Full-Stack Developer - Freelance

About Us
We're building a B2B sales intelligence platform for international trade. Our software helps companies discover new buyers and suppliers worldwide and connect with the right decision-makers.

Most businesses struggle to find reliable partners abroad. We're making global trade accessible to everyone, not just large corporations with dedicated export sales / procurement teams.

We're a young and growing company with active clients using our platform daily. Our team is lean, 2 founders, a strong team of advisors, a lead developer, and we're looking for a full-stack developer and other roles to join us and help build the next biggest trade market intelligence platform in the world.

Role Description
We're looking for a freelance full-stack developer with a strong backend focus. You'll ship new features, solve real problems, and help shape the technical foundations of a product that's growing.
Today, one the founder handles the product and works with one technical lead. You'd be the second person on the tech side, a structuring role with real impact and direct input on key decisions.

You'll have full ownership of your work, from idea to production. That means making technical decisions yourself, validating your own features, and shipping with confidence. You won't be alone, you'll work closely with the technical lead and get support on architecture and complex decisions. But you'll still own your deliverables.

You will:
Ship product features end-to-end
Debug and resolve production issues (performance bottlenecks, race conditions, data inconsistencies)
Own our third-party integrations
Own background jobs & webhooks reliability (Inngest, retries, idempotency)
Optimize PostgreSQL & ClickHouse queries for high-volume data (billions of rows)

Team & Working Environment
You'll join a very small team with few formal processes and a product that's still early-stage. This means strong autonomy and individual responsibility. You'll own problems end-to-end, make technical trade-offs on your own, and validate your work before shipping.

Day-to-day, you'll be working on a product that's already in production, used by real clients. That means debugging real incidents, making technical trade-offs without detailed specs, and iterating fast: ship, observe, improve. We have two daily syncs, one in the morning to align, one at end of day to review progress

Tech Stack
Next.js 15 (API Routes, Server Actions, React)
PostgreSQL + Supabase + ClickHouse
Vercel, Inngest, Clerk
TypeScript

Nice to Have

Architecture experience: designing or restructuring systems at scale (not just building within one)
Analytical/columnar databases (ClickHouse, BigQuery, DuckDB)
Security: multi-tenant isolation, roles & permissions, secrets & data security (access scoping, encryption at rest/in transit)
GDPR & data protection

Must Have
3+ years Node.js/TypeScript backend experience
3+ years building production systems with Next.js
Strong PostgreSQL experience (transactions, performance, indexing, connection pooling)
REST API design & security (auth, input validation, rate limiting)
Experience stabilizing and refactoring existing codebases, not just greenfield
Comfortable working across backend and the Next.js app layer

What are you looking for in a hire?
Curious & Growth-Oriented: You stay up to date with new tools and frameworks, and actively seek opportunities to expand your skills
Resourceful Problem-Solver: You take initiative when facing blockers and find solutions independently
Strong Ownership Mindset: You care deeply about the end-user experience and aren't afraid to challenge decisions to improve the product
Execution-Focused: You prioritize shipping and iterating over perfection
Proactive Communicator: You keep the team informed, articulate ideas clearly, and ask for help when needed
Agency: You don't wait for permission or perfect specs, you decide, act, and flag it.
Flexible: Priorities shift fast, you switch from a data pipeline to a React fix without friction.

Why Working With Us?
Real impact from day one: your code ships to production and is used by real clients immediately
Learn fast: work directly with the founders on a product that's growing and evolving rapidly
Ownership: you won't execute tickets, you'll own problems and solve them
Early-stage opportunity: join at 6 months in, grow with the company as we scale
Autonomy: you're trusted to make decisions and work independently, with guidance on priorities and people around to help when needed

Contract: Freelance, with opportunity to convert to CDI (Contrat à Durée Indéterminée)
Compensation: $3,000–$3,500/month
Location: On-site in Paris preferred, open to full remote for other European locations (Full remote, CET±2)
Engagement: Full-time