6: Sub6   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub6)))))))))))))
+            case sub7: Sub7   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub7))))))))))))
+            case sub8: Sub8   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub8)))))))))))
+            case sub9: Sub9   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub9))))))))))
+            case sub10: Sub10 => Right(Left(Left(Left(Left(Left(Left(Left(Right(sub10)))))))))
+            case sub11: Sub11 => Right(Left(Left(Left(Left(Left(Left(Right(sub11))))))))
+            case sub12: Sub12 => Right(Left(Left(Left(Left(Left(Right(sub12)))))))
+            case sub13: Sub13 => Right(Left(Left(Left(Left(Right(sub13))))))
+            case sub14: Sub14 => Right(Left(Left(Left(Right(sub14)))))
+            case sub15: Sub15 => Right(Left(Left(Right(sub15))))
+            case sub16: Sub16 => Right(Left(Right(sub16)))
+            case sub17: Sub17 => Right(Right(sub17))
+            case _            => Left(s"Unexpected error type")
+          },
+        )
+
+    def f18[
+      AtomTypes,
+      Sub1 <: Value: ClassTag,
+      Sub2 <: Value: ClassTag,
+      Sub3 <: Value: ClassTag,
+      Sub4 <: Value: ClassTag,
+      Sub5 <: Value: ClassTag,
+      Sub6 <: Value: ClassTag,
+      Sub7 <: Value: ClassTag,
+      Sub8 <: Value: ClassTag,
+      Sub9 <: Value: ClassTag,
+      Sub10 <: Value: ClassTag,
+      Sub11 <: Value: ClassTag,
+      Sub12 <: Value: ClassTag,
+      Sub13 <: Value: ClassTag,
+      Sub14 <: Value: ClassTag,
+      Sub15 <: Value: ClassTag,
+      Sub16 <: Value: ClassTag,
+      Sub17 <: Value: ClassTag,
+      Sub18 <: Value: ClassTag,
+    ](
+      codec1: HttpCodec[AtomTypes, Sub1],
+      codec2: HttpCodec[AtomTypes, Sub2],
+      codec3: HttpCodec[AtomTypes, Sub3],
+      codec4: HttpCodec[AtomTypes, Sub4],
+      codec5: HttpCodec[AtomTypes, Sub5],
+      codec6: HttpCodec[AtomTypes, Sub6],
+      codec7: HttpCodec[AtomTypes, Sub7],
+      codec8: HttpCodec[AtomTypes, Sub8],
+      codec9: HttpCodec[AtomTypes, Sub9],
+      codec10: HttpCodec[AtomTypes, Sub10],
+      codec11: HttpCodec[AtomTypes, Sub11],
+      codec12: HttpCodec[AtomTypes, Sub12],
+      codec13: HttpCodec[AtomTypes, Sub13],
+      codec14: HttpCodec[AtomTypes, Sub14],
+      codec15: HttpCodec[AtomTypes, Sub15],
+      codec16: HttpCodec[AtomTypes, Sub16],
+      codec17: HttpCodec[AtomTypes, Sub17],
+      codec18: HttpCodec[AtomTypes, Sub18],
+    ): HttpCodec[AtomTypes, Value] =
+      (codec1 | codec2 | codec3 | codec4 | codec5 | codec6 | codec7 | codec8 | codec9 | codec10 | codec11 | codec12 | codec13 | codec14 | codec15 | codec16 | codec17 | codec18)
+        .transformOrFail(either =>
+          Right(
+            either.left
+              .map(
+                _.left
+                  .map(
+                    _.left
+                      .map(
+                        _.left
+                          .map(
+                            _.left
+                              .map(
+                                _.left
+                                  .map(
+                                    _.left
+                                      .map(
+                                        _.left
+                                          .map(
+                                            _.left
+                                              .map(
+                                                _.left
+                                                  .map(
+                                                    _.left
+                                                      .map(
+                                                        _.left
+                                                          .map(
+                                                            _.left
+                                                              .map(
+                                                                _.left
+                                                                  .map(_.left.map(_.left.map(_.merge).merge).merge)
+                                                                  .merge,
+                                                              )
+                                                              .merge,
+                                                          )
+                                                          .merge,
+                                                      )
+                                                      .merge,
+                                                  )
+                                                  .merge,
+                                              )
+                                              .merge,
+                                          )
+                                          .merge,
+                                      )
+                                      .merge,
+                                  )
+                                  .merge,
+                              )
+                              .merge,
+                          )
+                          .merge,
+                      )
+                      .merge,
+                  )
+                  .merge,
+              )
+              .merge,
+          ),
+        )((value: Value) =>
+          value match {
+            case sub1: Sub1   =>
+              Right(
+                Left(
+                  Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(sub1)))))))))))))))),
+                ),
+              )
+            case sub2: Sub2   =>
+              Right(
+                Left(
+                  Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub2)))))))))))))))),
+                ),
+              )
+            case sub3: Sub3   =>
+              Right(
+                Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub3)))))))))))))))),
+              )
+            case sub4: Sub4   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub4))))))))))))))))
+            case sub5: Sub5   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub5)))))))))))))))
+            case sub6: Sub6   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub6))))))))))))))
+            case sub7: Sub7   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub7)))))))))))))
+            case sub8: Sub8   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub8))))))))))))
+            case sub9: Sub9   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub9)))))))))))
+            case sub10: Sub10 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub10))))))))))
+            case sub11: Sub11 => Right(Left(Left(Left(Left(Left(Left(Left(Right(sub11)))))))))
+            case sub12: Sub12 => Right(Left(Left(Left(Left(Left(Left(Right(sub12))))))))
+            case sub13: Sub13 => Right(Left(Left(Left(Left(Left(Right(sub13)))))))
+            case sub14: Sub14 => Right(Left(Left(Left(Left(Right(sub14))))))
+            case sub15: Sub15 => Right(Left(Left(Left(Right(sub15)))))
+            case sub16: Sub16 => Right(Left(Left(Right(sub16))))
+            case sub17: Sub17 => Right(Left(Right(sub17)))
+            case sub18: Sub18 => Right(Right(sub18))
+            case _            => Left(s"Unexpected error type")
+          },
+        )
+
+    def f19[
+      AtomTypes,
+      Sub1 <: Value: ClassTag,
+      Sub2 <: Value: ClassTag,
+      Sub3 <: Value: ClassTag,
+      Sub4 <: Value: ClassTag,
+      Sub5 <: Value: ClassTag,
+      Sub6 <: Value: ClassTag,
+      Sub7 <: Value: ClassTag,
+      Sub8 <: Value: ClassTag,
+      Sub9 <: Value: ClassTag,
+      Sub10 <: Value: ClassTag,
+      Sub11 <: Value: ClassTag,
+      Sub12 <: Value: ClassTag,
+      Sub13 <: Value: ClassTag,
+      Sub14 <: Value: ClassTag,
+      Sub15 <: Value: ClassTag,
+      Sub16 <: Value: ClassTag,
+      Sub17 <: Value: ClassTag,
+      Sub18 <: Value: ClassTag,
+      Sub19 <: Value: ClassTag,
+    ](
+      codec1: HttpCodec[AtomTypes, Sub1],
+      codec2: HttpCodec[AtomTypes, Sub2],
+      codec3: HttpCodec[AtomTypes, Sub3],
+      codec4: HttpCodec[AtomTypes, Sub4],
+      codec5: HttpCodec[AtomTypes, Sub5],
+      codec6: HttpCodec[AtomTypes, Sub6],
+      codec7: HttpCodec[AtomTypes, Sub7],
+      codec8: HttpCodec[AtomTypes, Sub8],
+      codec9: HttpCodec[AtomTypes, Sub9],
+      codec10: HttpCodec[AtomTypes, Sub10],
+      codec11: HttpCodec[AtomTypes, Sub11],
+      codec12: HttpCodec[AtomTypes, Sub12],
+      codec13: HttpCodec[AtomTypes, Sub13],
+      codec14: HttpCodec[AtomTypes, Sub14],
+      codec15: HttpCodec[AtomTypes, Sub15],
+      codec16: HttpCodec[AtomTypes, Sub16],
+      codec17: HttpCodec[AtomTypes, Sub17],
+      codec18: HttpCodec[AtomTypes, Sub18],
+      codec19: HttpCodec[AtomTypes, Sub19],
+    ): HttpCodec[AtomTypes, Value] =
+      (codec1 | codec2 | codec3 | codec4 | codec5 | codec6 | codec7 | codec8 | codec9 | codec10 | codec11 | codec12 | codec13 | codec14 | codec15 | codec16 | codec17 | codec18 | codec19)
+        .transformOrFail(either =>
+          Right(
+            either.left
+              .map(
+                _.left
+                  .map(
+                    _.left
+                      .map(
+                        _.left
+                          .map(
+                            _.left
+                              .map(
+                                _.left
+                                  .map(
+                                    _.left
+                                      .map(
+                                        _.left
+                                          .map(
+                                            _.left
+                                              .map(
+                                                _.left
+                                                  .map(
+                                                    _.left
+                                                      .map(
+                                                        _.left
+                                                          .map(
+                                                            _.left
+                                                              .map(
+                                                                _.left
+                                                                  .map(
+                                                                    _.left
+                                                                      .map(_.left.map(_.left.map(_.merge).merge).merge)
+                                                                      .merge,
+                                                                  )
+                                                                  .merge,
