Founding Full-stack Software Engineer

WHO WE ARE Lemrock builds the infrastructure of agentic commerce. Tomorrow, consumers won't just buy on e-commerce websites. They will discover, compare and purchase directly inside conversational AI interfaces like ChatGPT, Perplexity, and a growing long tail of specialized AI assistants. For brands, this is a major shift: if they are not present in these environments, they become invisible.

Our mission: enable any brand to exist, sell and distribute in this new channel. We raised a €7M seed round (the first in Europe on this market), with Jean-Baptiste Rudelle, founder of Criteo, on our board, and the Bpifrance Deep. Tech label. Today, Lemrock is already: - 100M+ conversations per month - 150+ brand clients - a $100B market structuring at high speed CONTEXT You'll join a small, high-ownership engineering team building production systems that serve millions of users.

We care deeply about code quality and clean architecture — and we intend to keep it that way as we scale. YOUR MISSION Your goal is to build and ship the product that powers Lemrock's commerce infrastructure — with full ownership, from design to production. Concretely, you will:

• Ship features end-to-end that reach millions of users — from data model and API design to the interface they interact with.
• Scale and harden our backend as traffic, integrations, and product complexity grow.
• Shape the architecture of the codebase — enforce clean boundaries, maintain modularity, and make decisions that compound as the team scales.
• Move fast across the stack — backend, frontend, infra, data — wherever the highest-impact work is on any given week. CANDIDATE PROFILE
• Strong academic background, proven professional track record, or hands-on entrepreneurial experience - 2+ years of hands-on software engineering experience
• Deep proficiency in TypeScript
• Experience with structured backend architectures (DDD, hexagonal, or similar)
• Has owned features end-to-end: data model → API → frontend → deployment
• Comfortable with AI coding tools (Cursor, Claude Code)
• Thrives in ambiguity and 0-to-1 environments — ex-founders or entrepreneurial mindsets are a strong fit
• Professional proficiency in French & English TECH STACK Core (required)
• TypeScript, NestJS, React
• PostgreSQL, Redis
• Docker
• Clean architecture patterns (hexagonal, ports & adapters) Bonus (appreciated but not required)
• GCP (Cloud Run, Pub/Sub, Big. Query), Terraform
• Vector databases, embeddings, LLM integrations
• Domain-Driven Design (DDD), CQRS
• Tan. Stack (Router, Query, Table), shadcn/ui, Tailwind, Vite
• Durable workflows (Inngest, Temporal) WHY JOIN US
• Join a company in early breakout mode, already generating revenue, with a clear technological edge and strong financial backing to fuel its growth
• Work directly with an experienced team: two repeat YC founders who've scaled product & tech before, a former strategy/innovation director (10 years in the sector), and ex-strategy consultants (McKinsey Quantum. Black, BCG)
• Be part of the next structural shift of the web — agentic interfaces
• Own mission-critical topics, grow fast, and shape the company's future trajectory PACKAGE Competitive salary + equity, disclosed during the interview process.