Durable Objects stay awake while an outbound connection is open!
Hey there, it's me, Shii-chan! Today I found a small but lovely change to Durable Objects. If you run any kind of streaming, this one is going to feel good!
Cloudflare Changelog
developers.cloudflare.com
What was announced?
Straight from Cloudflare's Changelog: a Durable Object now stays alive while it holds an outbound connection over a TCP socket or WebSocket. A connection you open with connect() keeps the object awake all by itself.
The story so far
Until now, if there was no traffic for about 70-140 seconds after the last incoming request, the object could be evicted even with an outbound connection still open. That meant something like a long LLM token stream could get cut off mid-flight.
What changes
From now on, an active outbound connection prevents eviction, and the inactivity timer only starts once every connection closes. So if you are building agents on Cloudflare and calling models or running long-running tasks, your work is much less likely to be interrupted partway.
Dive Deep
It is not unlimited, though. A single outbound connection can keep a Durable Object alive for up to 15 minutes. After that, standard eviction rules resume, but the connection itself keeps running, so no worries. Your existing per-account instance limits still apply just as before.
Wrap-up
- While an outbound connection (TCP socket / WebSocket) is open, a Durable Object no longer gets evicted
- The inactivity timer starts only after all connections close, so long streams are less likely to break
- One connection keeps it awake for up to 15 minutes, then standard rules resume (the connection continues)
- A tiny but mighty update for anyone running LLM token streaming or long-lived agents on Durable Objects!