+                                                              )
+                                                              .merge,
+                                                          )
+                                                          .merge,
+                                                      )
+                                                      .merge,
+                                                  )
+                                                  .merge,
+                                              )
+                                              .merge,
+                                          )
+                                          .merge,
+                                      )
+                                      .merge,
+                                  )
+                                  .merge,
+                              )
+                              .merge,
+                          )
+                          .merge,
+                      )
+                      .merge,
+                  )
+                  .merge,
+              )
+              .merge,
+          ),
+        )((value: Value) =>
+          value match {
+            case sub1: Sub1   =>
+              Right(
+                Left(
+                  Left(
+                    Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(sub1)))))))))))))))),
+                  ),
+                ),
+              )
+            case sub2: Sub2   =>
+              Right(
+                Left(
+                  Left(
+                    Left(
+                      Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub2))))))))))))))),
+                    ),
+                  ),
+                ),
+              )
+            case sub3: Sub3   =>
+              Right(
+                Left(
+                  Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub3)))))))))))))))),
+                ),
+              )
+            case sub4: Sub4   =>
+              Right(
+                Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub4)))))))))))))))),
+              )
+            case sub5: Sub5   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub5))))))))))))))))
+            case sub6: Sub6   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub6)))))))))))))))
+            case sub7: Sub7   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub7))))))))))))))
+            case sub8: Sub8   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub8)))))))))))))
+            case sub9: Sub9   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub9))))))))))))
+            case sub10: Sub10 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub10)))))))))))
+            case sub11: Sub11 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub11))))))))))
+            case sub12: Sub12 => Right(Left(Left(Left(Left(Left(Left(Left(Right(sub12)))))))))
+            case sub13: Sub13 => Right(Left(Left(Left(Left(Left(Left(Right(sub13))))))))
+            case sub14: Sub14 => Right(Left(Left(Left(Left(Left(Right(sub14)))))))
+            case sub15: Sub15 => Right(Left(Left(Left(Left(Right(sub15))))))
+            case sub16: Sub16 => Right(Left(Left(Left(Right(sub16)))))
+            case sub17: Sub17 => Right(Left(Left(Right(sub17))))
+            case sub18: Sub18 => Right(Left(Right(sub18)))
+            case sub19: Sub19 => Right(Right(sub19))
+            case _            => Left(s"Unexpected error type")
+          },
+        )
+
+    def f20[
+      AtomTypes,
+      Sub1 <: Value: ClassTag,
+      Sub2 <: Value: ClassTag,
+      Sub3 <: Value: ClassTag,
+      Sub4 <: Value: ClassTag,
+      Sub5 <: Value: ClassTag,
+      Sub6 <: Value: ClassTag,
+      Sub7 <: Value: ClassTag,
+      Sub8 <: Value: ClassTag,
+      Sub9 <: Value: ClassTag,
+      Sub10 <: Value: ClassTag,
+      Sub11 <: Value: ClassTag,
+      Sub12 <: Value: ClassTag,
+      Sub13 <: Value: ClassTag,
+      Sub14 <: Value: ClassTag,
+      Sub15 <: Value: ClassTag,
+      Sub16 <: Value: ClassTag,
+      Sub17 <: Value: ClassTag,
+      Sub18 <: Value: ClassTag,
+      Sub19 <: Value: ClassTag,
+      Sub20 <: Value: ClassTag,
+    ](
+      codec1: HttpCodec[AtomTypes, Sub1],
+      codec2: HttpCodec[AtomTypes, Sub2],
+      codec3: HttpCodec[AtomTypes, Sub3],
+      codec4: HttpCodec[AtomTypes, Sub4],
+      codec5: HttpCodec[AtomTypes, Sub5],
+      codec6: HttpCodec[AtomTypes, Sub6],
+      codec7: HttpCodec[AtomTypes, Sub7],
+      codec8: HttpCodec[AtomTypes, Sub8],
+      codec9: HttpCodec[AtomTypes, Sub9],
+      codec10: HttpCodec[AtomTypes, Sub10],
+      codec11: HttpCodec[AtomTypes, Sub11],
+      codec12: HttpCodec[AtomTypes, Sub12],
+      codec13: HttpCodec[AtomTypes, Sub13],
+      codec14: HttpCodec[AtomTypes, Sub14],
+      codec15: HttpCodec[AtomTypes, Sub15],
+      codec16: HttpCodec[AtomTypes, Sub16],
+      codec17: HttpCodec[AtomTypes, Sub17],
+      codec18: HttpCodec[AtomTypes, Sub18],
+      codec19: HttpCodec[AtomTypes, Sub19],
+      codec20: HttpCodec[AtomTypes, Sub20],
+    ): HttpCodec[AtomTypes, Value] =
+      (codec1 | codec2 | codec3 | codec4 | codec5 | codec6 | codec7 | codec8 | codec9 | codec10 | codec11 | codec12 | codec13 | codec14 | codec15 | codec16 | codec17 | codec18 | codec19 | codec20)
+        .transformOrFail(either =>
+          Right(
+            either.left
+              .map(
+                _.left
+                  .map(
+                    _.left
+                      .map(
+                        _.left
+                          .map(
+                            _.left
+                              .map(
+                                _.left
+                                  .map(
+                                    _.left
+                                      .map(
+                                        _.left
+                                          .map(
+                                            _.left
+                                              .map(
+                                                _.left
+                                                  .map(
+                                                    _.left
+                                                      .map(
+                                                        _.left
+                                                          .map(
+                                                            _.left
+                                                              .map(
+                                                                _.left
+                                                                  .map(
+                                                                    _.left
+                                                                      .map(
+                                                                        _.left
+                                                                          .map(
+                                                                            _.left.map(_.left.map(_.merge).merge).merge,
+                                                                          )
+                                                                          .merge,
+                                                                      )
+                                                                      .merge,
+                                                                  )
+                                                                  .merge,
+                                                              )
+                                                              .merge,
+                                                          )
+                                                          .merge,
+                                                      )
+                                                      .merge,
+                                                  )
+                                                  .merge,
+                                              )
+                                              .merge,
+                                          )
+                                          .merge,
+                                      )
+                                      .merge,
+                                  )
+                                  .merge,
+                              )
+                              .merge,
+                          )
+                          .merge,
+                      )
+                      .merge,
+                  )
+                  .merge,
+              )
+              .merge,
+          ),
+        )((value: Value) =>
+          value match {
+            case sub1: Sub1   =>
+              Right(
+                Left(
+                  Left(
+                    Left(
+                      Left(
+                        Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(sub1))))))))))))))),
+                      ),
+                    ),
+                  ),
+                ),
+              )
+            case sub2: Sub2   =>
+              Right(
+                Left(
+                  Left(
+                    Left(
+                      Left(
+                        Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub2))))))))))))))),
+                      ),
+                    ),
+                  ),
+                ),
+              )
+            case sub3: Sub3   =>
+              Right(
+                Left(
+                  Left(
+                    Left(
+                      Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub3))))))))))))))),
+                    ),
+                  ),
+                ),
+              )
+            case sub4: Sub4   =>
+              Right(
+                Left(
+                  Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub4)))))))))))))))),
+                ),
+              )
+            case sub5: Sub5   =>
+              Right(
+                Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub5)))))))))))))))),
+              )
+            case sub6: Sub6   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub6))))))))))))))))
+            case sub7: Sub7   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub7)))))))))))))))
+            case sub8: Sub8   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub8))))))))))))))
+            case sub9: Sub9   => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub9)))))))))))))
+            case sub10: Sub10 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub10))))))))))))
+            case sub11: Sub11 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub11)))))))))))
