Vercel "Build exceeded maximum duration" - Fix Slow Builds in CI
By Kaveh Alemi·Latchkey
Vercel cancelled the build because it ran past the maximum allowed duration. Either the build genuinely got slower, or a step hung - a watch task that never exits, or a stalled network fetch.
What this error means
The build is killed after a fixed window with The build exceeded the maximum allowed duration. A build that hung on a stuck step often passes on retry; a build that is simply too slow needs real optimization.
Vercel build log
Error: The build exceeded the maximum allowed duration. Your build was
automatically canceled.
Common causes
A hung or stuck build step
A dev/watch command left in the build, a process waiting on input, or a stalled network call can hang the build until it is force-cancelled. These are transient and often clear on retry.
Genuinely too-slow build
Large dependency installs with no cache, heavy asset processing, or building everything in a big monorepo can legitimately exceed the limit.
How to fix it
Ensure the build is non-interactive and exits
Make sure the Build Command is the production build (vite build), not a watch/dev server.
Run installs and tools in CI/non-interactive mode so nothing waits on input.
If a step hangs on a flaky fetch, retry the deploy - a hung fetch usually clears.
Speed the build up
Cut the work the build does: cache dependencies, build only what changed, and skip non-essential steps.
vercel.json
{
"buildCommand": "turbo run build --filter=web",
"installCommand": "npm ci"
}
How to prevent it
Keep the Build Command to the production build only; never a watch task.
Cache dependencies and use affected-only builds in monorepos.
Move heavy one-off processing out of the per-deploy build path.
Frequently asked questions
What causes ""exceeded maximum duration""?
A dev/watch command left in the build, a process waiting on input, or a stalled network call can hang the build until it is force-cancelled. These are transient and often clear on retry.
How do I fix "exceeded maximum duration"?
Ensure the build is non-interactive and exits
Can Latchkey fix this automatically?
Yes. Latchkey runs your GitHub Actions on managed runners that detect this failure, apply the fix, and retry the job automatically - self-healing is on by default.
