Dependency Upgrade Runbook

Overview

Outdated dependencies expose projects to security vulnerabilities, compatibility issues, and missing features. This runbook provides a repeatable process for upgrading dependencies safely with minimal risk.

When to Use

Use this resource when:

• A critical security patch is released for a direct or transitive dependency
• Major version upgrades are required for long-term support
• Quarterly or sprint-based maintenance windows for dependency refreshes

Solution

# Dependency Upgrade Runbook

## 1. Preparation

- [ ] Identify the dependency and target version
- [ ] Review the changelog / release notes for breaking changes
- [ ] Check open issues in the dependency repository for upgrade-related bugs
- [ ] Create a dedicated branch: `deps/upgrade-<name>-<version>`
- [ ] Ensure CI is green on the current main branch

## 2. Upgrade

- [ ] Update the version in `package.json`, `requirements.txt`, `pom.xml`, etc.
- [ ] Run the dependency installation command
- [ ] Check for peer dependency warnings or conflicts
- [ ] Run automated tests (unit, integration, lint)
- [ ] Run smoke tests against a local or staging environment

## 3. Validation

- [ ] Review test coverage reports for regressions
- [ ] Check application logs for new warnings or errors
- [ ] Verify critical user paths manually if behavior changed
- [ ] Run security scan (`npm audit`, `safety check`, OWASP dependency check)

## 4. Rollback Plan

- [ ] Tag the last known good commit before merge
- [ ] Document any manual data or config changes required
- [ ] Confirm rollback can be executed within 15 minutes

## 5. Merge & Monitor

- [ ] Open a pull request with changelog summary
- [ ] Deploy to staging and let it soak for 24 hours
- [ ] Deploy to production during low-traffic window
- [ ] Monitor error rates and latency for 48 hours post-deploy

Explanation

The runbook breaks upgrades into five phases to reduce risk. Preparation prevents surprises by reviewing changelogs. The Upgrade phase isolates changes in a branch. Validation uses automated and manual checks. The Rollback Plan ensures fast recovery. Merge & Monitor completes the cycle with production observation.

Variants

Context	Approach	Notes
Security patch	Fast-track branch	Skip soak time only for CVEs with active exploits
Major version	Feature-flag rollout	Isolate new behavior behind flags during transition
Monorepo	Batch upgrades	Upgrade shared libs first, then consumers

Best Practices

1. Upgrade one major dependency at a time to simplify debugging
2. Pin exact versions in lock files (package-lock.json, poetry.lock) and commit them
3. Use automated tools like Dependabot or Renovate for patch and minor upgrades
4. Maintain a deprecation calendar for end-of-life dependencies
5. Document all breaking changes and migration steps in the pull request

Common Mistakes

1. Upgrading multiple major dependencies simultaneously, making failures hard to attribute
2. Ignoring peer dependency warnings that cause runtime errors
3. Skipping the rollback plan, extending downtime when issues surface
4. Not reviewing transitive dependency changes in lock files
5. Deploying during peak traffic without a soak period

Frequently Asked Questions

How often should I upgrade dependencies?

Patch versions: weekly or automated. Minor versions: monthly. Major versions: quarterly or when required.

What if a transitive dependency has a CVE?

Use npm audit fix, pip-audit, or override/resolution fields to force a patched transitive version without waiting for the direct dependency.

Should I commit lock files?

Yes. Lock files ensure reproducible builds across environments and make diffs reviewable during upgrades.