Full-stack Engineer (Agentic AI)

Evaneos; Paris; Hybrid; EUR 75,000 - 84,000; Full time

Benefits offered by this job

HQ in Paris (La Voyagerie)

Up to 3 days remote per week in Paris

Remote work from abroad several times/

Travel budget via CSE

Wellpass

25 paid leave days + 14 RTT

Job summary

Evaneos is seeking an AI Product Engineer in Paris to design, build and operate AI-native travel experiences used by real travelers. You will own end-to-end product development, from problem framing to live monitoring, working with product, design and business stakeholders.

You will craft agentic AI architectures and ensure observability, performance, and cost controls while shipping products that improve conversion and user experience.

Qualifications

• Design and ship AI-native travel experiences for real users.
• Own product lifecycle from framing to live monitoring.
• Build agentic AI architectures and infra for production use.

Responsibilities

• Design and ship AI-native travel experiences used by real travelers.
• Own end-to-end product development from problem framing to live monitoring.
• Collaborate with product, design, and business stakeholders to shape direction.
• Maintain observability and guardrails for LLM systems and tool calls.
• Balance quality, speed, and cost in production environments.

Skills

AI product engineering

Full stack development

Observability for LLMs

Problem framing

End-to-end ownership

Product direction

API integration

Tools

Python

TypeScript

Langfuse

Langsmith

Langchain

Claude SDK

OpenAI API

Anthropic API

Gemini API

Mistral API

Job description

At Evaneos, our mission is simple: to help travelers experience trips that are more local, more responsible, and more human, all around the world.

Within the Innovation Department, the Pathfinder team is reinventing how travelers design their tailor-made trips, with AI as the central lever of the experience.

We are hiring an AI Product Engineer to ship AI-native travel experiences used by real travelers in production. You’ll design, build, and operate AI products powered by agentic architectures, working end-to-end from problem framing to live monitoring, always in service of real user and business needs.

Your impact: you'll build traveler-facing AI products that move metrics on conversion, experience, and cost. Two are already live and serving traffic: an AI trip designer that helps travelers explore and customize itineraries and a conversational experience that turns their intent into a structured travel project local agencies can act on. Real products, not internal tools.

The innovation Department

Within the Innovation Department, AI runs on two complementary fronts:

• Pathfinder: we design and build AI-native products to unlock new growth opportunities and keep Evaneos at the forefront of its market.
• AI Company: we solve real team problems to improve internal efficiency, accelerate execution, and build a practical AI-native culture.

You’ll join Pathfinder.

It’s a small, focused team:

• Lou Anfriani (Product Designer),
• You (Full stack Engineer).

The team reports to Romain Quilliot (Head of Innovation), who leads strategy, operations, and execution. By design, the team member owns it’s direction and proposes initiatives — with direct exposure to C-level leadership on product and business strategy.

Our stack, at a glance

Languages: Python, TypeScript

AI/LLM: LiteLLM Gateway, Langfuse, Langsmith, multi-provider (Anthropic, OpenAI, Gemini, Mistral), Langchain DeepAgents, Claude Agent SDK

• Design agent architectures: runtime, tool systems, orchestration patterns, middleware, state management, RAG. Choose the right pattern for the right problem!
• Own context engineering: shape what the models see and find ways to better steer the model and system, raising quality while controlling cost.
• Make quality measurable: build evaluation pipelines (offline benchmarks plus online metrics) and observability to catch hallucinations, drift, and regressions before users do.
• Own the economic viability: once something is live, find the right balance of quality, speed, and cost.
• Keep it running: debug production issues on non-deterministic systems, handle model migrations when providers change their APIs, and deal with structured output failures and tool call errors.
• Own the infra: You build it, you ship it. Keep the dev environment fast and the deployment pipeline reliable.
• Own problems end-to-end: from framing to resolution, in collaboration with product, design, and business stakeholders.

