diff --git a/README.md b/README.md
index 80ae0f97..be0e9703 100644
--- a/README.md
+++ b/README.md
@@ -64,14 +64,15 @@ If you want to use a simple `<script>` tag, the last release can be downloaded h
 
 Some npm scripts are available:
 
-| Command              | Description                                                                     |
-| -------------------- | ------------------------------------------------------------------------------- |
-| `npm install`        | install every dependency required for this project                              |
-| `npm run build`      | build a bundle of _owl_ in the _/dist/_ folder                                  |
-| `npm run minify`     | minify the prebuilt owl.js file                                                 |
-| `npm run test`       | run all tests                                                                   |
-| `npm run test:watch` | run all tests, and keep a watcher                                               |
-| `npm run extras`     | build extras applications, start a static server (see [here](extras/readme.md)) |
+| Command                | Description                                                                     |
+| ---------------------- | ------------------------------------------------------------------------------- |
+| `npm install`          | install every dependency required for this project                              |
+| `npm run build`        | build a bundle of _owl_ in the _/dist/_ folder                                  |
+| `npm run minify`       | minify the prebuilt owl.js file                                                 |
+| `npm run test`         | run all tests                                                                   |
+| `npm run test:watch`   | run all tests, and keep a watcher                                               |
+| `npm run extras`       | build extras applications, start a static server (see [here](extras/readme.md)) |
+| `npm run extras:watch` | same as `extras`, but with a watcher to rebuild owl                             |
 
 ## Documentation
 
diff --git a/extras/readme.md b/extras/readme.md
index 246d7304..b0d4729b 100644
--- a/extras/readme.md
+++ b/extras/readme.md
@@ -7,7 +7,7 @@ To help work/improve/learn with OWL, we have here:
 
 Both of them can be accessed by using a static http server.  A simple python
 server is available in `server.py`.  There is also a npm script to start it:
-`npm run extras`.
+`npm run extras` (and its version with a watcher: `npm run extras:watch`).
 
 ## Benchmarks
 
diff --git a/package.json b/package.json
index 66ed9ad3..96f3699b 100644
--- a/package.json
+++ b/package.json
@@ -5,16 +5,14 @@
   "main": "src/index.ts",
   "scripts": {
     "build:js": "tsc --target esnext --module es6 --outDir dist/owl src/*",
-    "build:js:es5": "tsc --target es5 --module es6 --outDir dist/owl src/*",
     "build:bundle": "rollup -c",
     "build": "npm run build:js && npm run build:bundle",
-    "build:es5": "npm run build:js:es5 && npm run build:bundle",
     "minify": "uglifyjs dist/owl.js -o dist/owl.min.js --compress --mangle",
-    "dev": "npm-run-all --parallel \"build:* -- --watch\"",
     "test": "jest",
     "test:watch": "jest --watch",
-    "preextras": "npm run build",
-    "extras": "python extras/server.py"
+    "extras:serve": "python extras/server.py",
+    "extras": "npm run build && npm run extras:serve",
+    "extras:watch": "npm-run-all  --parallel extras:serve \"build:* -- --watch\""
   },
   "repository": {
     "type": "git",