Build your own FaaS: Self-host workers, lambda, JavaScript functions

by giuseppelton 7/12/2023, 11:39 AMwith 5 comments

by jamesmcintyreon 7/12/2023, 6:03 PM

This is awesome! I'm working on a project that will heavily utilize FaaS and I've explored many options. Your combination of "secure and configure via workerd" with "autoscale and orchestrate with fly.io" is really great!

I know it's a POC but just some of my thought's / questions to see if you have any ideas or opinions on them:

- I briefly browsed workerd repo and it doesn't seem like there's an api to load a new worker script file to the existing workerd instance. Which is, i'm guessing, one reason why you're just restarting the whole fly machine to re-fetch the latest zipped resources at boot. - workerd repo mentions it's currently single-threaded - i'm wondering how fast workerd itself boots? - due to ^ those three points I'm wondering if a nice design would be: - publisher & worker use bullmq and it's sandbox-worker to spawn child process workers running workerd (helps utilize more threads & the bullmq worker code can take the job data input which contains the new user script to bootstrap config at job run). This would be good IF workerd boots fast.. - if workerd doesn't boot fast, and eventually you have many user scripts i can't see any other option than to have a third server that acts as a load-balancer/orchestrator. It would keep state of user scripts and which worker fly machines have told it it can run that script. Could still use a "buffer worker machine" which can "cold-boot" newly published scripts using the bullmq method i mentioned above.

Anyway, this is all really cool just wanted to spitball some ideas!

by giuseppelton 7/12/2023, 11:39 AM

Hi, this is more an experiment that a real production-tested project. You can create your own Function as a Service architecture, and self-host everywhere you want.

It leverages workerd, the Cloudflare worker runtime. And as deploy tutorial, it include a guide to host everything on Fly.

It support container-based deployment, so docker is your friend here.

The complete project is on: https://github.com/giuseppelt/self-workerd

Mind this a proof-of-concept, public exposed systems require more work.

by prakison 7/12/2023, 3:37 PM

This looks great.