Founding Full-Stack Engineer: Build AI-Native Infrastructure for Biopharma
At threesixfive, we’re partnering with a VC-backed startup redefining how biopharma companies plan, coordinate, and execute at scale.
This is a rare opportunity to join as a founding engineer and help build the technical foundations of AI-native workflows – systems where humans and AI agents collaborate seamlessly to drive faster, smarter decision-making in mission-critical industries.
You’ll work directly with deeply technical founders and early customers at leading biopharma companies to tackle hard problems at the intersection of distributed systems, knowledge graphs, and UX design.
With $2M+ in recent funding and a small, senior team moving fast, this role is ideal for engineers who want high ownership, technical depth, and impact.
What you’ll be doing
This is a true full-stack role with deep product ownership. You’ll work across the stack – from building primitives for data versioning and infrastructure to crafting clear, intuitive interfaces that surface complex, nonlinear workflows for users and AI agents alike.
Build backend foundations:
Architect versioned, auditable, high-throughput infrastructure to power advanced knowledge graphs.
Solve scaling, correctness, and complexity challenges – balancing read/write tradeoffs, consistency, and lineage tracking.
Invent intelligent UIs:
Design clear, ergonomic interfaces that blend structured workflows with natural language interaction.
Extend and refine the design system (Tailwind, Radix UI, shadcn/ui) with accessible, semantic components.
Collaborate and shape direction:
Work closely with founders, designers, and early biopharma customers to refine UX and deliver high-leverage tools for real users solving real problems.
Influence architecture and product strategy as part of a high-trust, low-ego team.
Why this role is different
This isn’t just another engineering job. The team is tackling foundational gaps in computer science – redefining database primitives and enabling AI-native systems of record. Starting with biopharma, they’re creating intelligent workflows where speed and accuracy directly impact human health.
About you
You’re a systems thinker and pragmatic builder who thrives in ambiguity and enjoys solving hard technical problems.
Hands-on experience designing and building data-intensive systems (PostgreSQL expertise a plus, especially with versioning, RLS, and concurrency control)
Proficiency across the stack: React, Next.js, TypeScript, Node.js, SQL, RPC
Strong bias toward shipping and iterating, even in uncertain environments
Deep curiosity and first-principles thinking
Clear communicator able to collaborate across technical and non-technical stakeholders
Bonus: Experience with Supabase, Inngest, Modal, Tailwind, Radix UI, shadcn/ui, Zod
Bonus: Background in high-output environments like startups, hedge funds, or mission-driven teams
This role could suit:
Unconventional thinkers building esoteric, technically challenging projects
Future founders seeking hands-on experience in a high-caliber early team
Ex-founders whose companies were acquired and want a mission-driven reset
Mission-oriented builders motivated by impact over career ladder
Why join?
Founding engineer impact: Shape architecture, culture, and product from day one
Deep technical challenges: Redefine knowledge infrastructure for the LLM era
Mission-driven work: Help accelerate breakthroughs in biopharma – where speed and precision save lives
High-caliber peers: Join a senior team obsessed with systems thinking and elegant design
Flexible setup: Remote-first within European time zones, with the option to relocate to Barcelona – a growing hub for biopharma and tech
The team’s core values
Low Ego – Strong opinions, weakly held; ideas over hierarchy
Ownership – Responsibility for outcomes, not just deliverables
Clarity – Making the complex understandable for users and teammates
First-principles thinking – Challenging assumptions, designing from the ground up
Velocity – Ship fast, learn faster, and ensure scalability
Mission-first – Relentless focus on empowering critical industries
About threesixfive
At threesixfive, we connect ambitious engineers with mission-driven companies solving hard problems. This opportunity is with one of our clients: a small, senior team building AI-native systems to transform critical industries like biopharma.
If you’re excited to build at the frontier of AI-native systems – and want high ownership in a high-trust, high-caliber team – we’d love to hear from you. Contact kris@threesixfive.es