Junior AI Full-Stack Developer

About Lumen Dynamics Mission: "Connecting Antitrust People." The global platform for competition law — 20+ years, 150+ countries, ~50,000 professionals. Lawyers, economists, judges, regulators, academics: all shaping competition policy. We started as a challenger taking on established players. That DNA hasn't changed — now we're building with generative AI. What drives us: Excellence — scientific rigor and editorial quality in everything we publish. Innovation as a driving force — pioneering new formats, anticipating industry trends, now building with generative AI. And a global community connected through high-level dialogue and best practices shared across borders. What You'll Build You own RAG infrastructure for 330–430K legal documents. Chunking pipelines. Vector database tuning. API components. Real systems, real lawyers depend on it. Concrete work: Intelligent chunking for French court decisions (preserve precedent hierarchy) Weaviate integration, embedding strategy optimization, semantic search at scale RAG components: retrieval → reranking → context → LLM calls Evaluation infrastructure so domain experts measure correctness, not just plausibility Ship 3–5 features in month one Tech: Python, FastAPI, Weaviate, PostgreSQL, GCP. Plus: CrewAI/LangGraph/LlamaIndex, Pulumi/Terraform. A Typical Week Monday: Debug chunking pipeline mangling PDFs. Propose fix, pair, ship it. Tuesday: Embedding model struggles with French legal terms. Document, propose mitigation. Wednesday: Design caching strategy for API. Watch latency drop. Thursday: Code review. Close issues. Plan sprint. Who You'll Work With Anton Bossenbroek (CTO): 20+ years at BCG, Bain, EY, Deloitte, and C3.ai. Your primary technical collaborator on architecture and AI integration. Nicolas Charbit (founder): 20 years building Lumen Dynamics into the definitive antitrust platform. Shapes domain direction and product strategy. Small, focused, high-ownership team. This is a strategic AI initiative — you'll matter immediately. Who This Role Fits You ship real systems. You reason from first principles. You're a generalist ready to learn fast — APIs, databases, infrastructure, legal domain, all at once. Motivated by collaboration, mission, and growth. You ask until you understand. You Must Have Python: Non-trivial production code. Async, testing, error handling. Backend/API: Built and deployed a web service (FastAPI, Flask, Django). Linux & Git: Terminal-comfortable. Workflows, shell scripts, SSH. SQL: Write queries. Understand joins and indexes. Intellectual honesty: Admit unknowns. Growth mindset non-negotiable. Big Pluses Vector databases or RAG (Weaviate, pgvector, Pinecone) Agentic frameworks (CrewAI, LangGraph, LlamaIndex) GCP or cloud platforms Infrastructure as Code (Terraform, Pulumi) Law, legal tech, court decisions French language (A2+ valuable) Compensation & Timeline R$6,600/month (~€1,200), paid EUR via Wise. Independent contractor, monthly invoicing. Initial 3-month project engagement with clear path to ongoing collaboration at a higher rate. Start: ASAP, within 4 weeks. Interview Process Application — CV, GitHub, three written answers (submitted via application form below). 15-min intro call with Anton (CTO) — Who you are, what excites you, fit. Two 30-min deep dives — Architecture & trade-offs. Real RAG problem-solving. 20-min conversation with Nicolas (founder) — Domain understanding, alignment, culture. Timeline: 2–3 weeks, application to offer. Remote & Async English required. French a plus. Remote-first, async work culture. The CTO is based in Vancouver, the company in Paris. We coordinate across time zones — responsiveness matters more than fixed hours. Originally posted on Himalayas