Service bindings - do I need to use waitUntil() in this scenario?

Suppose I have a service binding from worker A to worker B. Worker A is triggered over HTTP, and hands off to worker B to do a task e.g. update a DB record or call a remote API.

Worker A does NOT need to know the result of worker B's task - it simply kicks it off. Worker A is then free to terminate. In this scenario, do I need to use

waitUntil()

waitUntil()

in worker A or not? Struggling to understand when

waitUntil()

waitUntil()

is and is not required.

Thank you in advance.

MityaOP•1/30/25, 1:32 PM

Thank you. So this means that, without , worker B will shut down when worker A shuts down, is that right?

MityaOP•1/30/25, 1:32 PM

Thank you. (Cursor is giving me the opposite answer! AI, eh, what are you gonna do with it.)

MityaOP•1/30/25, 1:34 PM

If I use

waitUntil()

waitUntil()

, does worker B get its own fresh 30 seconds to run? Or must it operate within worker A's 30 seconds?

Mathis @ blaxel.ai•1/30/25, 6:39 PM

To add to the response, waitUntil is used to handle whatever action you want to take asynchronously and not needed to fullfill the request

Mathis @ blaxel.ai•1/30/25, 6:43 PM

If you call worker B in ctx.waitUntil, I'd assume it has to terminate before the workers A terminate (but it's not explicitly said in the documentation)

Mathis @ blaxel.ai•1/30/25, 6:43 PM

https://developers.cloudflare.com/workers/runtime-apis/context/#waituntil

Cloudflare Docs

Context (ctx) · Cloudflare Workers docs

The Context API in Cloudflare Workers, including waitUntil and passThroughOnException.

MityaOP•1/30/25, 6:54 PM

Thanks. Yeah I agree the docs are unclear on this. It says workers get 30 seconds (assuming a HTTP trigger) but it doesn't say whether workers invoked by service bindings must operate within that initial 30 seconds, or whether they get their own, fresh 30 seconds.