Senior Software Engineer - Backend & Agent Platform

About Truewind Truewind (YC W23) is modernizing the financial back office — combining intelligent software with concierge service to automate bookkeeping, close, and financial reporting for startups and accounting firms. Our product is an AI agent that turns messy financial inputs into reviewed, posted accounting work. We're a small team putting real AI-native workflows in front of real accounting teams every day. The role We're hiring a senior backend engineer to help build and strengthen the platform behind our AI agent — the systems that run agent work reliably and connect it to customers' accounting tools. This is a backend- and systems-leaning role for someone who cares about building dependable infrastructure for an AI-native product, and who's energized by reliability and correctness, not just shipping screens. You'll join a small, high-ownership team where engineering sits close to the product. We work two-deep on every important system — no lone heroes, no undocumented black boxes — so you'll always have a partner, and we value people who document well and share what they know. Where you'll have impact We're intentionally not asking one person to carry everything. Depending on your strengths and interests, you'll grow into one or more of these areas over time, with a teammate alongside you:

• Backend services and APIs that power the product.
• Reliability and operations — helping our systems stay healthy and fast as we scale.
• Cloud infrastructure on AWS.
• Integrations with accounting platforms, where correctness really matters.

Your first 30 / 60 / 90 days

• 30 days: get deep in our backend, ship your first meaningful improvement, and start carrying a piece of our systems with a teammate.
• 60 days: take real ownership of a core service — including its reliability and on-call — and stand up the monitoring you'd want behind it.
• 90 days: own a meaningful slice of the platform end-to-end, and be the kind of second set of hands that makes the rest of the team faster.

You might be a great fit if you

• Have built and run backend services in production and care about keeping them reliable.
• Are strong in backend TypeScript/Node.
• Have worked with asynchronous, data-intensive, or distributed systems.
• Are comfortable with cloud infrastructure (AWS) and relational databases (PostgreSQL).
• Prefer simple, focused solutions over complexity, and communicate clearly.

Bonus points for any of

• Experience building with LLMs / AI agents in production.
• Fintech or accounting domain exposure (ERP integrations, an auditability mindset).
• A track record at early-stage companies and comfort with ambiguity.

Our stack TypeScript · Next.js · React · PostgreSQL · AWS — alongside modern AI tooling. Benefits Competitive salary and meaningful equity · health, dental, and vision insurance · twice-yearly off-sites in SF and NYC · a front-row seat on 0→1 AI product development.