Document service worker usage.

README.md

@@ -29,6 +29,10 @@ babashka or Clojure JVM):
 
 See [doc/nrepl](doc/nrepl).
 
+### Service worker
+
+See [doc/serviceworker.md](doc/serviceworker.md).
+
 ## Tasks
 
 Run `bb tasks` to see all available tasks:

doc/serviceworker.md

@@ -0,0 +1,26 @@
+# Scittle in a service worker
+
+You can use Scittle to bootstrap a ClojureScript based service worker.
+
+Put the following code into e.g. `scittle-sw.js` to create a JavaScript based service worker, load Scittle, then fetch your script and eval it.
+
+```javascript
+importScripts("scittle.min.js");
+
+const request = await fetch("sw.cljs");
+const text = await request.text();
+const result = scittle.core.eval_string(text);
+```
+
+Then load `scittle-sw.js` in your HTML:
+
+```html
+<script>
+  if('serviceWorker' in navigator)
+    navigator.serviceWorker.register('scittle-sw.js');
+</script>
+```
+
+This will load `sw.cljs` and eval it in the context of the service worker.
+
+A ready-made example can be found at [chr15m/scittle-template-serviceworker](https://github.com/chr15m/scittle-template-serviceworker).