diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2a9ef54d..8bb25eb7 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -55,6 +55,15 @@ jobs:
         if: matrix.java == 'temurin@17' && steps.setup-java-temurin-17.outputs.cache-hit == 'false'
         run: sbt +update
 
+      - name: Setup Node
+        if: matrix.project == 'rootJS'
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: npm
+
+      - run: npm ci
+
       - name: Check that workflows are up to date
         run: sbt githubWorkflowCheck
 
diff --git a/.gitignore b/.gitignore
index 82512572..bb115f94 100644
--- a/.gitignore
+++ b/.gitignore
@@ -13,8 +13,6 @@
 yarn.lock
 .tags*
 .java-version
-package.json
-package-lock.json
 metals.sbt
 .bloop/
 
@@ -70,7 +68,6 @@ smartgcal
 .jvmopts
 # Node modules
 node_modules/
-package-lock.json
 
 # Nix
 .direnv/
\ No newline at end of file
diff --git a/build.sbt b/build.sbt
index ff984554..69fe28c4 100644
--- a/build.sbt
+++ b/build.sbt
@@ -1,5 +1,3 @@
-import org.scalajs.linker.interface.OutputPatterns
-
 Global / onChangedBuildSource := ReloadOnSourceChanges
 
 ThisBuild / crossScalaVersions := List("3.6.2")
@@ -7,6 +5,16 @@ ThisBuild / tlBaseVersion      := "0.47"
 
 ThisBuild / tlCiReleaseBranches := Seq("master")
 
+ThisBuild / githubWorkflowBuildPreamble ++= Seq(
+  WorkflowStep.Use(
+    UseRef.Public("actions", "setup-node", "v4"),
+    name = Some("Setup Node"),
+    params = Map("node-version" -> "22", "cache" -> "npm"),
+    cond = Some("matrix.project == 'rootJS'")
+  ),
+  WorkflowStep.Run(List("npm ci"))
+)
+
 lazy val root = tlCrossRootProject.aggregate(core, testkit, tests)
 
 lazy val core = crossProject(JVMPlatform, JSPlatform)
@@ -55,26 +63,8 @@ lazy val tests = crossProject(JVMPlatform, JSPlatform)
     libraryDependencies ++= {
       Settings.Libraries.ScalaJSReactTest.value.map(_ % Test)
     },
-    // libraryDependencies ++= Seq(
-    //   ("org.webjars.npm" % "react"     % "18.3.1" % Test).intransitive(),
-    //   ("org.webjars.npm" % "react-dom" % "18.3.1" % Test).intransitive()
-    // ),
-    // jsEnv := new org.scalajs.jsenv.jsdomnodejs.JSDOMNodeJSEnv()
-    jsEnv := new org.scalajs.jsenv.jsdomnodejs.JSDOMNodeJSEnv(
-      org.scalajs.jsenv.jsdomnodejs.JSDOMNodeJSEnv
-        .Config()
-        .withEnv(
-          Map(
-            "NODE_PATH" -> (baseDirectory.value / "node_modules").absolutePath
-          )
-        )
-    ),
-    Test / scalaJSLinkerConfig ~= {
-      // Enable ECMAScript module output.
-      _.withModuleKind(ModuleKind.ESModule)
-        // Use .mjs extension.
-        .withOutputPatterns(OutputPatterns.fromJSFile("%s.mjs"))
-    }
+    jsEnv := new lucuma.LucumaJSDOMNodeJSEnv(),
+    scalaJSLinkerConfig ~= { _.withModuleKind(ModuleKind.CommonJSModule) }
   )
   // .jsSettings(
   //   Defaults.itSettings: _*
diff --git a/project/plugins.sbt b/project/plugins.sbt
index 4cbf87da..442f9127 100644
--- a/project/plugins.sbt
+++ b/project/plugins.sbt
@@ -1,3 +1,3 @@
 addSbtPlugin("edu.gemini" % "sbt-lucuma-lib" % "0.12.4")
 
-libraryDependencies += "org.scala-js" %% "scalajs-env-jsdom-nodejs" % "1.1.0"
+libraryDependencies += "edu.gemini" %% "lucuma-jsdom" % "0.12.4"