Fullstack Engineer - Cofounder
Full-time
The General Intelligence Company Of New York
About Cofounder
Cofounder is an autonomous agent platform that connects to your tools (Gmail, Slack, Notion, Linear, Google Workspace, GitHub, Airtable, etc.) to run workflows end to end. We’re building the operating system for one-person, billion-dollar companies.
What you’ll own
End-to-end product work across the agent experience: flows, integrations, and UI/UX
Flows: creation, editing, run criteria, execution reliability, and observability
Integrations: add new integrations and deepen existing ones
UI/UX: work on novel, interesting ways of building human <> agent interactions
Product sense for complex UX: making powerful systems feel simple and reliable
Ship features across the stack with a tight feedback loop from real users (frontend + backend)
Improve performance, reliability, and cost across agent runs and flow execution
Build instrumentation, analytics, and developer tooling to speed up iteration
Maintain a high bar for code quality, tests, observability, and documentation
Requirements
4+ years building and shipping user-facing products end to end
Frontend: React/Next.js (or equivalent), TypeScript; component-driven development, performance profiling, accessibility, data fetching/state, optimistic UI and cache invalidation
Backend: Python FastAPI, background workers/queues, webhooks, Postgres (or similar) schema design, transactions, migrations
Solid testing and observability habits (unit/integration tests, metrics, traces, structured logs)
Bias to ship: scope thin slices, deliver quickly, instrument, iterate
Nice to have
Event-driven architectures (Inngest/Temporal), WebSockets/real-time UIs
LLM/agent experience: tool-use patterns, prompt hygiene, guardrails, evaluation
Infra familiarity (Render/Modal/Supabase/Redis Cloud or equivalent), CI/CD, feature flags
Why join
Ship directly to engaged users; your work is visible and high-impact
Build the core of an autonomous agent platform with real integrations and real workloads
Small, elite team; high ownership; fast decisions; zero bureaucracy
Vacancy posted 12 hours ago
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