+            case sub12: Sub12 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub12))))))))))
+            case sub13: Sub13 => Right(Left(Left(Left(Left(Left(Left(Left(Right(sub13)))))))))
+            case sub14: Sub14 => Right(Left(Left(Left(Left(Left(Left(Right(sub14))))))))
+            case sub15: Sub15 => Right(Left(Left(Left(Left(Left(Right(sub15)))))))
+            case sub16: Sub16 => Right(Left(Left(Left(Left(Right(sub16))))))
+            case sub17: Sub17 => Right(Left(Left(Left(Right(sub17)))))
+            case sub18: Sub18 => Right(Left(Left(Right(sub18))))
+            case sub19: Sub19 => Right(Left(Right(sub19)))
+            case sub20: Sub20 => Right(Right(sub20))
+            case _            => Left(s"Unexpected error type")
+          },
+        )
+
+    def f21[
+      AtomTypes,
+      Sub1 <: Value: ClassTag,
+      Sub2 <: Value: ClassTag,
+      Sub3 <: Value: ClassTag,
+      Sub4 <: Value: ClassTag,
+      Sub5 <: Value: ClassTag,
+      Sub6 <: Value: ClassTag,
+      Sub7 <: Value: ClassTag,
+      Sub8 <: Value: ClassTag,
+      Sub9 <: Value: ClassTag,
+      Sub10 <: Value: ClassTag,
+      Sub11 <: Value: ClassTag,
+      Sub12 <: Value: ClassTag,
+      Sub13 <: Value: ClassTag,
+      Sub14 <: Value: ClassTag,
+      Sub15 <: Value: ClassTag,
+      Sub16 <: Value: ClassTag,
+      Sub17 <: Value: ClassTag,
+      Sub18 <: Value: ClassTag,
+      Sub19 <: Value: ClassTag,
+      Sub20 <: Value: ClassTag,
+      Sub21 <: Value: ClassTag,
+    ](
+      codec1: HttpCodec[AtomTypes, Sub1],
+      codec2: HttpCodec[AtomTypes, Sub2],
+      codec3: HttpCodec[AtomTypes, Sub3],
+      codec4: HttpCodec[AtomTypes, Sub4],
+      codec5: HttpCodec[AtomTypes, Sub5],
+      codec6: HttpCodec[AtomTypes, Sub6],
+      codec7: HttpCodec[AtomTypes, Sub7],
+      codec8: HttpCodec[AtomTypes, Sub8],
+      codec9: HttpCodec[AtomTypes, Sub9],
+      codec10: HttpCodec[AtomTypes, Sub10],
+      codec11: HttpCodec[AtomTypes, Sub11],
+      codec12: HttpCodec[AtomTypes, Sub12],
+      codec13: HttpCodec[AtomTypes, Sub13],
+      codec14: HttpCodec[AtomTypes, Sub14],
+      codec15: HttpCodec[AtomTypes, Sub15],
+      codec16: HttpCodec[AtomTypes, Sub16],
+      codec17: HttpCodec[AtomTypes, Sub17],
+      codec18: HttpCodec[AtomTypes, Sub18],
+      codec19: HttpCodec[AtomTypes, Sub19],
+      codec20: HttpCodec[AtomTypes, Sub20],
+      codec21: HttpCodec[AtomTypes, Sub21],
+    ): HttpCodec[AtomTypes, Value] =
+      (codec1 | codec2 | codec3 | codec4 | codec5 | codec6 | codec7 | codec8 | codec9 | codec10 | codec11 | codec12 | codec13 | codec14 | codec15 | codec16 | codec17 | codec18 | codec19 | codec20 | codec21)
+        .transformOrFail(either =>
+          Right(
+            either.left
+              .map(
+                _.left
+                  .map(
+                    _.left
+                      .map(
+                        _.left
+                          .map(
+                            _.left
+                              .map(
+                                _.left
+                                  .map(
+                                    _.left
+                                      .map(
+                                        _.left
+                                          .map(
+                                            _.left
+                                              .map(
+                                                _.left
+                                                  .map(
+                                                    _.left
+                                                      .map(
+                                                        _.left
+                                                          .map(
+                                                            _.left
+                                                              .map(
+                                                                _.left
+                                                                  .map(
+                                                                    _.left
+                                                                      .map(
+                                                                        _.left
+                                                                          .map(
+                                                                            _.left
+                                                                              .map(
+                                                                                _.left
+                                                                                  .map(_.left.map(_.merge).merge)
+                                                                                  .merge,
+                                                                              )
+                                                                              .merge,
+                                                                          )
+                                                                          .merge,
+                                                                      )
+                                                                      .merge,
+                                                                  )
+                                                                  .merge,
+                                                              )
+                                                              .merge,
+                                                          )
+                                                          .merge,
+                                                      )
+                                                      .merge,
+                                                  )
+                                                  .merge,
+                                              )
+                                              .merge,
+                                          )
+                                          .merge,
+                                      )
+                                      .merge,
+                                  )
+                                  .merge,
+                              )
+                              .merge,
+                          )
+                          .merge,
+                      )
+                      .merge,
+                  )
+                  .merge,
+              )
+              .merge,
+          ),
+        )((value: Value) =>
+          value match {
+            case sub1: Sub1   =>
+              Right(
+                Left(
+                  Left(
+                    Left(
+                      Left(
+                        Left(
+                          Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(sub1))))))))))))))),
+                        ),
+                      ),
+                    ),
+                  ),
+                ),
+              )
+            case sub2: Sub2   =>
+              Right(
+                Left(
+                  Left(
+                    Left(
+                      Left(
+                        Left(
+                          Left(
+                            Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub2)))))))))))))),
+                          ),
+                        ),
+                      ),
+                    ),
+                  ),
+                ),
+              )
+            case sub3: Sub3   =>
+              Right(
+                Left(
+                  Left(
+                    Left(
+                      Left(
+                        Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub3))))))))))))))),
+                      ),
+                    ),
+                  ),
+                ),
+              )
+            case sub4: Sub4   =>
+              Right(
+                Left(
+                  Left(
+                    Left(
+                      Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub4))))))))))))))),
+                    ),
+                  ),
+                ),
+              )
+            case sub5: Sub5   =>
+              Right(
+                Left(
+                  Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub5)))))))))))))))),
+                ),
+              )
+            case sub6: Sub6   =>
+              Right(
+                Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub6)))))))))))))))),
+              )
+            case sub7: Sub7   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub7))))))))))))))))
+            case sub8: Sub8   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub8)))))))))))))))
+            case sub9: Sub9   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub9))))))))))))))
+            case sub10: Sub10 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub10)))))))))))))
+            case sub11: Sub11 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub11))))))))))))
+            case sub12: Sub12 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub12)))))))))))
+            case sub13: Sub13 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub13))))))))))
+            case sub14: Sub14 => Right(Left(Left(Left(Left(Left(Left(Left(Right(sub14)))))))))
+            case sub15: Sub15 => Right(Left(Left(Left(Left(Left(Left(Right(sub15))))))))
+            case sub16: Sub16 => Right(Left(Left(Left(Left(Left(Right(sub16)))))))
+            case sub17: Sub17 => Right(Left(Left(Left(Left(Right(sub17))))))
+            case sub18: Sub18 => Right(Left(Left(Left(Right(sub18)))))
+            case sub19: Sub19 => Right(Left(Left(Right(sub19))))
+            case sub20: Sub20 => Right(Left(Right(sub20)))
+            case sub21: Sub21 => Right(Right(sub21))
+            case _            => Left(s"Unexpected error type")
+          },
+        )
+
+    def f22[
+      AtomTypes,
+      Sub1 <: Value: ClassTag,
+      Sub2 <: Value: ClassTag,
+      Sub3 <: Value: ClassTag,
+      Sub4 <: Value: ClassTag,
+      Sub5 <: Value: ClassTag,
+      Sub6 <: Value: ClassTag,
+      Sub7 <: Value: ClassTag,
+      Sub8 <: Value: ClassTag,
+      Sub9 <: Value: ClassTag,
+      Sub10 <: Value: ClassTag,
+      Sub11 <: Value: ClassTag,
+      Sub12 <: Value: ClassTag,
+      Sub13 <: Value: ClassTag,
+      Sub14 <: Value: ClassTag,
+      Sub15 <: Value: ClassTag,
+      Sub16 <: Value: ClassTag,
+      Sub17 <: Value: ClassTag,
+      Sub18 <: Value: ClassTag,
+      Sub19 <: Value: ClassTag,
+      Sub20 <: Value: ClassTag,
+      Sub21 <: Value: ClassTag,
+      Sub22 <: Value: ClassTag,
+    ](
+      codec1: HttpCodec[AtomTypes, Sub1],
+      codec2: HttpCodec[AtomTypes, Sub2],
