Senior Ruby On Rails Engineer Jobs in Arizona (NOW HIRING)

Soraban is building the AI that takes the manual work out of tax preparation. Our platform runs the entire workflow for accounting firms — client intake (Collect), data entry into their tax software (Connect), AI-native return prep (Prepare), and delivery with e-sign and payments (Deliver).

Here's how we move: our product engineers build the MVP, ~80% of the way there, validated against a clear roadmap. Your job is to take those MVPs to production: fast, and properly. Reliability, tests, scale, and the kind of UX polish that makes a skeptical CPA trust AI. This is the highest-leverage engineering work in the company. We need more builders who are great at it.

This is in-person 5x a week in Chandler, Arizona.

Not "product features." Real problems, this quarter:

• Production-harden MVPs across our four products against a roadmap that's already scoped — you'll rarely wonder what to build, the bar is how well and how fast.
• Make document pipelines reliable at scale — classification and extraction across W-2s, the 1099 series, multi-page K-1 packages, 1098s, 1095-As — feeding a human-in-the-loop review flow where accuracy is the product.
• Tame AI non-determinism — the hard, interesting part. Evals, regression tests, confidence/provenance on model outputs, and guardrails so a fallback or a truncated context never quietly ships a wrong return.
• Build backend systems that hold up — messy real-world PDFs, integrations with UltraTax, Lacerte, Drake, and CCH Axcess, and throughput that scales with the busy season.
• Earn CPA trust through small UX decisions — reviewers approve our AI's work side-by-side with the source documents. The interface either makes that fast and trustworthy or it doesn't.

• Week 1–2: Ship a real fix to production. Get deep on the codebase and the AI pipelines.
• By day 30: Own a slice of one product/project. Take an MVP feature from "works in the demo" to "works for every firm" — tests, edge cases, error states.
• By day 60: Lead the production-hardening of a roadmap feature end-to-end, and measurably improve the reliability of one AI extraction or review flow.
• By day 90: Own a product surface, ship meaningful improvements every week, and move a number that matters.

• Backend strength is non-negotiable. Data modeling, APIs, reliability, performance. Ruby on Rails is a plus, not a requirement — we care that you can build a solid backend, not which framework you've used.
• Product and UX judgment is non-negotiable. You feel it when a flow is clunky and you fix it without being asked. React / React Native experience is a plus; UX sense is the actual requirement.
• You're AI-native. You already build with AI tools every day. You know the best practices of AI-first development — when to let the model draft and when to take the wheel, and you never ship confident-sounding slop. AI-generated code gets tested and guardrailed, always.
• Low ego, team-first. You want the team to win. You'll happily spend a day hunting a bug because shipping something solid matters more than your line count. No heroes, no territory.
• Fast and careful at the same time. You move quickly against a clear roadmap and still build it properly. Both, not one.
• You're a builder. You've shipped things — ideally things that weren't assigned to you. Side projects with real users, a product you launched, a startup you started, substantial open-source work, indie-hacking revenue. If you build because you can't help it, you'll fit right in.

• You've built tax, accounting, or other financial software.
• You've worked directly with a founder before.
• You've started or shipped your own product — and you can show it.

We're looking for people who are running toward what we need — not just looking for the next role. The engineers who do their best work here chose Soraban deliberately: they want the pace, the ownership, the AI-first way we build, they love the intensity and hard work culture. If that's you, we should talk. We're currently receiving 100s of applications so help us identify you, tell us why you standout for this position.

• Skip the cover letter. Send links to what you've built — products, repos, case studies, demos. Show us, don't tell us.
• We're an onsite team in Tempe, AZ and San Francisco, CA, and we're excited about our new office. This role is in person.
• You must be legally authorized to work in the US. We're not able to offer visa sponsorship at this time.
• Principals only — no recruiters, please.