Usually Cloudflare's Wrangler triggers a webpack build when a file is changed. This seems to be slow so I created this setup. Webpack builds to dist/index.js which triggers a restart of the worker when using wrangler dev from the dist folder.
This requires to have two terminal shells open. One for running npm run webpack-dev and another npm run wrangler-dev.
To test this you need to add dist/wrangler.toml with your own ids:
name = "test-webpack"
route = "example.com/*"
type = "javascript"
account_id = "XXXXXXXX"
zone_id= "XXXXXXX"
workers_dev = false