Backend Engineer

Fakto; Neuilly-sur-Seine; On-site; EUR 100,000 - 160,000; Full time

Benefits offered by this job

Equity stake

Senior team

Office in Neuilly

MacBook Pro

Job summary

Fakto is building the Cost Intelligence platform for how companies spend, with AI agents that understand supplier relationships, enforce agreements, and help decide what to buy.

We're a fast-growing Paris-based team and value an ambitious, international culture. You will be among the first engineering hires, shaping the product and the architecture.

You will own the data backbone, collaborate with founders, and ship features that scale to Fortune-500 buyers.

Qualifications

• Strong in data modeling, SQL and API design.
• DevOps / SRE experience with Docker, Kubernetes, CI/CD and observability.
• Ownership mindset with proactive communication and deadline awareness.
• Curiosity about LLMs and integrating them into the product.

Responsibilities

• Co-own the technical and product strategy.
• Turn client signals into product features and abstractions.
• Build the data backbone including contracts, invoices, and operational data pipelines.
• Ensure enterprise-grade security, reliability and data governance.
• Contribute to the evolving architecture as the product expands.

Skills

Data modeling

SQL

API design

Tools

Docker

Kubernetes

CI/CD

Observability

Job description

Large companies spend billions with their suppliers, yet few truly see or control that spend. Fakto is building the Cost Intelligence platform for how companies spend: AI agents that understand every supplier relationship, enforce what was agreed, and increasingly help decide what to buy, from whom and at what price. We start where the money leaks today, in the gap between what's negotiated and what's actually paid.

We're a fast-growing team in Paris, and we care a lot about building a healthy, ambitious, international culture.

What you'll do

You're among the first engineering hires, closer to a founder than a senior IC dropping into a defined role. A year from now, parts of this section will look obsolete, and you will have helped rewrite them.

What we can tell you is what you'll be responsible for:

• Co-owning the technical and product strategy. What we build, what we don't, what we standardise vs. keep bespoke, where the moat actually is, what the architecture looks like in 18 months.
• Turning client signal into product. You'll sit close to the problems clients hand us: messy contracts, opaque billing, edge cases nobody warned us about. Spot the pattern, propose the abstraction, ship the thing that makes the next ten clients easier.
• Building the data backbone the agents run on. Every finding Fakto surfaces rests on contracts, invoices and operational data pulled from our clients' systems. You'll design the data model, the pipelines and the APIs that make that data trustworthy, and the integrations that let us act back inside those systems.
• Making it enterprise-grade. Enterprise customers ask hard questions about security, reliability and where their data lives. You'll help own the answers: infrastructure as code, observability, access control, and the discipline that lets a small team run software large companies trust.
• Whatever else it takes. Some weeks that's hardening something before a client demo. Some weeks it's a clean-sheet prototype on a new use case. At our pace, the job rewrites itself every quarter, and you help write it.

You won't do any of this alone. All three founders are deeply technical and the CTO will be in the code with you.

Why this role, right now

• Join a deeply ambitious team. We're backed by Tier 1 investors (the funds behind Pigment, Revolut and Ramp) and already have LLM-based systems running for enterprise clients.
• The technical surface is genuinely hard. Reconciling structured and unstructured financial and operational data at enterprise scale: modeling messy documents, building pipelines that scale reliably with volume and clients' data diversity, and shipping them on production-grade infrastructure for Fortune-500 buyers. It is not a wrapper on an API.
• Large scope, large upside. You'll report directly to the CTO and have a real say in architecture, hiring bar, engineering culture and product roadmap. If you want to start a company one day, there's no better seat to learn from.
• A culture of ownership, not face time. We don't normalise working outside office hours. We also don't pretend client deadlines aren't real. If the work is done, leave early. If a client demo is tomorrow and something's broken, we expect you to care.

What we're looking for in you

The non-negotiables

• You're strong in data modeling, SQL, API design, and systems that stay correct when the input is messy. And you've touched DevOps / SRE / infra seriously enough to have opinions about Docker, Kubernetes, CI/CD, observability and what "production-ready" actually means.
• You're curious about LLMs. You don't need to have shipped one: they're part of the product and you'll work next to them every day, so what we care about is that you see that as an opportunity, not a price to pay.
• You have ownership instincts. If something's late and the client demo is tomorrow, you don't need to be told.
• You're fit the team. Healthy disagreement, low ego, kindness and the ability to hold a high bar without making everyone miserable.

Strong bonus

• You have 4+ years of professional engineering experience.
• You've owned a data-intensive system end to end: the schema, the pipelines and the way it was exposed to the user.
• You've worked in a true startup environment where the line between back-end, infra and "whatever needs doing" is blurry.
• You've done some front-end (React or otherwise) and don't run away from it - but you don't want to live there full-time.

We care less about

• Years of experience. Grit and curiosity beat tenure at this stage.
• Having professional AI experience. If you've never shipped an LLM feature, you'll learn it here with people who have.
• A perfect match on all five buckets (back-end, infra, security, data, front-end). One deep strength + two genuine curiosities is plenty.

What we offer

• Meaningful early-employee equity.
• A small, senior team. You'll help build what takes us to Series A and beyond.
• An office we actually like coming to at Neuilly Lab, one minute on foot from Les Sablons metro (Line 1).
• The best tools. Latest models, best stack, a MacBook Pro, no procurement battles to use Claude or anything else that makes you faster.

Hiring process

We've designed this to be fast, respectful of your time and high signal on both sides.

• 30-minute intro call with Charles (CTO).
• Time-constrained technical exercise. Delivered within ~two hours of receiving it. Done from home.
• Technical debrief call with Charles. We care less about whether the code is perfect and much more about how you reasoned through your choices and what you ran out of time for.
• Founders' fit conversations (in person). You meet the other two co-founders, Benjamin and Nicolas.
• Offer & references.

If at any point we don't think it's a fit, we'll tell you quickly and honestly. We expect the same in return.