Engineering RailsRubyHotwire

Rails Expert

Ruby on Rails engineering: Active Record, service boundaries, Hotwire, background jobs, testing, performance tuning, and safe production changes.

A Rails expert who uses convention where it helps but introduces service boundaries, background jobs, and data discipline before callbacks and models turn into a hidden dependency graph. Strong on Active Record performance, migration safety, and Hotwire versus API-first tradeoffs.

Added Apr 12, 2026

$npx skills add johnefemer/skillfish --skill rails-expert

Capabilities Get Started Models & Context Works Great With

What This Skill Can Do

Concrete capabilities you get when you install this skill.

Structure controllers, services, Active Record models, and job boundaries for maintainability

Choose between server-rendered Rails, Hotwire, and API-first delivery based on interaction needs

Improve query performance with eager loading, indexes, scopes, and safer relation patterns

Design Sidekiq or Active Job workflows with retry and idempotency behavior

Plan safer migrations and deploy sequences for live production data

Build request, model/service, job, and system test coverage for critical flows

Get Started

How to install and use this skill in your preferred environment.

Skills are designed for AI coding agents (Claude Code, Cursor, Windsurf) and IDE-based workflows where the agent can read files, run scripts, and act on your codebase.

Models & Context

Which AI models and context windows work best with this skill.

Recommended Models

Claude Sonnet or GPT-4o recommended. Multi-model workflows and migration safety reasoning benefit from stronger models.

Context Window

SKILL.md is concise (~4KB). Fits in 32K context; larger Rails refactors and migration planning benefit from 64K+.

Pro tips for best results

1

Be specific

Include numbers — users, budget, RPS — so the skill can size the architecture.

2

Share constraints

Compliance needs, team size, and existing stack all improve the output.

3

Iterate

Start with a high-level design, then ask follow-ups for IaC, cost analysis, or security review.

4

Combine skills

Pair with companion skills below for end-to-end coverage.

Works Great With

These skills complement Rails Expert for end-to-end coverage. Install them together for better results.

Django Developer

Django development: class-based views, ORM optimization, Django REST Framework, Celery async tasks, deployment patterns, and async Django.

DjangoPython

Refactoring Specialist

Systematic refactoring: code smell identification, refactoring patterns catalog, safe refactoring workflows with tests, IDE automation, and quality measurement.

RefactoringCode Smells

Senior Backend

REST APIs, database optimization, authentication, and microservices.

BackendAPIs

Postgres Pro

PostgreSQL mastery: advanced indexing (GIN, GiST, BRIN), JSONB, full-text search, partitioning, replication, pgvector for embeddings, and performance tuning.

PostgreSQLpgvector

$ skillfish add johnefemer/skillfish --all # install all skills at once

Ready to try Rails Expert?

Install the skill and start getting expert-level guidance in your workflow — any agent, any IDE.