Senior Software Engineer

Headstart partners with digitally-native businesses ($100M+ ARR) to accelerate AI initiatives, enhance engineering capabilities, and drive real business outcomes. We build and ship production AI systems—from our innovative coding agent Friday (try us for free!) to custom agents and AI-powered features that solve the hardest technical problems.

Our engineers tackle the hardest problems with the latest technology, including our own innovative coding agent Friday. We are taking a different approach to innovation, one that has allowed us to push beyond what teams backed by multi-billion-dollar budgets are shipping today.
You'll work with frontier applied AI technologies across the stack—from foundational systems to user-facing applications. We're a lean, high-velocity team that ships directly to users, iterates rapidly, and measures success by real-world impact.
We believe that simplicity and engineering fundamentals are more important than ever in an AI-driven world. If you want to work on cutting-edge AI with real constraints, real users, and real impact, this is the place.

• Own and drive the full development lifecycle from ideation through production

• Prototype rapidly while ensuring long-term reliability, maintainability, and security

• Build intuitive, accessible full-stack products from frontend interfaces or internal tools that surface model workflows and automate complex processes

• Architect, build, and maintain scalable APIs and systems that integrate LLMs to power both internal tooling and customer-facing workflows

• Collaborate across teams to identify solutions to data-intensive problems

• Mentor and support the growth of other engineers while helping to define and drive the technical roadmap

• 5+ years of professional software engineering experience

• Strong interest in leveraging AI in the development lifecycle (bonus if experience)

• Enjoys a fast-paced and collaborative environment

• Proven track record owning full-stack systems: backend services (Python, FastAPI, Node.js), relational databases (Postgres/MySQL), and optionally frontend frameworks like React/Next.js

• Experience designing distributed systems, APIs, data pipelines, or developer productivity infrastructure at scale

• Bonus if you’ve been a founding engineer or startup early hire, with history building production products from scratch

• Bonus if you’re NYC based — we have a loft office in Soho and provide lunch and snacks

Note: Even if you don't meet all the requirements, we still encourage you to apply. This role offers extensive benefits, a base salary of $190,000 USD plus competitive equity compensation and 401k match. While this position is listed as hybrid in NYC or Toronto, we are open to considering fully remote candidates based in the US or Canada for the right fit.