Founding Engineer - Fullstack

Founding Engineer - Fullstack at DiligenceSquared (F25) $120K - $200K • 0.30% - 1.30% AI-powered market due diligence for investment decisions New York, NY, US Full-time Will sponsor 1+ years About DiligenceSquared About the role Skills: Next.js, Python, React, TypeScript, PostgreSQL We're looking for a Founding Software Engineer with deep expertise in full-stack development to help develop the next-generation AI platform for market due diligence. You'll own complete features end-to-end - from AI-powered backend systems to polished frontend interfaces that investment professionals in Private Equity, Hedge Funds, Private Credit, and Corporate M&A use to make billion-dollar decisions. About DiligenceSquared DiligenceSquared automates commercial due diligence for Private Equity funds. We're YC-backed, just raised a significant Seed round, and our clients include some of the world's largest PE funds. The market is $10B+ annually - PE funds pay McKinsey, BCG, and Bain $500K-$1M per report. Our AI agents do this work faster, cheaper, and with higher accuracy than any human. Our founders bought and sold these reports at Blackstone and BCG where they held senior positions. We have deep experience with the workflows and know exactly what the market needs - and now we're automating it. What you will do: Build new product features and experiences end-to-end, everything from database models to API endpoints, and integrating them with UI components for our Web App and AI Voice Agent application Design and build new AI-powered modules from scratch (e.g., market sizing, competitive analysis) that become core capabilities of our research platform Build and own product foundations across the stack (AI agent orchestration, voice AI pipelines, interactive data visualization, app and API performance, intelligent automations) Apply learnings from each project into the product, so we're 1% better everyday (Law of Compounding is real. After all, we are founded by investment professionals). Qualifications: 3+ years of professional full-stack development experience Strong proficiency in React/TypeScript and Python Experience building agentic systems with LLM platforms (Anthropic, OpenAI, or similar) Deep hands-on experience with LLMs in production - building reliable agentic systems, not just API calls Experience with PostgreSQL and SQL database design Experience with modern frontend architecture, state management, and API design Track record of shipping user-facing products end-to-end Bonus: Experience with Next.js and FastAPI Experience with Anthropic Claude API and Agent SDK Familiarity with agent orchestration frameworks Background building interfaces for AI/ML products or data-intensive applications Familiarity with vector databases and semantic search Experience with Supabase Previous startup experience Who you are: Love owning complete features rather than just frontend or backend pieces Can context-switch effectively between system design and UI polish Take pride in your code and want to work with others who do the same Act with Urgency so we can empower you with Agency Pay high attention to detail and are curious about how great products work Feel discomfort when things don't move as fast as you feel they should Interview Process Founders Call Technical Screen Paid Work Trial Offer