--- title: "Cancel superseded pull request runs" description: "Free runner capacity by canceling validation that a newer commit has replaced. Keep required main-branch and release runs intact." url: https://starsling.dev/ci-playbooks/techniques/cancel-superseded-runs canonicalUrl: https://starsling.dev/ci-playbooks/techniques/cancel-superseded-runs --- # Cancel superseded pull request runs Free runner capacity by canceling validation that a newer commit has replaced. Keep required main-branch and release runs intact. ## How it works Group validation runs by the pull request or branch they validate. When a newer commit starts another run in that group, cancel the older validation. Scope the cancellation rule to work that the new run replaces; deployment, release and migration workflows need their own completion rules. ## How to choose an approach Compare the examples by repository setup, prerequisites, and risks before adopting one. Each company implemented this in its own environment; measure each change against your own baseline. - **[Anthropic](https://starsling.dev/ci-playbooks/anthropic#cancel-superseded-runs)**: Use it when Developers or agents push to the same branch several times while CI is still running. Check before adopting: Deploy, publish and migration workflows keep running to completion; only runs whose result a newer commit replaces are cancelled. - **[Mastra](https://starsling.dev/ci-playbooks/mastra#cancel-superseded)**: Use it when Repeated pushes leave obsolete verification jobs occupying runners. Check before adopting: Key the group on workflow plus the logical PR or ref, with safe fallbacks, so a new commit cancels the old run. Keep release and destructive side-effect jobs out of indiscriminate cancellation. - **[Stripe](https://starsling.dev/ci-playbooks/stripe#cancel-only-obsolete-validation)**: Use it when Superseded pull request runs keep consuming runners. Check before adopting: Scope cancellation to replaceable pull request validation. Releases, deployments, migrations and default-branch runs that must finish keep cancel-in-progress off. - **[Uber](https://starsling.dev/ci-playbooks/uber#cancel-superseded-runs)**: Use it when Developers push several commits to a pull request in quick succession and each push starts a full run. Check before adopting: Key the group on the pull request so runs for different pull requests never cancel each other, and keep default-branch and release runs out of cancel-in-progress. ## Apply this technique ````text Evaluate and apply this CI technique to my repository: Cancel superseded pull request runs. Free runner capacity by canceling validation that a newer commit has replaced. Keep required main-branch and release runs intact. Read the technique and its source-backed company examples: https://starsling.dev/ci-playbooks/techniques/cancel-superseded-runs.md Inspect this repository’s CI workflows, build and test commands, dependencies, and recent run timings. Identify where this technique applies and explain the expected benefit using this repository’s evidence. Measure a baseline from recent comparable runs: elapsed time, queue time, runner minutes and failures where available. If data is unavailable, say what cannot be measured. Compare relevant company approaches, checking prerequisites, platform differences and tradeoffs. Rank applicable options by evidence, fit and measurable opportunity; do not present company results as predictions for this repo. Recommend the smallest safe change, show what checks and fallback paths remain, and ASK ME WHICH CHANGE TO APPROVE BEFORE EDITING ANY FILES. Only after approval, work on a new feature branch, make one reversible change, and open a reviewable pull request. Never merge or push to a default or protected branch. Keep required checks, test coverage, deployment and release behavior intact. Validate the change and compare equivalent runs where possible; report limitations and what should be monitored after merge. ```` ## How companies used this technique Read what each company changed and follow the original sources. ### Anthropic: Cancel superseded runs, never on main Anthropic's Python and TypeScript SDKs added a workflow concurrency group keyed on the branch, so a newer push cancels the older run. On main the group is keyed on the commit, so main runs never cancel each other. Evidence: Source PR/commit evidence Use it when: Developers or agents push to the same branch several times while CI is still running. Before applying it: Deploy, publish and migration workflows keep running to completion; only runs whose result a newer commit replaces are cancelled. [Read more in the Anthropic playbook](https://starsling.dev/ci-playbooks/anthropic#cancel-superseded-runs) [Primary source](https://github.com/anthropics/anthropic-sdk-python/commit/c8e75ece9e407966ed077a8e4e924e7ebd041c71) ### Mastra: Cancel obsolete runs using the correct event identity Mastra added workflow concurrency and cancellation to lint, docs and workspace workflows. Related changes handled workflow_run identity and separated comment-driven approval updates from PR