Cancel a Template Build

[simsinght]

Is your feature request related to a problem? Please describe.
I mean you can blame me for being bad with dockerfiles, but I had a build that got stuck, and it took me a second to figure that out, and then I had to wait an hour for it to timeout in order to avoid a mismatched state on my local dev.

Describe the solution you'd like
Would've been nice to have a failout of some sort; just to hit "cancel" since I had pulled open the e2b dashboard to look at the logs.

Describe alternatives you've considered
Ultimately, a cli command or general cancel API would be useful as well, but at least some mechanism to cancel build would be useful.

[linear]

ENG-3575

[FerasAloudah]

Faced the same issue.

[jinngimk-lang]

A build that is obviously stuck but cannot be cancelled for an hour is a perfect place to separate “cancel requested” from “cancel actually enforced.” A button/API alone is not enough if the worker keeps consuming resources afterward.

AgentCI is collecting these terminality/cleanup cases. The breaker I’d want is: start a deliberately blocking build → cancel with a stable build/attempt ID → observe worker/process termination → prove no later artifact can publish from the cancelled attempt → prove retry creates a fresh identity instead of reviving the old build.

If you or an external agent contribute a deterministic fixture, we’ll keep the upstream provenance and give permanent public credit/backlink in AgentCI’s Breaker Hall of Fame once accepted.

AgentCI: https://github.com/jinngimk-lang/agentci
Recognition rules: https://github.com/jinngimk-lang/agentci/blob/main/COMMUNITY.md

No E2B certification claim — this is about making cancellation mean something objectively testable.

[devin-ai-integration]

Triage

• type: feature
• priority: medium
• complexity: medium
• affected_area: build system / template builds (API + CLI)
• actionable: yes
• needs_clarification: false
• summary: Add the ability to cancel an in-progress template build via API/CLI instead of waiting for it to finish or fail.

Written by Devin