// use case

Expose your FastAPI dev server to Twilio for Twilio webhooks

1. 1

   Reserve a stable subdomain

   On the lrok free plan you keep one reserved subdomain forever. Pick a name your Twilio dashboard can hold onto — webhook URLs that survive laptop restarts mean fewer dashboard re-pastes.

   $ lrok reserve fas-twilio
     Reserved https://fas-twilio.lrok.io

2. 2

   Run your FastAPI app

   Start the dev server on port 8000 (the FastAPI default).

   $ uvicorn main:app --reload

3. 3

   Tunnel localhost to the public URL

   lrok forwards https://fas-twilio.lrok.io/webhook → http://127.0.0.1:8000/webhook. The flag --hint binds your reserved subdomain to this tunnel.

   $ lrok http 8000 --hint fas-twilio
     Forwarding https://fas-twilio.lrok.io  ->  http://127.0.0.1:8000

4. 4

   Paste the URL into Twilio

   Phone Numbers → Active Numbers → Messaging webhook. Paste https://fas-twilio.lrok.io/webhook as the destination.

5. 5

   Watch deliveries land in the request inspector

   Every webhook Twilio sends shows up at lrok.io/dashboard with full body, headers, status, and latency. Re-deliver any request to your FastAPI handler with one click. Twilio expects a TwiML response (XML). Return Content-Type: application/xml with <Response><Message>...</Message></Response>. The inspector shows what Twilio actually parsed.