Founding Full-stack Software Engineer
Lemrock · Paris · hybrid
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 DeepTech 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, BigQuery), Terraform
- Vector databases, embeddings, LLM integrations
- Domain-Driven Design (DDD), CQRS
- TanStack (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 QuantumBlack, 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.