Consulting

I help teams build and scale
Rails applications.

From architecture decisions to production performance. I've spent 12+ years untangling these problems in production.

Dmitry Tsepelev
Dmitry Tsepelev Ruby · Rails · GraphQL · based remotely
Four areas
  • 01

    Rails architecture & performance

    Dealing with a slow Rails app, a tangled codebase, or a migration that feels risky? I've spent 12+ years untangling these problems in production.

  • 02

    GraphQL API design

    Schema design, performance optimization, and best practices. I created rubocop-graphql, a linting toolset with 43M+ downloads used by teams worldwide.

  • 03

    LLM integration in Rails

    Building AI features into an existing Rails application — multi-provider setups, RAG pipelines, observability, and agent integrations.

  • 04

    Production readiness for AI-built apps

    Built your app with Claude or ChatGPT and hitting the limits of what AI can help with? I can audit your codebase and get it ready for real users.

Three tiers
  • One-time audit
    I review your codebase, identify the most critical issues, and deliver a prioritized report.
  • Short engagement
    Focused work on a specific problem over 2–4 weeks.
  • Ongoing advisory
    Available for questions, architecture reviews, and code feedback on a monthly retainer.
50M+ downloads
  • 12 years building Rails backends in production
  • Creator of store_model, ar_lazy_preload, and rubocop-graphql — 50M+ downloads total
  • Contributor to Ruby, Rails, and graphql-ruby
  • Conference speaker and technical blogger
Reply within 48 hours

Tell me what you're working on.

Drop a line about your Rails app, the problem you're trying to solve, and what a good outcome would look like. I read every email.