+      codec3: HttpCodec[AtomTypes, Sub3],
+      codec4: HttpCodec[AtomTypes, Sub4],
+      codec5: HttpCodec[AtomTypes, Sub5],
+      codec6: HttpCodec[AtomTypes, Sub6],
+      codec7: HttpCodec[AtomTypes, Sub7],
+      codec8: HttpCodec[AtomTypes, Sub8],
+      codec9: HttpCodec[AtomTypes, Sub9],
+      codec10: HttpCodec[AtomTypes, Sub10],
+      codec11: HttpCodec[AtomTypes, Sub11],
+      codec12: HttpCodec[AtomTypes, Sub12],
+      codec13: HttpCodec[AtomTypes, Sub13],
+      codec14: HttpCodec[AtomTypes, Sub14],
+      codec15: HttpCodec[AtomTypes, Sub15],
+      codec16: HttpCodec[AtomTypes, Sub16],
+      codec17: HttpCodec[AtomTypes, Sub17],
+      codec18: HttpCodec[AtomTypes, Sub18],
+      codec19: HttpCodec[AtomTypes, Sub19],
+      codec20: HttpCodec[AtomTypes, Sub20],
+      codec21: HttpCodec[AtomTypes, Sub21],
+      codec22: HttpCodec[AtomTypes, Sub22],
+    ): HttpCodec[AtomTypes, Value] =
+      (codec1 | codec2 | codec3 | codec4 | codec5 | codec6 | codec7 | codec8 | codec9 | codec10 | codec11 | codec12 | codec13 | codec14 | codec15 | codec16 | codec17 | codec18 | codec19 | codec20 | codec21 | codec22)
+        .transformOrFail(either =>
+          Right(
+            either.left
+              .map(
+                _.left
+                  .map(
+                    _.left
+                      .map(
+                        _.left
+                          .map(
+                            _.left
+                              .map(
+                                _.left
+                                  .map(
+                                    _.left
+                                      .map(
+                                        _.left
+                                          .map(
+                                            _.left
+                                              .map(
+                                                _.left
+                                                  .map(
+                                                    _.left
+                                                      .map(
+                                                        _.left
+                                                          .map(
+                                                            _.left
+                                                              .map(
+                                                                _.left
+                                                                  .map(
+                                                                    _.left
+                                                                      .map(
+                                                                        _.left
+                                                                          .map(
+                                                                            _.left
+                                                                              .map(
+                                                                                _.left
+                                                                                  .map(
+                                                                                    _.left
+                                                                                      .map(_.left.map(_.merge).merge)
+                                                                                      .merge,
+                                                                                  )
+                                                                                  .merge,
+                                                                              )
+                                                                              .merge,
+                                                                          )
+                                                                          .merge,
+                                                                      )
+                                                                      .merge,
+                                                                  )
+                                                                  .merge,
+                                                              )
+                                                              .merge,
+                                                          )
+                                                          .merge,
+                                                      )
+                                                      .merge,
+                                                  )
+                                                  .merge,
+                                              )
+                                              .merge,
+                                          )
+                                          .merge,
+                                      )
+                                      .merge,
+                                  )
+                                  .merge,
+                              )
+                              .merge,
+                          )
+                          .merge,
+                      )
+                      .merge,
+                  )
+                  .merge,
+              )
+              .merge,
+          ),
+        )((value: Value) =>
+          value match {
+            case sub1: Sub1   =>
+              Right(
+                Left(
+                  Left(
+                    Left(
+                      Left(
+                        Left(
+                          Left(
+                            Left(
+                              Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(sub1)))))))))))))),
+                            ),
+                          ),
+                        ),
+                      ),
+                    ),
+                  ),
+                ),
+              )
+            case sub2: Sub2   =>
+              Right(
+                Left(
+                  Left(
+                    Left(
+                      Left(
+                        Left(
+                          Left(
+                            Left(
+                              Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub2)))))))))))))),
+                            ),
+                          ),
+                        ),
+                      ),
+                    ),
+                  ),
+                ),
+              )
+            case sub3: Sub3   =>
+              Right(
+                Left(
+                  Left(
+                    Left(
+                      Left(
+                        Left(
+                          Left(
+                            Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub3)))))))))))))),
+                          ),
+                        ),
+                      ),
+                    ),
+                  ),
+                ),
+              )
+            case sub4: Sub4   =>
+              Right(
+                Left(
+                  Left(
+                    Left(
+                      Left(
+                        Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub4))))))))))))))),
+                      ),
+                    ),
+                  ),
+                ),
+              )
+            case sub5: Sub5   =>
+              Right(
+                Left(
+                  Left(
+                    Left(
+                      Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub5))))))))))))))),
+                    ),
+                  ),
+                ),
+              )
+            case sub6: Sub6   =>
+              Right(
+                Left(
+                  Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub6)))))))))))))))),
+                ),
+              )
+            case sub7: Sub7   =>
+              Right(
+                Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub7)))))))))))))))),
+              )
+            case sub8: Sub8   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub8))))))))))))))))
+            case sub9: Sub9   =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub9)))))))))))))))
+            case sub10: Sub10 =>
+              Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub10))))))))))))))
+            case sub11: Sub11 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub11)))))))))))))
+            case sub12: Sub12 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub12))))))))))))
+            case sub13: Sub13 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub13)))))))))))
+            case sub14: Sub14 => Right(Left(Left(Left(Left(Left(Left(Left(Left(Right(sub14))))))))))
+            case sub15: Sub15 => Right(Left(Left(Left(Left(Left(Left(Left(Right(sub15)))))))))
+            case sub16: Sub16 => Right(Left(Left(Left(Left(Left(Left(Right(sub16))))))))
+            case sub17: Sub17 => Right(Left(Left(Left(Left(Left(Right(sub17)))))))
+            case sub18: Sub18 => Right(Left(Left(Left(Left(Right(sub18))))))
+            case sub19: Sub19 => Right(Left(Left(Left(Right(sub19)))))
+            case sub20: Sub20 => Right(Left(Left(Right(sub20))))
+            case sub21: Sub21 => Right(Left(Right(sub21)))
+            case sub22: Sub22 => Right(Right(sub22))
+            case _            => Left(s"Unexpected error type")
+          },
+        )
+
   }
 
   private[http] sealed trait Atom[-AtomTypes, Value0] extends HttpCodec[AtomTypes, Value0] {
@@ -566,6 +2240,19 @@ object HttpCodec extends ContentCodecs with HeaderCodecs with MethodCodecs with
     def tag: AtomTag = AtomTag.Content
 
     def index(index: Int): Content[A] = copy(index = index)
+
+    /**
+     * Returns a new codec, where the value produced by this one is optional.
+     */
+    override def optional: HttpCodec[HttpCodecType.Content, Option[A]] =
+      Annotated(
+        Content(
+          codec.optional,
+          name,
+          index,
+        ),
+        Metadata.Optional(),
+      )
   }
   private[http] final case class ContentStream[A](
     codec: HttpContentCodec[A],
diff --git a/zio-http/shared/src/main/scala/zio/http/codec/HttpContentCodec.scala b/zio-http/shared/src/main/scala/zio/http/codec/HttpContentCodec.scala
index c0223e4fe6..3f8a3f29a2 100644
--- a/zio-http/shared/src/main/scala/zio/http/codec/HttpContentCodec.scala
+++ b/zio-http/shared/src/main/scala/zio/http/codec/HttpContentCodec.scala
@@ -148,6 +148,36 @@ sealed trait HttpContentCodec[A] { self =>
     choices.headOption.map(_._2).getOrElse {
       throw new IllegalArgumentException(s"No codec defined")
     }
+
+  def optional: HttpContentCodec[Option[A]] =
+    self match {
