diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index eb0c6972..45e5fa9b 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -26,4 +26,11 @@ jobs:
 
       - run: spago build
 
-      - run: spago test --no-install
\ No newline at end of file
+      - run: spago test --no-install
+
+      - name: Use Node.js 
+        uses: actions/setup-node@v1
+        with:
+          node-version: 12.x
+
+      - run: node ./run-example-tests.js
diff --git a/examples/1-simple/package-lock.json b/examples/1-simple/package-lock.json
new file mode 100644
index 00000000..1842a9e9
--- /dev/null
+++ b/examples/1-simple/package-lock.json
@@ -0,0 +1,450 @@
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+  "name": "1-simple",
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+        "mime-types": "~2.1.24",
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+        }
+      }
+    },
+    "serve-static": {
+      "version": "1.14.1",
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+      "integrity": "sha512-JMrvUwE54emCYWlTI+hGrGv5I8dEwmco/00EvkzIIsR7MqrHonbD9pO2MOfFnpFntl7ecpZs+3mW+XbQZu9QCg==",
+      "requires": {
+        "encodeurl": "~1.0.2",
+        "escape-html": "~1.0.3",
+        "parseurl": "~1.3.3",
+        "send": "0.17.1"
+      }
+    },
+    "setprototypeof": {
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/setprototypeof/-/setprototypeof-1.1.1.tgz",
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+    },
+    "statuses": {
+      "version": "1.5.0",
+      "resolved": "https://registry.npmjs.org/statuses/-/statuses-1.5.0.tgz",
+      "integrity": "sha1-Fhx9rBd2Wf2YEfQ3cfqZOBR4Yow="
+    },
+    "toidentifier": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/toidentifier/-/toidentifier-1.0.0.tgz",
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+    },
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+      "version": "1.6.18",
+      "resolved": "https://registry.npmjs.org/type-is/-/type-is-1.6.18.tgz",
+      "integrity": "sha512-TkRKr9sUTxEH8MdfuCSP7VizJyzRNMjj2J2do2Jr3Kym598JVdEksuzPQCnlFPW4ky9Q+iA+ma9BGm06XQBy8g==",
+      "requires": {
+        "media-typer": "0.3.0",
+        "mime-types": "~2.1.24"
+      }
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+      "integrity": "sha1-sr9O6FFKrmFltIF4KdIbLvSZBOw="
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+      "integrity": "sha1-n5VxD1CiZ5R7LMwSR0HBAoQn5xM="
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+      "resolved": "https://registry.npmjs.org/vary/-/vary-1.1.2.tgz",
+      "integrity": "sha1-IpnwLG3tMNSllhsLn3RSShj2NPw="
+    },
+    "xhr2": {
+      "version": "0.2.0",
+      "resolved": "https://registry.npmjs.org/xhr2/-/xhr2-0.2.0.tgz",
+      "integrity": "sha512-BDtiD0i2iKPK/S8OAZfpk6tyzEDnKKSjxWHcMBVmh+LuqJ8A32qXTyOx+TVOg2dKvq6zGBq2sgKPkEeRs1qTRA==",
+      "dev": true
+    }
+  }
+}
diff --git a/examples/1-simple/package.json b/examples/1-simple/package.json
new file mode 100644
index 00000000..eb98c0e0
--- /dev/null
+++ b/examples/1-simple/package.json
@@ -0,0 +1,21 @@
+{
+  "name": "1-simple",
+  "version": "1.0.0",
+  "description": "",
+  "main": "server.js",
+  "directories": {
+    "test": "test"
+  },
+  "scripts": {
+    "test": "npm i && spago build && node ./test.js",
+    "start": "node server.js"
+  },
+  "author": "",
+  "license": "ISC",
+  "dependencies": {
+    "express": "^4.17.1",
+    "express-graphql": "^0.12.0",
+    "graphql": "^15.4.0",
+    "xhr2": "^0.2.0"
+  }
+}
diff --git a/examples/1-simple/server-fn.js b/examples/1-simple/server-fn.js
new file mode 100644
index 00000000..aa885290
--- /dev/null
+++ b/examples/1-simple/server-fn.js
@@ -0,0 +1,45 @@
+
+
+module.exports = (onListening) => {
+    const express = require('express')
+    const { graphqlHTTP } = require('express-graphql')
+    const { buildSchema } = require('graphql')
+    
+    const schema = buildSchema(`
+    type Query {
+        prop: String
+        widgets(id: Int): [Widget]
+    }
+    
+    type Widget { 
+        id: Int
+        name: String
+    }
+    `)
+    
+    const root = {
+      prop: () => {
+        return 'Hello world!'
+      },
+      widgets: ({ id }) =>
+        widgets.filter(w => !id || id === w.id)
+    
+    }
+    
+    const widgets = [
+      { id: 1, name: 'one' },
+      { id: 2, name: 'two' }
+    ]
+    
+    const app = express()
+    
+    app.use('/graphql', graphqlHTTP({
+      schema,
+      rootValue: root,
+      graphiql: true
+    }))
+
+    app.listen(4000, onListening)
+
+    console.info('Running a GraphQL API server at http://localhost:4000/graphql')    
+}
diff --git a/examples/1-simple/server.js b/examples/1-simple/server.js
index e5944862..e1ed5636 100644
--- a/examples/1-simple/server.js
+++ b/examples/1-simple/server.js
@@ -1,39 +1 @@
-const express = require('express')
-const { graphqlHTTP } = require('express-graphql')
-const { buildSchema } = require('graphql')
-
-const schema = buildSchema(`
-type Query {
-    prop: String
-    widgets(id: Int): [Widget]
-}
-
-type Widget { 
-    id: Int
-    name: String
-}
-`)
-
-const root = {
-  prop: () => {
-    return 'Hello world!'
-  },
-  widgets: ({ id }) =>
-    widgets.filter(w => !id || id === w.id)
-
-}
-
-const widgets = [
-  { id: 1, name: 'one' },
-  { id: 2, name: 'two' }
-]
-
-const app = express()
-
-app.use('/graphql', graphqlHTTP({
-  schema,
-  rootValue: root,
-  graphiql: true
-}))
-app.listen(4000)
-console.log('Running a GraphQL API server at http://localhost:4000/graphql')
+require('./server-fn')()
\ No newline at end of file
diff --git a/examples/1-simple/spago.dhall b/examples/1-simple/spago.dhall
index 91a9578f..63460cf8 100644
--- a/examples/1-simple/spago.dhall
+++ b/examples/1-simple/spago.dhall
@@ -22,7 +22,6 @@ You can edit this file as you like.
   , "spec-discovery"
   , "strings"
   , "strings-extra"
-  , "substitute"
   , "typelevel"
   , "variant"
   ]
diff --git a/examples/1-simple/test.js b/examples/1-simple/test.js
new file mode 100644
index 00000000..63c0192a
--- /dev/null
+++ b/examples/1-simple/test.js
@@ -0,0 +1,14 @@
+const { deepStrictEqual } = require('assert')
+const logs = [];
+
+console.log = (log) => {
+    logs.push(log);
+};
+
+require('./server-fn')(require('./output/Main').main)
+
+setTimeout(() => {
+    deepStrictEqual(logs, ['["one"]'])
+    console.info('tests passed')
+    process.exit(0)
+}, 250)
\ No newline at end of file
diff --git a/run-example-tests.js b/run-example-tests.js
new file mode 100644
index 00000000..5af778df
--- /dev/null
+++ b/run-example-tests.js
@@ -0,0 +1 @@
+console.log('hello e2e')
\ No newline at end of file