updates. Evidence: Source PR/commit evidence Use it when: Repeated pushes leave obsolete verification jobs occupying runners. Before applying it: Key the group on workflow plus the logical PR or ref, with safe fallbacks, so a new commit cancels the old run. Keep release and destructive side-effect jobs out of indiscriminate cancellation. [Read more in the Mastra playbook](https://starsling.dev/ci-playbooks/mastra#cancel-superseded) [Primary source](https://github.com/mastra-ai/mastra/pull/14432) ### Stripe: Cancel superseded pull request runs Stripe iOS added a concurrency group to its dead-code workflow, keyed by pull request number, with cancel-in-progress so a new push stops the previous scan. Evidence: Source PR/commit evidence Use it when: Superseded pull request runs keep consuming runners. Before applying it: Scope cancellation to replaceable pull request validation. Releases, deployments, migrations and default-branch runs that must finish keep cancel-in-progress off. [Read more in the Stripe playbook](https://starsling.dev/ci-playbooks/stripe#cancel-only-obsolete-validation) [Primary source](https://github.com/stripe/stripe-ios/pull/7337) ### Uber: Cancel superseded pull request runs Base Web added a concurrency group keyed on the workflow and pull request number to its PR Check workflow, with cancel-in-progress, so a new push stops the run it supersedes. NilAway did the same for its Golden Test workflow. Evidence: Source PR/commit evidence Use it when: Developers push several commits to a pull request in quick succession and each push starts a full run. Before applying it: Key the group on the pull request so runs for different pull requests never cancel each other, and keep default-branch and release runs out of cancel-in-progress. [Read more in the Uber playbook](https://starsling.dev/ci-playbooks/uber#cancel-superseded-runs) [Primary source](https://github.com/uber/baseweb/pull/5407) ## CI optimization is continuous work. Apply this technique yourself, or use StarSling Runners for faster GitHub Actions and optional agent-driven optimization PRs, which teams on eligible paid plans can turn on. [Get self-improving CI](https://starsling.dev/products/runners) ## Related techniques ### [Run CI once per pull request commit](https://starsling.dev/ci-playbooks/techniques/run-ci-once) Remove overlapping push and pull request triggers so each change receives one intended validation run. 3 implementations · 3 companies (Anthropic, Shopify, Spotify) ### [Package once, and build full installers after merge](https://starsling.dev/ci-playbooks/techniques/package-once) Drop the build step that packaging repeats, and build the unpacked app pull requests test. 1 implementation · 1 company (DoorDash) ### [Reduce the setup floor before increasing shard count](https://starsling.dev/ci-playbooks/techniques/setup-cost-limits-sharding) Each extra shard repeats checkout, dependencies and container setup. 1 implementation · 1 company (Linear) ## Company Playbooks ### [Anthropic](https://starsling.dev/ci-playbooks/anthropic) Run only affected tests ### [DoorDash](https://starsling.dev/ci-playbooks/doordash) Run build and test in parallel, sharded across CI agents ### [Linear](https://starsling.dev/ci-playbooks/linear) Benchmark the same job on faster hardware ### [Mastra](https://starsling.dev/ci-playbooks/mastra) StarSling runners for the slowest test workflow ### [OpenAI](https://starsling.dev/ci-playbooks/openai) Rank CI fixes by the minutes they save ### [Ramp](https://starsling.dev/ci-playbooks/ramp) Move a CPU-bound test suite to a faster CPU ### [Shopify](https://starsling.dev/ci-playbooks/shopify) Let an agent iterate against one CI metric ### [Spotify](https://starsling.dev/ci-playbooks/spotify) Build arm64 on native arm64 runners ### [Stripe](https://starsling.dev/ci-playbooks/stripe) Run only the tests a change can reach ### [Uber](https://starsling.dev/ci-playbooks/uber) Build the merge-queue speculations most likely to be needed ## Related guides Implementation guides for this technique. ### [Cancel superseded CI runs](https://starsling.dev/best-practices/github-actions/cancel-superseded-runs) Use concurrency groups to keep PR verification focused on the latest commit. ### [Build and test only what changed](https://starsling.dev/best-practices/github-actions/build-only-affected) Scope work with your dependency graph and keep a full-run fallback. ### [Cut CI queue time](https://starsling.dev/best-practices/github-actions/cut-queue-time) Measure waiting time and identify concurrency or capacity constraints. ### [Filter workflows by changed files](https://starsling.dev/best-practices/github-actions/path-filter-workflows) Use paths and job conditions while keeping required checks reporting. ### [Bound runner jobs with timeouts](https://starsling.dev/best-practices/github-actions/bound-job-timeouts) Set job and step timeouts using expected durations and failure behavior. ### [Right-size GitHub Actions runners](https://starsling.dev/best-practices/github-actions/right-size-runners) Match runner resources to the workload and compare equivalent runs.