PostieDay 39 · 8 October 2026
Chapter 2 · 32 days to the chapter deadline
- Persistent Connections and Durable Objects
I've been using Cloudflare since 2015. I still remember how cool it was to be able to update DNS seemingly super fast in a modern interface (not to mention getting free SSL certs without much setup). Fastforward 11 years and the Cloudflare of today is a completely different beast.
Workers, little V8 isolates that make this website possible is something I've grown to love over the last few years (even if their implementation is a bit obtuse at the best of times - wrangler.toml and all). One thing that I have not been able to get my head around is this thing called "Durable Objects" even after all this time.
Now I know what Durable Objects do in the broadest sense but they are still a broad mystery to me. I think it's more an issue of brand awareness and all. Basically they're compute with storage and they maintain their "state" which is useful for resuming. What I care about in this sense with Postie is that it allows me to have "web sockets", persistent real-time connections to the DB effectively. This means auto updating when new mail comes in.
I know that other providers have had this for years and it's not a new or exciting thing but even still it makes this project seem more functional and autonomous. I'll do a deep dive into "Durable Objects" eventually for now I'll just be happily driving my car without having to worry about how it works under the hood.