+      case HttpContentCodec.Choices(choices)           =>
+        HttpContentCodec.Choices(
+          choices.map { case (mediaType, BinaryCodecWithSchema(fromConfig, schema)) =>
+            mediaType -> BinaryCodecWithSchema(fromConfig.andThen(optBinaryCodec), schema.optional)
+          },
+        )
+      case HttpContentCodec.Filtered(codec, mediaType) =>
+        HttpContentCodec.Filtered(codec.optional, mediaType)
+    }
+
+  private def optBinaryCodec(bc: BinaryCodec[A]): BinaryCodec[Option[A]] = new BinaryCodec[Option[A]] {
+    override def encode(value: Option[A]): Chunk[Byte] = value match {
+      case Some(a) => bc.encode(a)
+      case None    => Chunk.empty
+    }
+
+    override def decode(bytes: Chunk[Byte]): Either[DecodeError, Option[A]] =
+      if (bytes.isEmpty) Right(None)
+      else bc.decode(bytes).map(Some(_))
+
+    override def streamDecoder: ZPipeline[Any, DecodeError, Byte, Option[A]] =
+      ZPipeline.chunks[Byte].map(bc.decode).map(_.toOption)
+
+    override def streamEncoder: ZPipeline[Any, Nothing, Option[A], Byte] =
+      ZPipeline.identity[Option[A]].map(_.fold(Chunk.empty[Byte])(bc.encode)).flattenChunks
+  }
+
 }
 
 object HttpContentCodec {
diff --git a/zio-http/shared/src/main/scala/zio/http/codec/PathCodec.scala b/zio-http/shared/src/main/scala/zio/http/codec/PathCodec.scala
index ead97b5da7..75c7e34140 100644
--- a/zio-http/shared/src/main/scala/zio/http/codec/PathCodec.scala
+++ b/zio-http/shared/src/main/scala/zio/http/codec/PathCodec.scala
@@ -48,8 +48,11 @@ sealed trait PathCodec[A] extends codec.PathCodecPlatformSpecific { self =>
   final def ++[B](that: PathCodec[B])(implicit combiner: Combiner[A, B]): PathCodec[combiner.Out] =
     PathCodec.Concat(self, that, combiner)
 
-  final def /[B](that: PathCodec[B])(implicit combiner: Combiner[A, B]): PathCodec[combiner.Out] =
-    self ++ that
+  final def /[B](that: PathCodec[B])(implicit combiner: Combiner[A, B]): PathCodec[combiner.Out] = {
+    if (self == PathCodec.empty) that.asInstanceOf[PathCodec[combiner.Out]]
+    else if (that == PathCodec.empty) self.asInstanceOf[PathCodec[combiner.Out]]
+    else self ++ that
+  }
 
   final def /[Env, Err](routes: Routes[Env, Err])(implicit
     ev: PathCodec[A] <:< PathCodec[Unit],
diff --git a/zio-http/shared/src/main/scala/zio/http/codec/SegmentCodec.scala b/zio-http/shared/src/main/scala/zio/http/codec/SegmentCodec.scala
index a8077c6b64..e60ea41f8c 100644
--- a/zio-http/shared/src/main/scala/zio/http/codec/SegmentCodec.scala
+++ b/zio-http/shared/src/main/scala/zio/http/codec/SegmentCodec.scala
@@ -114,6 +114,7 @@ sealed trait SegmentCodec[A] { self =>
     }
     if (self ne SegmentCodec.Empty) b.append('/')
     loop(self.asInstanceOf[SegmentCodec[_]])
+    if (b.isEmpty) b.appendAll("/")
     b.result()
   }
 
diff --git a/zio-http/shared/src/main/scala/zio/http/endpoint/Endpoint.scala b/zio-http/shared/src/main/scala/zio/http/endpoint/Endpoint.scala
index 95a0222b9a..7d3f094265 100644
--- a/zio-http/shared/src/main/scala/zio/http/endpoint/Endpoint.scala
+++ b/zio-http/shared/src/main/scala/zio/http/endpoint/Endpoint.scala
@@ -979,6 +979,751 @@ object Endpoint {
       val codec = HttpCodec.enumeration.f8(codec1, codec2, codec3, codec4, codec5, codec6, codec7, codec8)
       self.copy[PathInput, Input, alt.Out, Output, Auth](error = codec | self.error)
     }
+
+    // apply 9
+    def apply[
+      Sub1 <: Err2: ClassTag,
+      Sub2 <: Err2: ClassTag,
+      Sub3 <: Err2: ClassTag,
+      Sub4 <: Err2: ClassTag,
+      Sub5 <: Err2: ClassTag,
+      Sub6 <: Err2: ClassTag,
+      Sub7 <: Err2: ClassTag,
+      Sub8 <: Err2: ClassTag,
+      Sub9 <: Err2: ClassTag,
+    ](
+      codec1: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub1],
+      codec2: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub2],
+      codec3: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub3],
+      codec4: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub4],
+      codec5: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub5],
+      codec6: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub6],
+      codec7: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub7],
+      codec8: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub8],
+      codec9: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub9],
+    )(implicit alt: Alternator[Err2, Err]): Endpoint[PathInput, Input, alt.Out, Output, Auth] = {
+      val codec = HttpCodec.enumeration.f9(codec1, codec2, codec3, codec4, codec5, codec6, codec7, codec8, codec9)
+      self.copy[PathInput, Input, alt.Out, Output, Auth](error = codec | self.error)
+    }
+
+    def apply[
+      Sub1 <: Err2: ClassTag,
+      Sub2 <: Err2: ClassTag,
+      Sub3 <: Err2: ClassTag,
+      Sub4 <: Err2: ClassTag,
+      Sub5 <: Err2: ClassTag,
+      Sub6 <: Err2: ClassTag,
+      Sub7 <: Err2: ClassTag,
+      Sub8 <: Err2: ClassTag,
+      Sub9 <: Err2: ClassTag,
+      Sub10 <: Err2: ClassTag,
+    ](
+      codec1: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub1],
+      codec2: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub2],
+      codec3: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub3],
+      codec4: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub4],
+      codec5: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub5],
+      codec6: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub6],
+      codec7: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub7],
+      codec8: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub8],
+      codec9: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub9],
+      codec10: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub10],
+    )(implicit alt: Alternator[Err2, Err]): Endpoint[PathInput, Input, alt.Out, Output, Auth] = {
+      val codec =
+        HttpCodec.enumeration.f10(codec1, codec2, codec3, codec4, codec5, codec6, codec7, codec8, codec9, codec10)
+      self.copy[PathInput, Input, alt.Out, Output, Auth](error = codec | self.error)
+    }
+
+    def apply[
+      Sub1 <: Err2: ClassTag,
+      Sub2 <: Err2: ClassTag,
+      Sub3 <: Err2: ClassTag,
+      Sub4 <: Err2: ClassTag,
+      Sub5 <: Err2: ClassTag,
+      Sub6 <: Err2: ClassTag,
+      Sub7 <: Err2: ClassTag,
+      Sub8 <: Err2: ClassTag,
+      Sub9 <: Err2: ClassTag,
+      Sub10 <: Err2: ClassTag,
+      Sub11 <: Err2: ClassTag,
+    ](
+      codec1: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub1],
+      codec2: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub2],
+      codec3: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub3],
+      codec4: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub4],
+      codec5: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub5],
+      codec6: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub6],
+      codec7: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub7],
+      codec8: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub8],
+      codec9: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub9],
+      codec10: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub10],
+      codec11: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub11],
+    )(implicit alt: Alternator[Err2, Err]): Endpoint[PathInput, Input, alt.Out, Output, Auth] = {
+      val codec = HttpCodec.enumeration.f11(
+        codec1,
+        codec2,
+        codec3,
+        codec4,
+        codec5,
+        codec6,
+        codec7,
+        codec8,
+        codec9,
+        codec10,
+        codec11,
+      )
+      self.copy[PathInput, Input, alt.Out, Output, Auth](error = codec | self.error)
+    }
+
+    def apply[
+      Sub1 <: Err2: ClassTag,
+      Sub2 <: Err2: ClassTag,
+      Sub3 <: Err2: ClassTag,
+      Sub4 <: Err2: ClassTag,
+      Sub5 <: Err2: ClassTag,
+      Sub6 <: Err2: ClassTag,
+      Sub7 <: Err2: ClassTag,
+      Sub8 <: Err2: ClassTag,
+      Sub9 <: Err2: ClassTag,
+      Sub10 <: Err2: ClassTag,
+      Sub11 <: Err2: ClassTag,
+      Sub12 <: Err2: ClassTag,
+    ](
+      codec1: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub1],
+      codec2: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub2],
+      codec3: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub3],
+      codec4: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub4],
+      codec5: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub5],
+      codec6: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub6],
+      codec7: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub7],
+      codec8: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub8],
+      codec9: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub9],
+      codec10: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub10],
+      codec11: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub11],
+      codec12: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub12],
+    )(implicit alt: Alternator[Err2, Err]): Endpoint[PathInput, Input, alt.Out, Output, Auth] = {
+      val codec = HttpCodec.enumeration.f12(
+        codec1,
+        codec2,
+        codec3,
+        codec4,
+        codec5,
+        codec6,
+        codec7,
+        codec8,
+        codec9,
+        codec10,
+        codec11,
+        codec12,
+      )
+      self.copy[PathInput, Input, alt.Out, Output, Auth](error = codec | self.error)
+    }
+
+    def apply[
+      Sub1 <: Err2: ClassTag,
+      Sub2 <: Err2: ClassTag,
+      Sub3 <: Err2: ClassTag,
+      Sub4 <: Err2: ClassTag,
+      Sub5 <: Err2: ClassTag,
+      Sub6 <: Err2: ClassTag,
+      Sub7 <: Err2: ClassTag,
+      Sub8 <: Err2: ClassTag,
+      Sub9 <: Err2: ClassTag,
+      Sub10 <: Err2: ClassTag,
+      Sub11 <: Err2: ClassTag,
+      Sub12 <: Err2: ClassTag,
+      Sub13 <: Err2: ClassTag,
+    ](
+      codec1: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub1],
+      codec2: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub2],
+      codec3: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub3],
+      codec4: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub4],
+      codec5: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub5],
+      codec6: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub6],
+      codec7: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub7],
+      codec8: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub8],
+      codec9: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub9],
+      codec10: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub10],
+      codec11: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub11],
+      codec12: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub12],
+      codec13: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub13],
+    )(implicit alt: Alternator[Err2, Err]): Endpoint[PathInput, Input, alt.Out, Output, Auth] = {
