diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index d89d43a9..93996800 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -30,13 +30,13 @@ jobs:
       - name: Run tests
         run: ./.tools/run_jvm_tests.sh
 
-  build-ts:
+  build-node:
     # prevent from running on forks
     if: github.repository_owner == 'restatedev'
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        node-version: [19.x]
+        node-version: [20.x]
 
     steps:
       - uses: actions/checkout@v3
@@ -50,6 +50,33 @@ jobs:
       - name: Run tests
         run: ./.tools/run_node_tests.sh
 
+  build-altjs:
+    # prevent from running on forks
+    if: github.repository_owner == 'restatedev'
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v3
+
+      # We just need npm from Node
+      - name: Setup Node
+        uses: actions/setup-node@v3
+        with:
+          node-version: 20.x
+
+      - name: Setup Bun
+        uses: oven-sh/setup-bun@v1
+        with:
+          bun-version: latest
+
+      - name: Setup Deno
+        uses: denoland/setup-deno@v1
+        with:
+          deno-version: v1.x
+
+      - name: Run tests
+        run: ./.tools/run_altjs_tests.sh
+
   build-go:
     # prevent from running on forks
     if: github.repository_owner == 'restatedev'
diff --git a/.tools/run_altjs_tests.sh b/.tools/run_altjs_tests.sh
new file mode 100755
index 00000000..c60e7494
--- /dev/null
+++ b/.tools/run_altjs_tests.sh
@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+
+set -eufx -o pipefail
+
+SELF_PATH=${BASH_SOURCE[0]:-"$(command -v -- "$0")"}
+PROJECT_ROOT="$(dirname "$SELF_PATH")/.."
+
+function bun_install_check() {
+    pushd $1
+    bun install
+    bun run build
+    popd
+}
+
+function deno_install_check() {
+    pushd $1
+    deno task build
+    popd
+}
+
+function wrangler_install_check() {
+    pushd $1
+    npm install
+    npm run build
+    npx wrangler deploy --dry-run --outdir dist
+    popd
+}
+
+wrangler_install_check $PROJECT_ROOT/templates/cloudflare-worker
+bun_install_check $PROJECT_ROOT/templates/bun
+deno_install_check $PROJECT_ROOT/templates/deno
diff --git a/.tools/run_node_tests.sh b/.tools/run_node_tests.sh
index a80a87ce..ab8246a7 100755
--- a/.tools/run_node_tests.sh
+++ b/.tools/run_node_tests.sh
@@ -14,7 +14,6 @@ npm_install_check $PROJECT_ROOT/basics/basics-typescript
 npm_install_check $PROJECT_ROOT/templates/typescript
 npm_install_check $PROJECT_ROOT/templates/typescript-lambda-cdk
 npm_install_check $PROJECT_ROOT/templates/cloudflare-worker
-#npm_install_check $PROJECT_ROOT/templates/bun
 
 npm_install_check $PROJECT_ROOT/templates/typescript-testing
 npm --prefix $PROJECT_ROOT/templates/typescript-testing run test
diff --git a/templates/bun/package.json b/templates/bun/package.json
index b63f44d0..fdf529dd 100644
--- a/templates/bun/package.json
+++ b/templates/bun/package.json
@@ -3,6 +3,7 @@
   "type": "module",
   "version": "0.0.1",
   "scripts": {
+    "build": "bun build --target bun --outdir dist src/index.ts",
     "dev": "bun run --watch src/index.ts",
     "start": "bun run src/index.ts",
     "format": "prettier --write \"src/*.+(js|ts|json)\""
diff --git a/templates/deno/deno.jsonc b/templates/deno/deno.jsonc
index 841d7663..1b6621e1 100644
--- a/templates/deno/deno.jsonc
+++ b/templates/deno/deno.jsonc
@@ -1,6 +1,7 @@
 {
   "tasks": {
+    "build": "deno check main.ts",
     "dev": "deno run --allow-net --allow-env --watch main.ts",
-    "start": "deno run --allow-net --allow-env main.ts"
-  }
+    "start": "deno run --allow-net --allow-env main.ts",
+  },
 }