Staff Software Engineer - Experimentation

1 in 4 people in the US have a treatable mental health condition, but most providers don't accept insurance, making therapy too expensive for most people. Headway’s mission is to fix this by building a new mental healthcare system everyone can access. We started by solving the biggest barrier to care: insurance. The admin work - credentialing, claims, payment reconciliation - is a nightmare. We've automated that. But we're going further. Over 90,000 providers across all 50 states run their practice on our software, serving over 2.6 million patients. We are building the best tools for therapists to run their entire practice, reimagining the experience of finding a therapist, and investing in the platform foundations to enable this at scale, and building much of it with AI. We aren't just a billing layer; we are becoming the platform where care actually happens. We're a Series D company with $325M+ in funding (a16z, Accel, Spark Capital, etc.), looking for exceptional people to help us achieve this mission. We want your time here to be the most meaningful experience of your career. Join us, and help change mental healthcare for the better. About engineering at Headway Building a new mental healthcare system at Headway is only possible because of the scale and leverage that software can provide. The engineering team at Headway is a small but mighty team using technology to build that future (and have a fun time while doing it!). Principles that guide us: • Focus on the mission: We view software as a means of effecting change in the world, not as an end unto itself. We write software to empower our patients and therapists to better solve the problems they're facing. • Ship small, learn fast: We are building new and novel products and believe that we learn what our users need by quickly shipping and iteration • Everything is a product: Whether it's our patient search experience or a developer productivity improvement, we treat everything we build at Headway as a product with end-users in mind. • Optimize for trust: We believe that engineers should be continually learning. To learn effectively and to be productive, engineers must feel safe asking questions and discussing mistakes. Tools we use: • Languages: Python 3, TypeScript • Libraries & Frameworks: FastAPI, SQLAlchemy, React, Remix • Experimentation & Analytics: LaunchDarkly, Statsig, dbt, Snowflake • Datastores: Postgres, Redis • Infrastructure: AWS (Fargate, ECS, S3, and more), Cloudflare, Spark and Kafka • Monitoring: Datadog, PagerDuty, Sentry • Version Control: Github About the role We are looking for a Staff Software Engineer to own how Headway runs experiments. "Ship small, learn fast" is the second principle on the list above, and experimentation is how we actually do it: eleven teams have run hundreds of experiments deciding how patients find a therapist, how quickly new providers get up and running, whether our AI products are working, and how we collect the clinical outcomes data that proves care is effective. You will own the platform all of that runs on. This is a hands-on technical leadership role with unusually wide reach. You will design and build the core primitives, including how users are assigned to experiments, how we record what someone actually saw, and how we recognize the same person across devices and between browsing anonymously and signing in. You will decide what our long-term experimentation and feature flagging stack should be; we run LaunchDarkly and Statsig today, and that architecture is yours to evaluate and consolidate. You will also make AI a real part of the workflow, from validating an experiment's setup before it starts to catching a broken experiment automatically instead of discovering it in a Slack thread a week later.