+      val codec = HttpCodec.enumeration.f13(
+        codec1,
+        codec2,
+        codec3,
+        codec4,
+        codec5,
+        codec6,
+        codec7,
+        codec8,
+        codec9,
+        codec10,
+        codec11,
+        codec12,
+        codec13,
+      )
+      self.copy[PathInput, Input, alt.Out, Output, Auth](error = codec | self.error)
+    }
+
+    def apply[
+      Sub1 <: Err2: ClassTag,
+      Sub2 <: Err2: ClassTag,
+      Sub3 <: Err2: ClassTag,
+      Sub4 <: Err2: ClassTag,
+      Sub5 <: Err2: ClassTag,
+      Sub6 <: Err2: ClassTag,
+      Sub7 <: Err2: ClassTag,
+      Sub8 <: Err2: ClassTag,
+      Sub9 <: Err2: ClassTag,
+      Sub10 <: Err2: ClassTag,
+      Sub11 <: Err2: ClassTag,
+      Sub12 <: Err2: ClassTag,
+      Sub13 <: Err2: ClassTag,
+      Sub14 <: Err2: ClassTag,
+    ](
+      codec1: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub1],
+      codec2: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub2],
+      codec3: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub3],
+      codec4: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub4],
+      codec5: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub5],
+      codec6: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub6],
+      codec7: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub7],
+      codec8: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub8],
+      codec9: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub9],
+      codec10: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub10],
+      codec11: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub11],
+      codec12: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub12],
+      codec13: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub13],
+      codec14: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub14],
+    )(implicit alt: Alternator[Err2, Err]): Endpoint[PathInput, Input, alt.Out, Output, Auth] = {
+      val codec = HttpCodec.enumeration.f14(
+        codec1,
+        codec2,
+        codec3,
+        codec4,
+        codec5,
+        codec6,
+        codec7,
+        codec8,
+        codec9,
+        codec10,
+        codec11,
+        codec12,
+        codec13,
+        codec14,
+      )
+      self.copy[PathInput, Input, alt.Out, Output, Auth](error = codec | self.error)
+    }
+
+    def apply[
+      Sub1 <: Err2: ClassTag,
+      Sub2 <: Err2: ClassTag,
+      Sub3 <: Err2: ClassTag,
+      Sub4 <: Err2: ClassTag,
+      Sub5 <: Err2: ClassTag,
+      Sub6 <: Err2: ClassTag,
+      Sub7 <: Err2: ClassTag,
+      Sub8 <: Err2: ClassTag,
+      Sub9 <: Err2: ClassTag,
+      Sub10 <: Err2: ClassTag,
+      Sub11 <: Err2: ClassTag,
+      Sub12 <: Err2: ClassTag,
+      Sub13 <: Err2: ClassTag,
+      Sub14 <: Err2: ClassTag,
+      Sub15 <: Err2: ClassTag,
+    ](
+      codec1: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub1],
+      codec2: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub2],
+      codec3: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub3],
+      codec4: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub4],
+      codec5: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub5],
+      codec6: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub6],
+      codec7: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub7],
+      codec8: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub8],
+      codec9: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub9],
+      codec10: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub10],
+      codec11: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub11],
+      codec12: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub12],
+      codec13: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub13],
+      codec14: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub14],
+      codec15: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub15],
+    )(implicit alt: Alternator[Err2, Err]): Endpoint[PathInput, Input, alt.Out, Output, Auth] = {
+      val codec = HttpCodec.enumeration.f15(
+        codec1,
+        codec2,
+        codec3,
+        codec4,
+        codec5,
+        codec6,
+        codec7,
+        codec8,
+        codec9,
+        codec10,
+        codec11,
+        codec12,
+        codec13,
+        codec14,
+        codec15,
+      )
+      self.copy[PathInput, Input, alt.Out, Output, Auth](error = codec | self.error)
+    }
+
+    def apply[
+      Sub1 <: Err2: ClassTag,
+      Sub2 <: Err2: ClassTag,
+      Sub3 <: Err2: ClassTag,
+      Sub4 <: Err2: ClassTag,
+      Sub5 <: Err2: ClassTag,
+      Sub6 <: Err2: ClassTag,
+      Sub7 <: Err2: ClassTag,
+      Sub8 <: Err2: ClassTag,
+      Sub9 <: Err2: ClassTag,
+      Sub10 <: Err2: ClassTag,
+      Sub11 <: Err2: ClassTag,
+      Sub12 <: Err2: ClassTag,
+      Sub13 <: Err2: ClassTag,
+      Sub14 <: Err2: ClassTag,
+      Sub15 <: Err2: ClassTag,
+      Sub16 <: Err2: ClassTag,
+    ](
+      codec1: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub1],
+      codec2: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub2],
+      codec3: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub3],
+      codec4: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub4],
+      codec5: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub5],
+      codec6: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub6],
+      codec7: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub7],
+      codec8: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub8],
+      codec9: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub9],
+      codec10: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub10],
+      codec11: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub11],
+      codec12: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub12],
+      codec13: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub13],
+      codec14: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub14],
+      codec15: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub15],
+      codec16: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub16],
+    )(implicit alt: Alternator[Err2, Err]): Endpoint[PathInput, Input, alt.Out, Output, Auth] = {
+      val codec = HttpCodec.enumeration.f16(
+        codec1,
+        codec2,
+        codec3,
+        codec4,
+        codec5,
+        codec6,
+        codec7,
+        codec8,
+        codec9,
+        codec10,
+        codec11,
+        codec12,
+        codec13,
+        codec14,
+        codec15,
+        codec16,
+      )
+      self.copy[PathInput, Input, alt.Out, Output, Auth](error = codec | self.error)
+    }
+
+    def apply[
+      Sub1 <: Err2: ClassTag,
+      Sub2 <: Err2: ClassTag,
+      Sub3 <: Err2: ClassTag,
+      Sub4 <: Err2: ClassTag,
+      Sub5 <: Err2: ClassTag,
+      Sub6 <: Err2: ClassTag,
+      Sub7 <: Err2: ClassTag,
+      Sub8 <: Err2: ClassTag,
+      Sub9 <: Err2: ClassTag,
+      Sub10 <: Err2: ClassTag,
+      Sub11 <: Err2: ClassTag,
+      Sub12 <: Err2: ClassTag,
+      Sub13 <: Err2: ClassTag,
+      Sub14 <: Err2: ClassTag,
+      Sub15 <: Err2: ClassTag,
+      Sub16 <: Err2: ClassTag,
+      Sub17 <: Err2: ClassTag,
+    ](
+      codec1: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub1],
+      codec2: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub2],
+      codec3: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub3],
+      codec4: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub4],
+      codec5: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub5],
+      codec6: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub6],
+      codec7: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub7],
+      codec8: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub8],
+      codec9: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub9],
+      codec10: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub10],
+      codec11: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub11],
+      codec12: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub12],
+      codec13: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub13],
+      codec14: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub14],
+      codec15: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub15],
+      codec16: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub16],
+      codec17: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub17],
+    )(implicit alt: Alternator[Err2, Err]): Endpoint[PathInput, Input, alt.Out, Output, Auth] = {
+      val codec = HttpCodec.enumeration.f17(
+        codec1,
+        codec2,
+        codec3,
+        codec4,
+        codec5,
+        codec6,
+        codec7,
+        codec8,
+        codec9,
+        codec10,
+        codec11,
+        codec12,
+        codec13,
+        codec14,
+        codec15,
+        codec16,
+        codec17,
+      )
+      self.copy[PathInput, Input, alt.Out, Output, Auth](error = codec | self.error)
+    }
+
+    def apply[
+      Sub1 <: Err2: ClassTag,
+      Sub2 <: Err2: ClassTag,
+      Sub3 <: Err2: ClassTag,
+      Sub4 <: Err2: ClassTag,
+      Sub5 <: Err2: ClassTag,
+      Sub6 <: Err2: ClassTag,
+      Sub7 <: Err2: ClassTag,
+      Sub8 <: Err2: ClassTag,
+      Sub9 <: Err2: ClassTag,
+      Sub10 <: Err2: ClassTag,
+      Sub11 <: Err2: ClassTag,
+      Sub12 <: Err2: ClassTag,
+      Sub13 <: Err2: ClassTag,
+      Sub14 <: Err2: ClassTag,
+      Sub15 <: Err2: ClassTag,
+      Sub16 <: Err2: ClassTag,
+      Sub17 <: Err2: ClassTag,
+      Sub18 <: Err2: ClassTag,
+    ](
+      codec1: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub1],
+      codec2: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub2],
+      codec3: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub3],
+      codec4: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub4],
+      codec5: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub5],
+      codec6: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub6],
+      codec7: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub7],
+      codec8: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub8],
+      codec9: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub9],
+      codec10: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub10],
+      codec11: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub11],
+      codec12: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub12],
+      codec13: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub13],
+      codec14: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub14],
+      codec15: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub15],
+      codec16: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub16],
+      codec17: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub17],
