About this role
Builders is an AI-first venture studio in Rotterdam. We co-found enterprise AI companies from day zero. We built the platform that makes it work. It's called VSI. It's about to meet the world. We're hiring two Senior AI-First Engineers to join our Core Team. Same role, same level, same bar. Together you'll be the engineering backbone of VSI as it goes from production-with-beta-users to public platform. Two superstars, not two pairs of hands - each of you should be able to own most of the surface area on your own, and together you should be unstoppable. Why this role exists VSI is real. It's in production with our internal ventures, our ~10 beta founders, and is about to be opened up to the world. Outstanding offers with corporates are converting into signed pilots. Q2 launch is locked. The gap between here and there is engineering velocity. We need two senior, AI-native engineers who can ship VSI from prototype-grade to production-grade, and who can keep shipping at full speed once paying customers and corporates show up. We're hiring two together, deliberately. Engineering teams of one don't ship platforms; they ship features. Two senior engineers, working side-by-side, on the same codebase, with shared ownership of architecture and quality, is how this gets built. We want two people who could each, in a pinch, hold the whole system in their head - and who choose to work as a pair because together they ship twice as fast, not half as much each. What you'll build Ship VSI to the world VSI is a multi-agent platform that turns founder conversations into structured venture intelligence. Today: Radar, Sentinel, Orbit, and Beacon agents in production. Company memory ~80% built. Onboarding flow under construction. Public launch in Q2. Your job, day one: get VSI from "works for us" to "works for thousands." Production-grade core agents. Harden Radar, Sentinel, Orbit, and Beacon. Ship company memory v1 complete. Ship the onboarding flow that lets a founder sign up and self-serve their way to value. Multi-tenant architecture. Today's platform serves a handful of ventures. Q3's platform serves hundreds. You design and ship that scale-out - across our 3-tier RBAC model (devops / organisation / workspace), our Prisma + Supabase data layer, and our soft-delete and venture-isolation guarantees. Real-time agent orchestration. Conversation in → ingest → transcription → agent analysis → living-document updates → UI, all in seconds, all reliable, across many concurrent founders. We're collapsing our background pipeline onto Vercel (functions, queues, cron) and rebuilding ingest as a first-class surface; you'll own that migration end-to-end. API / MCP / CLI surfaces. Founders and their own agents need to plug into VSI. You build the surfaces that make that possible - including the MCP server that exposes ventures, conversations, signals, artifacts, speakers, and reflections to external agents. Ship continuously, not in milestones VSI doesn't have a "v1 then quarterly releases" cadence. It ships every week. You'll work in a daily standup rhythm, on a single board, with weekly Friday ship days where every person presents what they shipped and one Claude skill they built. Make the studio faster Every internal workflow we run sales, recruiting, founder onboarding, content production should be running on AI by default. You'll occasionally surface from VSI work to wire up new internal automations that compound the studio's velocity. Tech stack TypeScript end-to-end, with Python where the AI tooling demands it. The whole platform runs on Vercel and Supabase; Next.js and React on the front, Next.js API routes and background functions on the back, Postgres + pgvector for data and embeddings, Prisma as the ORM, Zod for validation, S3 for object storage. Anthropic, Gemini, and Assembly AI on the model side. Custom agent orchestration today; LangGraph or LangChain only where they earn their keep. We care about engineering judgement over specific stack experience. The right engineer picks up our exact tools in a week. Day one, you live in Claude Code or Cursor, daily, not occasionally.