If you’re trying to hire a Rails developer and you don’t have a technical background, you’re operating on faith. You’re reading resumes, trying to figure out what the buzzwords mean, and hoping the person you pick can actually deliver. That’s a rough position.
I’ve been on both sides of this — as the developer being evaluated, and as someone who’s helped clients figure out who they actually needed. Here’s what I’ve learned.
What a Rails Developer Actually Builds
“Rails developer” covers a wide range. At the core, it means someone who builds web applications using Ruby on Rails — a framework that handles the common patterns of web development so you can focus on the business-specific parts.
In practice, a Rails developer on a real project is:
- Building and maintaining database models that reflect your business domain
- Writing the business logic that handles what happens when a user does something
- Creating APIs that mobile apps or third-party services consume
- Integrating with external services — payment processors, shipping APIs, CRMs, ERPs
- Writing background jobs for things that shouldn’t happen synchronously (sending emails, processing files, syncing data)
- Maintaining and improving existing code without breaking what works
- Writing tests so changes don’t create regressions
The best Rails developers also think about architecture — not just “does this code work” but “will this decision make the next six months easier or harder.”
The Spectrum of Rails Experience
Not all Rails developers are equal. Here’s roughly how I’d describe the progression:
Junior (1-2 years): Knows the Rails conventions, can build CRUD features following established patterns, needs guidance on architecture and performance. Gets stuff done on well-defined tasks.
Mid-level (3-5 years): Comfortable with the full stack — can design database schemas, handle complex business logic, set up background jobs, optimize slow queries. Can work independently on most features.
Senior (5+ years): Has strong opinions about architecture and can back them up. Has made mistakes and learned from them. Can look at a codebase and quickly identify what’s going to cause problems. Can mentor other developers.
Expert/Principal (10+ years): Has seen enough production systems to have judgment that comes from pattern recognition, not just book knowledge. Can make architectural decisions with confidence and has the experience to know when to break the rules.
Most teams need a mix. Stacking a team entirely with juniors is a recipe for technical debt. Paying senior rates for every developer isn’t efficient for standard CRUD work.
What to Look For in a Good Rails Developer
They talk about trade-offs, not just tools. Good developers don’t just know what things are — they know when to use them. Ask about a decision they made and why. If they can’t articulate the trade-offs, that’s a signal.
They care about testing. This is almost diagnostic at this point. Developers who push back on testing or treat it as optional are developers who are leaving cleanup work for future developers (including their future selves).
They’ve maintained systems, not just built them. Building greenfield is different from maintaining something that’s been running for three years and has real users depending on it. Look for experience with legacy code, performance optimization, and careful migration work.
They understand the business problem, not just the technical one. The best Rails developers I’ve worked with ask “why” before they start writing code. Software that’s technically correct but solves the wrong problem is wasted effort.
They’re honest about what they don’t know. Nobody knows everything. Developers who pretend to know things they don’t are expensive to work with. The ones who say “I haven’t done that specific thing, but here’s how I’d approach learning it” are the honest ones.
Red Flags
Resume-driven development. Every new project uses the newest framework, the most cutting-edge tools. This is fine for personal projects, but in production software it means constant churn and upgrade risk. You want boring and reliable.
No tests in their sample code. If the code samples they share don’t have tests, that’s how they work. It’s a habit.
Vague about production experience. “I built a Rails app” is very different from “I’ve maintained a Rails app in production for three years with real users.” Probe this.
They can’t explain things simply. If they can’t explain what they built in terms a non-developer can follow, they’re not clear enough in their thinking to work well with the rest of your organization.
Hiring Freelance vs. Agency vs. Employee
For most businesses without a technical co-founder, the options are:
Freelance developer: Cheaper, flexible, but you’re dependent on one person. If they disappear or get busy, you’re stuck. Good for short-term projects.
Development agency: More expensive, but you get a team, continuity, and usually better process. Better for ongoing product development.
Employee: Best long-term if you have enough work to justify it. Requires technical management.
I run a development company that works somewhere between freelance and agency — small, focused, and built around solving your specific problem rather than filling seats. It’s the right fit for a lot of mid-market businesses.
If you’re trying to figure out what kind of Rails help you actually need, let’s talk. I’ll tell you honestly what makes sense for your situation, even if it’s not me.