+      codec18: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub18],
+    )(implicit alt: Alternator[Err2, Err]): Endpoint[PathInput, Input, alt.Out, Output, Auth] = {
+      val codec = HttpCodec.enumeration.f18(
+        codec1,
+        codec2,
+        codec3,
+        codec4,
+        codec5,
+        codec6,
+        codec7,
+        codec8,
+        codec9,
+        codec10,
+        codec11,
+        codec12,
+        codec13,
+        codec14,
+        codec15,
+        codec16,
+        codec17,
+        codec18,
+      )
+      self.copy[PathInput, Input, alt.Out, Output, Auth](error = codec | self.error)
+    }
+
+    def apply[
+      Sub1 <: Err2: ClassTag,
+      Sub2 <: Err2: ClassTag,
+      Sub3 <: Err2: ClassTag,
+      Sub4 <: Err2: ClassTag,
+      Sub5 <: Err2: ClassTag,
+      Sub6 <: Err2: ClassTag,
+      Sub7 <: Err2: ClassTag,
+      Sub8 <: Err2: ClassTag,
+      Sub9 <: Err2: ClassTag,
+      Sub10 <: Err2: ClassTag,
+      Sub11 <: Err2: ClassTag,
+      Sub12 <: Err2: ClassTag,
+      Sub13 <: Err2: ClassTag,
+      Sub14 <: Err2: ClassTag,
+      Sub15 <: Err2: ClassTag,
+      Sub16 <: Err2: ClassTag,
+      Sub17 <: Err2: ClassTag,
+      Sub18 <: Err2: ClassTag,
+      Sub19 <: Err2: ClassTag,
+    ](
+      codec1: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub1],
+      codec2: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub2],
+      codec3: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub3],
+      codec4: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub4],
+      codec5: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub5],
+      codec6: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub6],
+      codec7: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub7],
+      codec8: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub8],
+      codec9: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub9],
+      codec10: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub10],
+      codec11: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub11],
+      codec12: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub12],
+      codec13: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub13],
+      codec14: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub14],
+      codec15: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub15],
+      codec16: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub16],
+      codec17: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub17],
+      codec18: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub18],
+      codec19: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub19],
+    )(implicit alt: Alternator[Err2, Err]): Endpoint[PathInput, Input, alt.Out, Output, Auth] = {
+      val codec = HttpCodec.enumeration.f19(
+        codec1,
+        codec2,
+        codec3,
+        codec4,
+        codec5,
+        codec6,
+        codec7,
+        codec8,
+        codec9,
+        codec10,
+        codec11,
+        codec12,
+        codec13,
+        codec14,
+        codec15,
+        codec16,
+        codec17,
+        codec18,
+        codec19,
+      )
+      self.copy[PathInput, Input, alt.Out, Output, Auth](error = codec | self.error)
+    }
+
+    def apply[
+      Sub1 <: Err2: ClassTag,
+      Sub2 <: Err2: ClassTag,
+      Sub3 <: Err2: ClassTag,
+      Sub4 <: Err2: ClassTag,
+      Sub5 <: Err2: ClassTag,
+      Sub6 <: Err2: ClassTag,
+      Sub7 <: Err2: ClassTag,
+      Sub8 <: Err2: ClassTag,
+      Sub9 <: Err2: ClassTag,
+      Sub10 <: Err2: ClassTag,
+      Sub11 <: Err2: ClassTag,
+      Sub12 <: Err2: ClassTag,
+      Sub13 <: Err2: ClassTag,
+      Sub14 <: Err2: ClassTag,
+      Sub15 <: Err2: ClassTag,
+      Sub16 <: Err2: ClassTag,
+      Sub17 <: Err2: ClassTag,
+      Sub18 <: Err2: ClassTag,
+      Sub19 <: Err2: ClassTag,
+      Sub20 <: Err2: ClassTag,
+    ](
+      codec1: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub1],
+      codec2: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub2],
+      codec3: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub3],
+      codec4: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub4],
+      codec5: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub5],
+      codec6: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub6],
+      codec7: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub7],
+      codec8: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub8],
+      codec9: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub9],
+      codec10: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub10],
+      codec11: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub11],
+      codec12: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub12],
+      codec13: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub13],
+      codec14: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub14],
+      codec15: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub15],
+      codec16: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub16],
+      codec17: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub17],
+      codec18: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub18],
+      codec19: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub19],
+      codec20: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub20],
+    )(implicit alt: Alternator[Err2, Err]): Endpoint[PathInput, Input, alt.Out, Output, Auth] = {
+      val codec = HttpCodec.enumeration.f20(
+        codec1,
+        codec2,
+        codec3,
+        codec4,
+        codec5,
+        codec6,
+        codec7,
+        codec8,
+        codec9,
+        codec10,
+        codec11,
+        codec12,
+        codec13,
+        codec14,
+        codec15,
+        codec16,
+        codec17,
+        codec18,
+        codec19,
+        codec20,
+      )
+      self.copy[PathInput, Input, alt.Out, Output, Auth](error = codec | self.error)
+    }
+
+    def apply[
+      Sub1 <: Err2: ClassTag,
+      Sub2 <: Err2: ClassTag,
+      Sub3 <: Err2: ClassTag,
+      Sub4 <: Err2: ClassTag,
+      Sub5 <: Err2: ClassTag,
+      Sub6 <: Err2: ClassTag,
+      Sub7 <: Err2: ClassTag,
+      Sub8 <: Err2: ClassTag,
+      Sub9 <: Err2: ClassTag,
+      Sub10 <: Err2: ClassTag,
+      Sub11 <: Err2: ClassTag,
+      Sub12 <: Err2: ClassTag,
+      Sub13 <: Err2: ClassTag,
+      Sub14 <: Err2: ClassTag,
+      Sub15 <: Err2: ClassTag,
+      Sub16 <: Err2: ClassTag,
+      Sub17 <: Err2: ClassTag,
+      Sub18 <: Err2: ClassTag,
+      Sub19 <: Err2: ClassTag,
+      Sub20 <: Err2: ClassTag,
+      Sub21 <: Err2: ClassTag,
+    ](
+      codec1: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub1],
+      codec2: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub2],
+      codec3: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub3],
+      codec4: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub4],
+      codec5: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub5],
+      codec6: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub6],
+      codec7: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub7],
+      codec8: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub8],
+      codec9: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub9],
+      codec10: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub10],
+      codec11: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub11],
+      codec12: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub12],
+      codec13: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub13],
+      codec14: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub14],
+      codec15: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub15],
+      codec16: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub16],
+      codec17: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub17],
+      codec18: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub18],
+      codec19: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub19],
+      codec20: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub20],
+      codec21: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub21],
+    )(implicit alt: Alternator[Err2, Err]): Endpoint[PathInput, Input, alt.Out, Output, Auth] = {
+      val codec = HttpCodec.enumeration.f21(
+        codec1,
+        codec2,
+        codec3,
+        codec4,
+        codec5,
+        codec6,
+        codec7,
+        codec8,
+        codec9,
+        codec10,
+        codec11,
+        codec12,
+        codec13,
+        codec14,
+        codec15,
+        codec16,
+        codec17,
+        codec18,
+        codec19,
+        codec20,
+        codec21,
+      )
+      self.copy[PathInput, Input, alt.Out, Output, Auth](error = codec | self.error)
+    }
+
+    def apply[
+      Sub1 <: Err2: ClassTag,
+      Sub2 <: Err2: ClassTag,
+      Sub3 <: Err2: ClassTag,
+      Sub4 <: Err2: ClassTag,
+      Sub5 <: Err2: ClassTag,
+      Sub6 <: Err2: ClassTag,
+      Sub7 <: Err2: ClassTag,
+      Sub8 <: Err2: ClassTag,
+      Sub9 <: Err2: ClassTag,
+      Sub10 <: Err2: ClassTag,
+      Sub11 <: Err2: ClassTag,
+      Sub12 <: Err2: ClassTag,
+      Sub13 <: Err2: ClassTag,
+      Sub14 <: Err2: ClassTag,
+      Sub15 <: Err2: ClassTag,
+      Sub16 <: Err2: ClassTag,
+      Sub17 <: Err2: ClassTag,
+      Sub18 <: Err2: ClassTag,
+      Sub19 <: Err2: ClassTag,
+      Sub20 <: Err2: ClassTag,
+      Sub21 <: Err2: ClassTag,
+      Sub22 <: Err2: ClassTag,
+    ](
+      codec1: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub1],
+      codec2: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub2],
+      codec3: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub3],
+      codec4: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub4],
+      codec5: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub5],
+      codec6: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub6],
+      codec7: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub7],
+      codec8: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub8],
+      codec9: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub9],
+      codec10: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub10],
+      codec11: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub11],
+      codec12: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub12],
+      codec13: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub13],
+      codec14: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub14],
+      codec15: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub15],
+      codec16: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub16],
+      codec17: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub17],
