Senior Software Engineer

Senior Software Engineer — Onshore

Onshore builds AI-native tax software. We automate the work that used to take CPAs weeks — R&D credits, 179D, cost seg, and more — using agents that do the analysis and humans who review it.

We're hiring a Senior Software Engineer to lead technical work across our stack and raise the bar for everyone around them.

What you'll do

• Architect and ship complex full-stack systems across our Vite + React frontend (shadcn, Tailwind) and SST backend (Bun, Lambda, AWS).
• Design and build AI-powered data pipelines and agent workflows that process client data end-to-end.
• Own major product surfaces from concept to production — make the hard technical calls and drive them through.
• Mentor engineers, lead code reviews, and shape engineering practices as we scale the team.
• Partner directly with founders, tax experts, and customers to turn ambiguous problems into shipped product.

You should have

• 5+ years building production software, with deep full-stack experience.
• Strong TypeScript and React; comfort architecting serverless systems on AWS.
• A track record of shipping non-trivial systems and pulling teammates up with you.
• Bias toward shipping, eye for craft, and high standards for the codebase.

Compensation

• $190K–$210K base
• $100K equity over 4 years (~0.045% of the company at our $220M valuation)
• Full benefits

NYC, in-office.