Be a bridge between tech and product

• Take an active part in product direction, grounded in real user and business stakes.
• Translate technical constraints into product options, and explain the paradigm shifts AI brings.
• Proactively communicate on progress, decisions, and blockers: position yourself as an enabler for the team.

Grow our internal AI community

• Co-lead the AI Champions Tech program, leveling up Product & Tech across Evaneos on AI practices and knowledge.
• Share your learnings with the Innovation team and wider tech community.
• Run workshops and talks that demystify what matters in the agentic era.

You build the product, not the platform. Focus on shipping AI experiences directly to travelers: real users, real conversion, real business impact.

Full ownership in a team that fits in one room. No ticket queues, no handoffs between ML and product teams. You frame problems with the PM, design solutions with the designer, build and ship them yourself, then watch the traces to know if it works. The loop is tight and you own all of it.

AI at the core of a 15-year-old profitable marketplace. This isn't a startup burning cash on an AI bet. It's an established travel company with real revenue, real users across 160+ destinations in over 5 markets, and a strategic conviction that AI will reshape its core experience. Startup autonomy with business-model gravity.

What's in it for you?

• La Voyagerie: our lively HQ in the 9th arrondissement of Paris
• Based in Paris? Up to 3 days of remote work per week.
• Fully remote? Up to 2 consecutive days on-site per month when the whole team comes together in Paris.
• Travel budget through the CSE to experience Evaneos trips.
• Remote work from abroad several times a year.
• 25 paid leave days + 14 RTT days.
• Choice of PC or MacBook Pro.
• Wellpass (yoga, meditation, sports partially covered).
• Cultural lunches, seminars, afterworks, and regular team moments.

Salary: €75–84K gross annual, based on experience.

What we're looking for

You may be a great fit for this position if:

• You have at least 5 years of software development experience and are comfortable with APIs and data stores.
• You've built and deployed AI agents in production with real users: not just PoCs or hackathon projects.
• You've set up or contributed to LLM evaluation pipelines (offline benchmarks and/or online metrics) and have designed guardrails.
• You have hands‑on experience with observability for LLM systems: tracing, monitoring, diagnosing regressions from traces (Langfuse, LangSmith, or equivalent).

Mindset & ways of working

• Curious and passionate about AI: you keep up with the state of the art, test things to understand them, and apply what you learn to what you build.
• Full‑stack at heart: in a small team, you're happy to touch front, back, and infra. No “That’s not my job.”
• Strong ownership: you spot problems, propose solutions, and move forward while keeping everyone in the loop.”
• Product appetite: you want to understand users, conversion, and the business. Engineering is a means to an end: crafting meaningful experiences and solving real customer problems.
• Team player: You like pairing, sharing knowledge, communicating clearly, and pulling in the same direction.
• Fluent in professional English.

You'll thrive here if:

You want to build and ship AI products to real users, not do pure ML research.

You care about the product outcome, not just the technical pipeline.

You're comfortable working daily alongside product, design, and business stakeholders.

Interview Process

We are committed to creating an environment where everyone feels respected and included. We strive to provide equal employment opportunities, regardless of gender, sexual orientation, background, disability, or any other characteristic that makes you who you are. Our goal is simple: to ensure that everyone can thrive, feel safe, and be treated with respect.

In French and/or English:

• RH call with our Talent Acquisition Manager (Greismar): Initial chat to get to know you, learn about your work experience, and how they connect to the role 30 - 45 minutes
• Technical interview with Romain Q and one engineer: ways of working, collaboration and live session with your favorite coding agents + discussion on agentic architecture and system design. 1h30
• Product discussion with Lou or Clément & Jocelyne: discussing how you work with product teams and make informed decisions.
• Final conversation with Romain R, Chief Product Officer 30 minutes

A quick word on how we read your application

To give every candidate a fair shot and the attention they deserve, we sometimes lean on AI tools to support parts of our hiring process: to help review applications or assess responses. These tools support our team and help us stay consistent, but they don't make decisions for us. Every final hiring call is made by a person. Questions about how we process your data? Feel free to reach out :)