Rails Version Upgrader
Systematic Rails framework upgrades from 6.x to 7.x to 8.x. Automated deprecation fixes, Zeitwerk compatibility, and configuration migrations. One version at a time, fully tested.
The Upgrade That Never Happens
Your app is stuck on Rails 6.0. You know you need to upgrade. But every time it gets scheduled:
- "It's a 3-month project" — nobody wants to own a feature freeze
- "Last upgrade broke production" — the team still has PTSD
- "Too many deprecation warnings" — the backlog is overwhelming
- "Zeitwerk doesn't load our code" — autoloading mysteries
Meanwhile, you're missing security patches, performance improvements, and your developers can't use modern Rails features. The gap widens every month.
How the Agent Works
Version Path Analysis
Maps your upgrade path and identifies all blockers.
- → Detects current Rails version and gem constraints
- → Reads official Rails upgrade guides for each version jump
- → Identifies gems that need updates before Rails can upgrade
Deprecation Audit
Runs your test suite with deprecation warnings enabled.
- → Collects all deprecation warnings from tests
- → Categorizes by framework: ActiveRecord, ActionPack, ActiveJob
- → Generates fix plan with migration patterns for each deprecation
Configuration Migration
Updates all config files to match the new Rails version.
-
→
Updates
config.load_defaultsand environment files - → Handles removed/renamed configuration options
- → Migrates credentials, secrets, and initializers
Zeitwerk Compatibility
Fixes autoloading issues that break with the new loader.
- → Renames files to match constant names
- → Fixes namespacing issues and circular dependencies
- → Configures custom inflections and ignore paths
Framework Updates
Applies changes for each Rails component.
- → ActiveRecord: query interface, migration DSL, associations
- → ActionPack: routing changes, controller updates, form helpers
- → Asset pipeline: Webpacker to importmap/esbuild migration
Test & Validate
Runs the full suite and fixes any regressions.
- → Runs test suite after each major change
- → Identifies and fixes test failures caused by upgrade
- → Verifies boot time and critical paths work correctly
Clean Pull Request
Delivers a well-documented PR your team can review.
- → Atomic commits for each type of change
- → Links to Rails upgrade guides and changelogs
- → One version at a time. No giant leaps.
Safety Guarantees
One Version at a Time
Never skip versions. 6.0 → 6.1 → 7.0 → 7.1 → 7.2 → 8.0. Each step validated.
Deprecations First
All deprecation warnings fixed before attempting the version bump.
Test Suite Green
No PR is opened until the full test suite passes on the new version.
Official Guides
Every change references the official Rails upgrade documentation.
Atomic Commits
Each change type in its own commit. Easy to review, easy to revert.
Rollback Ready
Clear rollback instructions. One git revert undoes each version.
What This Is NOT
- ✗ Not a magic button. Complex apps need human judgment for edge cases. The agent handles 90%, I handle the rest.
- ✗ Not version skipping. You can't jump from 5.2 to 8.0. Each version has required steps.
- ✗ Not just Gemfile updates. Real upgrades require config changes, code fixes, and thorough testing.
- ✗ Not untested. Every change is verified against your test suite before delivery.
Typical Results
Stop Postponing Your Rails Upgrade
Start with a $1,500 audit. Get a full upgrade roadmap with timeline and risk assessment.