+      codec18: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub18],
+      codec19: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub19],
+      codec20: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub20],
+      codec21: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub21],
+      codec22: HttpCodec[HttpCodecType.Status & HttpCodecType.Content, Sub22],
+    )(implicit alt: Alternator[Err2, Err]): Endpoint[PathInput, Input, alt.Out, Output, Auth] = {
+      val codec = HttpCodec.enumeration.f22(
+        codec1,
+        codec2,
+        codec3,
+        codec4,
+        codec5,
+        codec6,
+        codec7,
+        codec8,
+        codec9,
+        codec10,
+        codec11,
+        codec12,
+        codec13,
+        codec14,
+        codec15,
+        codec16,
+        codec17,
+        codec18,
+        codec19,
+        codec20,
+        codec21,
+        codec22,
+      )
+      self.copy[PathInput, Input, alt.Out, Output, Auth](error = codec | self.error)
+    }
+
   }
 
   private[endpoint] val defaultMediaTypes =
diff --git a/zio-http/shared/src/main/scala/zio/http/endpoint/openapi/JsonSchema.scala b/zio-http/shared/src/main/scala/zio/http/endpoint/openapi/JsonSchema.scala
index abd59326c0..d2063c2bc8 100644
--- a/zio-http/shared/src/main/scala/zio/http/endpoint/openapi/JsonSchema.scala
+++ b/zio-http/shared/src/main/scala/zio/http/endpoint/openapi/JsonSchema.scala
@@ -55,11 +55,11 @@ private[openapi] case class SerializableJsonSchema(
     if (nullable && schemaType.isDefined)
       copy(schemaType = Some(schemaType.get.add("null")))
     else if (nullable && oneOf.isDefined)
-      copy(oneOf = Some(oneOf.get :+ typeNull))
+      copy(oneOf = Some((oneOf.get :+ typeNull).distinct))
     else if (nullable && allOf.isDefined)
-      SerializableJsonSchema(allOf = Some(Chunk(this, typeNull)))
+      SerializableJsonSchema(allOf = Some((allOf.get :+ typeNull).distinct))
     else if (nullable && anyOf.isDefined)
-      copy(anyOf = Some(anyOf.get :+ typeNull))
+      copy(anyOf = Some((anyOf.get :+ typeNull).distinct))
     else if (nullable && ref.isDefined)
       SerializableJsonSchema(anyOf = Some(Chunk(typeNull, this)))
     else
@@ -117,8 +117,8 @@ private[openapi] object BoolOrSchema {
 private[openapi] sealed trait TypeOrTypes { self =>
   def add(value: String): TypeOrTypes =
     self match {
-      case TypeOrTypes.Type(string) => TypeOrTypes.Types(Chunk(string, value))
-      case TypeOrTypes.Types(chunk) => TypeOrTypes.Types(chunk :+ value)
+      case TypeOrTypes.Type(string) => TypeOrTypes.Types(Chunk(string, value).distinct)
+      case TypeOrTypes.Types(chunk) => TypeOrTypes.Types((chunk :+ value).distinct)
     }
 }
 
@@ -253,7 +253,7 @@ object JsonSchema {
       .toOption
       .get
 
-  private def fromSerializableSchema(schema: SerializableJsonSchema): JsonSchema = {
+  private[openapi] def fromSerializableSchema(schema: SerializableJsonSchema): JsonSchema = {
     val additionalProperties = schema.additionalProperties match {
       case Some(BoolOrSchema.BooleanWrapper(bool))  => Left(bool)
       case Some(BoolOrSchema.SchemaWrapper(schema)) =>
diff --git a/zio-http/shared/src/main/scala/zio/http/endpoint/openapi/OpenAPI.scala b/zio-http/shared/src/main/scala/zio/http/endpoint/openapi/OpenAPI.scala
index d9e57f5ef5..2dbf6f437e 100644
--- a/zio-http/shared/src/main/scala/zio/http/endpoint/openapi/OpenAPI.scala
+++ b/zio-http/shared/src/main/scala/zio/http/endpoint/openapi/OpenAPI.scala
@@ -97,15 +97,48 @@ final case class OpenAPI(
         .groupBy(_._1)
         .map { case (path, pathItems) =>
           val pathItem = pathItems.map(_._2).reduce { (i, j) =>
+            var docI    = Doc.empty
+            var docJ    = Doc.empty
+            var get     = i.get
+            var put     = i.put
+            var post    = i.post
+            var delete  = i.delete
+            var options = i.options
+            var head    = i.head
+            var patch   = i.patch
+            var trace   = i.trace
+
+            if (
+              get.isDefined || put.isDefined || post.isDefined || delete.isDefined || options.isDefined || head.isDefined || patch.isDefined || trace.isDefined
+            ) {
+              docI = i.description.getOrElse(Doc.empty)
+            }
+            if (
+              (get.isEmpty && j.get.isDefined) || (put.isEmpty && j.put.isDefined) || (post.isEmpty && j.post.isDefined) || (delete.isEmpty && j.delete.isDefined) || (options.isEmpty && j.options.isDefined) || (head.isEmpty && j.head.isDefined) || (patch.isEmpty && j.patch.isDefined) || (trace.isEmpty && j.trace.isDefined)
+            ) {
+              docJ = j.description.getOrElse(Doc.empty)
+            }
+            get = get.orElse(j.get)
+            put = put.orElse(j.put)
+            post = post.orElse(j.post)
+            delete = delete.orElse(j.delete)
+            options = options.orElse(j.options)
+            head = head.orElse(j.head)
+            patch = patch.orElse(j.patch)
+            trace = trace.orElse(j.trace)
+
             i.copy(
-              get = i.get.orElse(j.get),
-              put = i.put.orElse(j.put),
-              post = i.post.orElse(j.post),
-              delete = i.delete.orElse(j.delete),
-              options = i.options.orElse(j.options),
-              head = i.head.orElse(j.head),
-              patch = i.patch.orElse(j.patch),
-              trace = i.trace.orElse(j.trace),
+              get = get,
+              put = put,
+              post = post,
+              delete = delete,
+              options = options,
+              head = head,
+              patch = patch,
+              trace = trace,
+              description = Some(docI + docJ).filter(!_.isEmpty),
+              servers = i.servers ++ j.servers,
+              parameters = i.parameters ++ j.parameters,
             )
           }
           (path, pathItem)
diff --git a/zio-http/shared/src/main/scala/zio/http/endpoint/openapi/OpenAPIGen.scala b/zio-http/shared/src/main/scala/zio/http/endpoint/openapi/OpenAPIGen.scala
index 9b12066770..64ba057807 100644
--- a/zio-http/shared/src/main/scala/zio/http/endpoint/openapi/OpenAPIGen.scala
+++ b/zio-http/shared/src/main/scala/zio/http/endpoint/openapi/OpenAPIGen.scala
@@ -538,8 +538,7 @@ object OpenAPIGen {
       val path           = buildPath(endpoint.input)
       val method0        = method(inAtoms.method)
       // Endpoint has only one doc. But open api has a summery and a description
-      val pathItem       = OpenAPI.PathItem.empty
-        .copy(description = Some(endpoint.documentation + endpoint.input.doc.getOrElse(Doc.empty)).filter(!_.isEmpty))
+      val pathItem       = OpenAPI.PathItem.empty.copy(description = Some(endpoint.documentation).filter(!_.isEmpty))
       val pathItemWithOp = method0 match {
         case Method.OPTIONS => pathItem.addOptions(operation(endpoint))
         case Method.GET     => pathItem.addGet(operation(endpoint))
@@ -581,7 +580,7 @@ object OpenAPIGen {
     }
 
     def operation(endpoint: Endpoint[_, _, _, _, _]): OpenAPI.Operation = {
-      val maybeDoc = Some(endpoint.documentation + pathDoc).filter(!_.isEmpty)
+      val maybeDoc = Some(pathDoc).filter(!_.isEmpty)
       OpenAPI.Operation(
         tags = endpoint.tags,
         summary = None,
@@ -635,7 +634,7 @@ object OpenAPIGen {
 
     def queryParams: Set[OpenAPI.ReferenceOr[OpenAPI.Parameter]] = {
       inAtoms.query.collect {
-        case mc @ MetaCodec(HttpCodec.Query(HttpCodec.Query.QueryType.Primitive(name, codec), _), _)  =>
+        case mc @ MetaCodec(q @ HttpCodec.Query(HttpCodec.Query.QueryType.Primitive(name, codec), _), _) =>
           OpenAPI.ReferenceOr.Or(
             OpenAPI.Parameter.queryParameter(
               name = name,
@@ -648,10 +647,10 @@ object OpenAPIGen {
               examples = mc.examples.map { case (name, value) =>
                 name -> OpenAPI.ReferenceOr.Or(OpenAPI.Example(value = Json.Str(value.toString)))
               },
-              required = mc.required,
+              required = mc.required && !q.isOptional,
             ),
           ) :: Nil
-        case mc @ MetaCodec(HttpCodec.Query(record @ HttpCodec.Query.QueryType.Record(schema), _), _) =>
+        case mc @ MetaCodec(HttpCodec.Query(record @ HttpCodec.Query.QueryType.Record(schema), _), _)    =>
           val recordSchema = (schema match {
             case schema if schema.isInstanceOf[Schema.Optional[_]] => schema.asInstanceOf[Schema.Optional[_]].schema
             case _                                                 => schema
@@ -709,7 +708,7 @@ object OpenAPIGen {
               examples = mc.examples.map { case (exName, value) =>
                 exName -> OpenAPI.ReferenceOr.Or(OpenAPI.Example(value = Json.Str(value.toString)))
               },
-              required = !optional,
+              required = mc.required && !optional,
             ),
           ) :: Nil
       }
@@ -740,7 +739,8 @@ object OpenAPIGen {
             OpenAPI.Parameter.headerParameter(
               name = mc.name.getOrElse(codec.name),
               description = mc.docsOpt,
-              definition = Some(OpenAPI.ReferenceOr.Or(JsonSchema.fromTextCodec(codec.textCodec))),
+              definition =
+                Some(OpenAPI.ReferenceOr.Or(JsonSchema.fromTextCodec(codec.textCodec).nullable(!mc.required))),
               deprecated = mc.deprecated,
               examples = mc.examples.map { case (name, value) =>
                 name -> OpenAPI.ReferenceOr.Or(OpenAPI.Example(codec.textCodec.encode(value).toJsonAST.toOption.get))
@@ -940,9 +940,13 @@ object OpenAPIGen {
         case (mediaType, values)                                        =>
           val combinedAtomized: AtomizedMetaCodecs = values.map(_._1).reduce(_ ++ _)
           val combinedContentDoc                   = combinedAtomized.contentDocs.toCommonMark
+          val vals                                 =
+            if (values.forall(v => v._2.isNullable || v._2 == JsonSchema.Null))
+              values.map(_._2).filter(_ != JsonSchema.Null)
+            else values.map(_._2)
           val alternativesSchema                   = {
             JsonSchema
-              .AnyOfSchema(values.map { case (_, schema) =>
+              .AnyOfSchema(vals.map { schema =>
                 schema.description match {
                   case Some(value) => schema.description(value.replace(combinedContentDoc, ""))
                   case None        => schema
@@ -979,6 +983,10 @@ object OpenAPIGen {
         }
       case t: Transform[_, _, _]      =>
         nominal(t.schema, referenceType)
+      case Schema.Optional(inner, _)  =>
+        nominal(inner, referenceType)
+      case Schema.Lazy(schema0)       =>
+        nominal(schema0(), referenceType)
       case _                          => None
     }