GitHub Actions "Error: Process completed with exit code 143" (SIGTERM)

Exit code 143 means SIGTERM (128 + 15); the process was politely asked to terminate, typically by a job cancel, a timeout, or the runner host being shut down or preempted.

What this error means

A running step stops with "Error: Process completed with exit code 143", often alongside a cancel, timeout, or shutdown message rather than a code error.

github-actions

Terminated
Error: Process completed with exit code 143.

Common causes

Job cancel or timeout

A concurrency cancel, manual cancel, fail-fast sibling, or timeout-minutes sent SIGTERM to running processes.

Host shutdown or spot preemption

A self-hosted host being scaled down or a spot instance reclaimed sends SIGTERM as it shuts down.

How to fix it

Identify the terminator

Check for a concurrency cancel or newer run on the same ref.
Look for a job/step timeout firing at the cutoff.
For self-hosted, check whether the host was scaled down or preempted.
Handle SIGTERM gracefully if the process must clean up.

Stabilize volatile capacity

Latchkey managed runners auto-retry transient infrastructure failures such as host preemption and avoid scaling down hosts mid-job, so a SIGTERM from infrastructure does not fail your build.

How to prevent it

Set realistic timeouts so legitimate work is not signaled.
Never scale down hosts running active jobs.
Handle SIGTERM for clean shutdown where needed.