Deployment Checklist

Ensure code is production-ready before deploying. This skill runs through a structured verification process that catches common deployment failures before they reach users.

⛔ The Iron Law

Don't check a box you haven't verified.

Every checked item is backed by evidence — a command you ran in this session or code you read — not memory or assumption. "Should be fine" is not a verification. A blocked deploy is far cheaper than a production incident, so when a gate fails, stop and fix it before proceeding.

Workflow

Step 1: Assess the Change

Understand the scope and risk of what's being deployed:

• What changed? Review the diff against the deployment target branch
• Change type? Feature / bugfix / hotfix / infrastructure / dependency update
• Risk level? Low (cosmetic), Medium (logic change), High (data migration, auth, payments)
• Rollback plan? Can this be reverted with a simple deploy, or does it require data migration reversal?

Step 2: Run the Checklist

Walk through each section. Check items by reading code, running commands, and verifying artifacts.

Code Quality

• All tests pass (npm test, pytest, or project-specific command)
• No linting errors or warnings
• No TODO or FIXME items related to this change left unaddressed
• No debugging code (console.log, debugger, print statements) left in
• No commented-out code blocks

Testing

• New behavior has corresponding tests
• Edge cases and error paths are tested
• Integration tests pass against a clean environment
• If applicable: manual testing completed on staging

Security

• No hardcoded secrets, API keys, or credentials
• No new endpoints without authentication/authorization
• User input is validated and sanitized
• Dependencies have no known critical vulnerabilities (npm audit, pip audit)

Database & Data

• Migrations are forwards-compatible (old code works with new schema)
• Migrations are reversible
• Large data changes have been tested on production-sized data
• No destructive operations without confirmation (DROP, DELETE without WHERE)
• Backfill scripts are idempotent (safe to run multiple times)

This checklist verifies a migration; it does not design one. When a box above fails — a rename with no forwards-compatible path, an irreversible migration, a change that cannot be split across deploys — the answer is an expand-contract migration strategy, and that is data-modeling's work. Say so rather than green-lighting a redesign from the checklist.

Configuration & Environment

• New environment variables are documented and set in all target environments
• Feature flags are in the correct state for this release
• No environment-specific hardcoding (localhost URLs, test credentials)

Observability

• Errors are logged with sufficient context for debugging
• New endpoints/operations have appropriate metrics or monitoring
• Alert thresholds are reviewed for new functionality

Documentation

• README updated if setup steps changed
• API documentation updated for new/changed endpoints
• Release cut correctly, if this deploy ships one — version, changelog, tag consistent (see release-management)
• Breaking changes are clearly communicated

Step 3: Report

Summarize the checklist results:

• Ready to deploy: All checks pass
• Needs attention: List specific items that need fixing
• Blocked: Critical issues that must be resolved (data loss risk, security gap, failing tests)

Step 4: Deploy Safely

Based on the change risk level:

• Low risk: Deploy directly, monitor for 15 minutes
• Medium risk: Deploy to staging first, verify, then production. Monitor for 1 hour
• High risk: Deploy behind a feature flag, canary to a small percentage, monitor, then roll out gradually

Quick Reference

For urgent hotfixes where the full checklist feels heavy, run at minimum:

1. Tests pass
2. No secrets in code
3. Migrations are reversible
4. Rollback plan exists

Everything else can be addressed in a follow-up, but these four prevent the worst outcomes.

Principles Applied

• KISS: The simplest deploy that can safely reach production. Avoid adding complexity (new flags, new services) in the same deployment as the feature.
• Defense in depth: Validate at every gate — tests, staging, canary — not just once. Each gate catches a different class of failure.
• Fail fast: If a check fails, stop and fix before proceeding. A blocked deploy is far cheaper than a production incident.
• YAGNI: Don't deploy speculative configuration or unused feature flags. Unused config is future confusion.

See references/pre-deploy-gates.md for environment-specific checklists, schema migration safety, and rollback trigger criteria.

Rationalizations to reject

Red flags — stop and correct course

• Marking items complete from memory rather than checking.
• "Should be fine" / "probably works" language about any gate.
• Deploying a High-risk change with no rollback plan.
• Bundling a risky migration and a feature in the same deploy.

Cross-Skill References

• data-modeling — name this handoff whenever a migration fails a Database & Data box. This skill decides whether a migration is safe to ship; that one designs the expand-contract sequence (add, backfill, dual-write, cut over, drop) that makes it safe.
• release-management — cutting the versioned release (semver, changelog, tag, publish) that this checklist deploys
• rollback-strategy — design the rollback plan before deploying (required for High-risk changes)
• configuration-strategy — verify all environment variables and feature flags are configured correctly
• incident-response — use if the deployment causes a production incident
• verification-before-completion — the evidence gate behind every checked box