About TypeSafe

TypeSafe is a frontier model lab. We build reliable and general AI systems to power economically valuable automation. Our mission is to usher in a new era of Transformative Artificial Intelligence (TAI): technology with the power to drive a societal shift on the scale of the agricultural and industrial revolutions.

While others chase benchmarks and academic puzzles, we've been quietly rethinking the LLM stack from first principles — building a new kind of general frontier model designed for real-world reliability, decision-making, and autonomy in production.

We're a small, fast-moving team from OpenAI, Google Brain, and Meta/FAIR, backed by top-tier investors. Since mid-2024, we've been engineering the foundation for what comes after the current "state-of-the-art" — a model that actually gets things done.

About the role

As a senior backend engineer, you will join the team responsible for building and maintaining TypeSafe's API platform for inference. These APIs will be user facing, latency sensitive, and (once we ship) have uptime, reliability and backwards compatibility requirements. You'll be wearing many different hats and working across different levels in our inference system, with particular depth in distributed systems and networking. Responsibilities include:

• Define APIs for a new kind of AI inference experience and iterate on the design to ensure they are delightful to use

• Create robust infrastructure for serving inference across multiple cloud providers

• Define abstractions that will serve us moving forward as our billing needs and business logic needs grow

• Work on exposing new model features to users

Our tech stack is primarily Python. We also use TypeScript, Next.js, and Tailwind CSS for frontend, with Kubernetes for orchestration. We empower developers to use any tooling they find helpful for getting their job done, including Claude Code and Codex.

We expect that you

• Are responsible, ownership-inclined, and a team player – you believe there is no such thing as "other people's code", and will complain only the normal amount about pager duty

• Have experience designing storage abstractions for scaled backend systems

• Have experience designing resilient systems and improving on-call experience on production systems

• Collaborate well with others on technical and product design, advocating for what you need, and adjusting specs to changing requirements and feedback

• Are mission aligned and excited to go all-in

• Love being part of a team

We are hoping that you

• Have previously built big things

• Have 5+ years of professional software engineering experience (3+ years of infra/backend) with a team with rigorous engineering standards

• Have shipped backend services at scale with continuous delivery and uptime SLAs of at least 3 9s

• Have designed and operated a developer-facing API service

• Have experienced LLMs' capabilities and limitations from implementing them in the past

Life at TypeSafe

We're a small, flat, close-knit team dedicated to real-world impact preparing the world for Transformative AI. Our team works fully in-person in our San Francisco office near Embarcadero station. We love what we do and care about our work a lot.

We strive for excellence and craftsmanship and won't stop until we get there. When the team wins, we all win, and we enjoy collaborating and inspiring each other to grow as a team and as individuals.

We also value emotional honesty, kindness, and bringing your whole self to work. We build machines; we don't try to be machines.

We want you to be able to do the most impactful work of your career at TypeSafe and help define our future as a company.

We provide

• Base salary of $180k–280k plus equity, based on leveling

• 100% covered health insurance

• Daily lunch and dinner

• Visa sponsorships

• 401K plans