Senior Software Engineer

About Probook Probook is building AI infrastructure for the $700 billion home services industry. We have scaled 0-10M ARR in under 18 months while remaining cash-flow positive from day one, and are looking to not only be the fastest growing start‑up in the home services industry, but the fastest growing and most talent‑dense start‑up in NYC. The Opportunity This is not a role where you'll work on incremental features—you'll architect and ship the fundamental capabilities that define our platform. Every feature you build will directly impact ARR. You'll see your work drive customer adoption in real time, informed by direct customer feedback from our in‑person onboarding process. This is the ground floor of a category‑defining company. The systems you build in the next 12 months will scale to hundreds of millions in annual revenue. What You'll Do Build and deploy production AI systems that automate complex decision‑making for thousands of service businesses Ship features at a pace that would be quarterly initiatives at larger companies—expect weekend sprints Work directly with customers to understand their workflows and translate needs into technical solutions Integrate state‑of‑the‑art AI frameworks and tools into production systems Architect scalable backend infrastructure that supports rapid growth Own critical product features end‑to‑end, from design through deployment What We're Looking For Technical Excellence Exceptional coding fundamentals—comfortable with quant‑level technical problems while leveraging AI coding tools as force multipliers 2‑6 years of backend engineering experience, ideally at fast‑growing early‑stage startups or as a founding engineer Track record of building impressive systems or products (we actively evaluate for this in interviews) Ability to master an existing codebase and ship meaningful contributions within 48 hours Execution & Judgment Extreme bias for action—you ship fast without sacrificing quality Strong product sense and customer empathy—you understand what users need and how to deliver value Architectural judgment—you build robust, scalable systems, not fragile quick fixes Comfort with ambiguity and rapid context‑switching Mission Alignment Genuine passion for building software that impacts real working‑class Americans Energized by the trades and home services industry Willingness to engage directly with customers to understand their problems Who Thrives Here We're a high‑performance, in‑office team in NYC built around three core values: Blue Collar – We build software with real impact for people in the trades. We jump on customer calls, understand pain points deeply, and translate them into solutions that matter. 3‑Month Runway Mentality – We prioritize shipping speed and execution. We make thoughtful technical decisions but optimise for customer value today, not over‑engineered solutions tomorrow. Low Maintenance – We maintain a high engineering bar, hit our deadlines, and do whatever it takes to deliver for customers. We're on the same team, with zero politics. Every person at Probook is an A‑player with a track record of excellence in high‑stakes environments. We operate with intensity, hold ourselves to exceptionally high standards, and measure ourselves by outcomes. Why Now You're joining at the exact inflection point where: Product‑market fit is proven ($4M ARR in 9 months, 100% word‑of‑mouth growth) The technical foundation is still being built (your architecture decisions will matter for years) The team is small enough that you'll shape company culture and technical standards The opportunity is massive ($700B market, still mostly un‑automated) In 12 months, this role will exist, but won't be this role. Right now, you can still define everything. Benefits Competitive salary and meaningful equity Full medical, dental, and vision coverage Unlimited PTO 1K monthly stipend on Ramp #J-18808-Ljbffr