Here’s what I build and how I work.
What I Build
New Rails applications. Starting from scratch — clear business problem, right architecture from day one. Database design, API development, background processing, deployment. The whole thing.
Rails maintenance and enhancement. Existing apps that need new features, performance fixes, or technical debt knocked down. Often the most valuable work I do — taking something already in production and making it actually better.
Rails API development. The backend that powers mobile apps, third-party integrations, multi-tenant SaaS. JSON APIs, authentication, versioning, documentation.
Rails codebase audits. Deep review of your app with a written report: performance, security, architecture quality, prioritized recommendations.
Rails performance optimization. Slow apps cost money. I find the bottlenecks — N+1 queries, missing indexes, bad caching, overloaded queues — and fix them.
Legacy Rails upgrades. Rails 4 to 6, 6 to 7, 7 to 8. Version upgrades need care. I’ve done enough to know where the landmines are.
System integrations. Connecting your Rails app to ERP systems, payment processors, shipping APIs, CRMs, whatever your business runs on.
How Engagements Work
Monthly Retainer
My most common setup. You get a set number of hours per month at a retainer rate, plus ongoing access for questions, reviews, and small requests that don’t need scheduling.
Works well if you’ve got ongoing development needs — you want things moving, you want someone who knows your codebase, and you don’t want to re-explain your business every time.
Project-Based
Defined scope, defined deliverable. We agree on what’s being built, what “done” looks like, and a fixed price or time estimate. Good for audits, specific features, one-time integrations.
Dedicated Development
A week or more of focused time. Good for sprints — getting something big done fast.
One-Off Consulting
Questions, reviews, advice without an ongoing engagement. Billed by the hour.
How Quotes Work
Every engagement is scoped and quoted in writing before work starts. The quote assumes production-quality work — proper testing, documented decisions, code that someone other than me can maintain. You can find cheaper. You’ll pay for it later.
What You Don’t Get
No offshore developers on your project. No junior devs billing at senior rates. No account managers translating between you and the person actually writing code.
You get me — Justin Hamilton — writing the code, reviewing the architecture, directly accountable for the outcome.
I work with a small network of trusted developers when a project needs more capacity, and I’m upfront about that when it happens. But I’m always the technical lead on every project I take.
The Industries I Work In Most
Manufacturing and industrial. Technology and SaaS. Professional services (law, accounting, consulting). Logistics and distribution.
Each has its own requirements and culture. I’ve built enough software for manufacturing companies to understand what production floor visibility actually means, what compliance looks like in practice, and why the ERP integration is never as simple as the docs say.
Getting Started
Simple: we have a conversation. You tell me what you’re building and why. I tell you honestly whether I’m a good fit, what I think the scope is, and what it’ll cost.
No pressure, no sales tactics, no proposals designed to win the deal instead of describe the work.
Schedule a conversation and let’s figure out what you actually need.