Senior Software Engineer - Devexp Team - ai H/F PayFit

Get to know us

Do you want to help us shape what the future of work will look like and how it will best embrace our life's aspirations? If this sounds like a journey you want to embark on, we may have the right role for you! PayFit is an intuitive software as a service payroll and HRIS solution designed specifically for SMBs.Since 2015, we have set ourselves a mission to simplify payroll for SMBs and enable employers and employees to grow together. We are a European company operating from 3 main countries (France, Spain, and the UK) where we are supporting over 20,000 clients.

Creating a fulfilling work environment and culture is also a core mission at PayFit, and our day-to-day work philosophy is reflected in our four values:

Care:We genuinely care for others whoever they are, whatever they think.

Excellence:We aim to improve and achieve better results every day.

Humility:Staying humble and exchanging transparent feedback helps us to grow and improve.

Passion:We are the architects of PayFit's success.

A key part of our culture, and essential for our success, is also improving the diversity of our teams and building an inclusive culture where you can be yourself at work.

This is why our recruitment focuses on the skills you demonstrate, and not only on your academic background or previous professional experiences. At PayFit we understand that you can gain applicable skills through a variety of life experiences and we are interested in knowing them, too.

Location :
The position is based in France

Position Overview

You will join the Internal Developer Experience team, whose mission is to empower PayFit's engineering organization by creating a world-class backend development environment. This team provides the tools, frameworks, and AI-enabled workflows that enable our 100+ engineers to ship faster, safer, and with greater confidence.

As we scale our product across multiple countries and expand our engineering organization, we need to ensure consistency, quality, and velocity across all backend development, while preparing our codebase and workflows for an AI-augmented future.

Impact - next 12 months

As a Senior Software Engineer in Internal Developer Experience, you will play a critical role in:

- AI Enablement: Animate the organization to adopt AI workflows for software engineers: making our codebase AI-friendly, building agent-compatible tooling, and evangelizing best practices across teams.
- Backend Framework Rollout: Work with our engineers teams to design and deploy a unified backend framework across the organization (conventions, architectural patterns, global standards), ensuring consistency and quality at scale.
- Developer Experience: Improve productivity, onboarding speed, and satisfaction for engineers by platformizing backend solutions, reducing friction, and building clear guidance.
- Community Building: Grow a thriving backend community at PayFit. Creating forums, office hours, documentation, and feedback loops that empower teams to self-serve and collaborate.

What you will do

- Design, implement, and roll out backend frameworks, standards, and tooling (NodeJS/TypeScript, monorepo patterns, event-driven architectures)
- Lead initiatives to make PayFit's codebase AI-friendly and agent-ready. Optimizing for code generation, code review automation, and AI-assisted development
- Collaborate with engineering teams to identify pain points, gather requirements, and prioritize high-impact improvements
- Build and maintain platformized solutions: shared libraries, CLI tools, templates, and developer portals
- Animate the backend community: organize working groups, publish guides, run workshops, and foster knowledge sharing
- Implement observability, monitoring, and quality gates for developer tooling
- Work closely with Staff Engineers, Engineering Managers, and SRE teams to align on architecture and best practices
- Track KPIs (adoption rates, developer satisfaction, onboarding time, code quality metrics) and iterate based on feedback

This Role is For You If

- You have 5-8 years as a Software Engineer, with deep expertise in NodeJS/TypeScript and building backend systems at scale
- You excel at community building and collaboration: comfortable evangelizing, teaching, and gathering feedback

- You have experience creating and maintaining backend platforms, monorepo tooling, or developer experience systems
- You have a product mindset: you iterate, track KPIs, prioritize ruthlessly, and ship incrementally
- You have an advanced understanding of AI-assisted development tools (Copilot, Cursor, etc.) and how to integrate them into team workflows
- You communicate effectively with cross-functional teams, focusing on outcomes and impact
- You focus on code quality, testing, and maintainability and understand the importance of developer ergonomics
- You are fluent in English (primary working language: French)

It would be great if you also have / Nice-to-have skills

- Experience working on platform teams or internal developer experience initiatives
- Experience with Nx, ArgoCD, Kubernetes, AWS or similar infrastructure/orchestration tools
- Familiarity with Event-Driven Architecture (EDA) and Domain-Driven Design principles

Interview process

1. Discovery Call: Meet a Talent Acquisition Specialist (30-45 min).

2. Discussion with an Engineering manager: Meet Côme, team's EM, to discuss technical aspects of your experience (45 min)

3. Technical Challenge #1: Coding challenge with a Senior Staff (1 hour)?

4. Technical Challenge #2: Discussion around Platform with team members with 2 team members (1 hour)?

Background Check (ISO27001 certification): identity, diploma, and past professional experiences will be checked after the offer.

What we offer

Flexibility: We believe it is key to producing your best work and being fulfilled. We therefore offer the possibility to work away from our main offices, within France, as well as abroad for a defined period. Further requirements may apply depending on the role and your overall experience.

Learning & Development: At PayFit, we offer a comprehensive learning platform that enables you to acquire new skills daily, supported by our company. We also have English language courses to improve your business communication vocabulary and get to the next level.

Career Development: We want you to progress and be free to choose which direction you want to grow. There are also opportunities for internal moves.

Health insurance: Henner Mutuelle Insurance (60% covered by PayFit, free coverage for children
Transportation: 50% of public transportation costs are covered by PayFit for those living within the Ile de France region, or assistance with sustainable mobility (a bicycle rental subscription, purchase of soft mobility equipment to get to work, etc.).

Meals: A restaurant card with our partner Swile (9€ per workday).

A Work Council grant: A monthly allowance to be spent on culture, sports, personal services, etc., as well as a vacation bonus.

Home office budget: A contribution in € per year to help you get set up in the best conditions. A MacBook is our standard working tool

Parental support program: Salary maintenance during the first month of parental leave.

Time off: 25 days of holidays + RTT days (depending on the contract).

Disability Inclusion: All of our positions are open to any person living with a disability. To guarantee equal treatment and opportunities, we will take, based on individual needs, appropriate measures to adapt the work conditions of PayFiters with disabilities, and if needed also during the recruitment process. Please let us know what you need and we will do our best to accommodate!