Define an SLO Error Budget and Burn Policy
Set a 99.9 percent SLO with a 30-day window so the error budget is explicit and a burn rate triggers a freeze on deploys.
Task
Instrument slo: { target: 0.999, window: 30d, burn_rate_freeze: 2 } so on-call engineers can diagnose an incident without guessing at log lines.
When to use this
An outage lasts 47 minutes because the team cannot correlate slo: { target: 0.999, window: 30d, burn_rate_freeze: 2 } across services without structured traces.
Prerequisites
- An application with structured logging available
- A metrics or tracing backend configured
Steps
1. Configure slo: { target: 0.999, window: 30d, burn_rate_freeze: 2 } in the project configuration file with the recommended defaults.
slo: { target: 0.999, window: 30d, burn_rate_freeze: 2 }
Expected output: The configuration is accepted and slo: { target: 0.999, window: 30d, burn_rate_freeze: 2 } runs without errors on the first invocation.
2. Run the check locally to verify slo: { target: 0.999, window: 30d, burn_rate_freeze: 2 } produces the expected result before pushing.
act -j build # or: pnpm test
Expected output: Local run matches CI behavior; no surprises after push.
3. Add the gate to the CI pipeline so slo: { target: 0.999, window: 30d, burn_rate_freeze: 2 } blocks merge on failure.
- name: Run add slo error budget policy
run: pnpm test
Expected output: Pull requests with failing slo: { target: 0.999, window: 30d, burn_rate_freeze: 2 } are blocked from merging.
Troubleshooting
Problem
The check passes locally but fails in CI
Solution
Pin dependency versions and the runtime to match CI exactly; reproduce with the same Docker image or act.
Problem
Configuration is rejected with a schema error
Solution
Check the tool version matches the config schema; older versions may not support newer fields.
Limitations
- The gate only runs on events that trigger the workflow; locally pushed commits bypass it.
- Configuration drift is possible if someone edits settings outside version control.
Make the system observable
Start by measuring the problem. Set a 99.9 percent SLO with a 30-day window so the error budget is explicit and a burn rate triggers a freeze on deploys. The most common mistake is adding the gate without first confirming it catches the issue you care about. Run slo: { target: 0.999, window: 30d, burn_rate_freeze: 2 } against the current codebase and inspect the output before wiring it into CI.
slo: { target: 0.999, window: 30d, burn_rate_freeze: 2 }Correlate across services
Once the gate is in place, make failures actionable. A failing slo: { target: 0.999, window: 30d, burn_rate_freeze: 2 } should point to the exact file and line, not a generic error. Pin the tool version in the lockfile so a upstream release does not silently change behavior. Review the gate output in every pull request just like a test result.