Senior Fullstack Software Engineer (AI)

TL;DR

Senior Fullstack Software Engineer (AI): Building and scaling production AI features and agent-based systems for a conversational commerce platform with an accent on backend reliability, LLM integration, and event-driven architecture. Focus on designing multi-turn conversational behaviors, optimizing prompt evaluations, and turning complex shopper data into LLM context.

Location: Paris

Salary: €108,500 – €119,921

Company

AI-first conversational commerce platform for Shopify merchants focused on turning customer interactions into intelligent relationships.

What you will do

• Develop end-to-end AI product features across backend, APIs, and frontend (React).
• Build and refine evaluation workflows to measure and improve prompt and agent performance in production.
• Design and evolve the architecture for high-load, event-driven AI services and Temporal workflows.
• Transform shopper event streams and product data into actionable context for LLMs.
• Own the quality, reliability, and iteration of multi-turn conversational AI agent behaviors.

Requirements

• 5+ years of experience as a Fullstack Engineer shipping production systems.
• Production experience integrating LLMs into user-facing, multi-turn, or agentic systems.
• Strong backend foundations in Python and TypeScript.
• Experience designing systems that convert structured data (events, transactions) into LLM context.
• Hands-on experience with prompt evaluation and agent behavior measurement.
• Proficiency in building and operating APIs and event-driven services.

Nice to have

• Experience with LLM observability tooling.
• Proven track record of optimizing inference cost or latency in production.
• Background in e-commerce, merchant-facing, or marketing-tech products.

Culture & Benefits

• Access to premium AI tools (ChatGPT, Claude, Granola, and others).
• Annual L&D budget for continuous learning and AI exploration.
• Knowledge-sharing culture through dedicated AI channels and company-wide demo sessions.
• Inclusive environment committed to diversity and innovation.

Hiring process

• Recruiter phone screen and Hiring Manager interview.
• System Design and Live Coding interviews.
• Final interview.