Senior Rails Engineer - AI-Driven Product, Paris

Le Wagon, Inc.; Paris; On-site; EUR 90,000 - 120,000; Full time

Job summary

Le Wagon in Paris (11e arrondissement) is seeking a Senior Software Engineer to join its Engineering team. You will work with senior engineers across Paris, Tours, and Madrid to build tools and features using Ruby on Rails, Redis, PostgreSQL, and modern CI/CD practices.

You will own features end-to-end, lead deployments, mentor colleagues, and help shape the product roadmap. Fluency in French and English and a strong product mindset are required.

Qualifications

• Have >6 years of software engineering experience including Ruby on Rails.
• Fluent in French and English.
• Experience shipping production Rails apps and ownership of features.

Responsibilities

• Collaborate with stakeholders to shape features from concept to delivery.
• Design, implement, and review production code for quality and scalability.
• Take ownership of the release process and coordinate deployments.
• Mentor peers to raise technical quality across the team.

Skills

Ruby on Rails

Mentoring

Cross-functional collaboration

Communication

Education

Le Wagon Web Development Bootcamp

Tools

Git

Github

GitHub Actions

PostgreSQL

Redis

Docker

Ansible

Job description

We are hiring a Senior Software Engineer in Le Wagon's Engineering team. The job is based in Paris (11e) and requires speaking French 🇫🇷 and English 🇬🇧 fluently.

The Engineering team 🛠

We are a team of 5 Software Engineers based in Paris, Tours and Madrid.

Our mission is to build the right tools and features to support Le Wagon's consolidation and growth. We work in cycles and follow theShape Upmethodology.

All engineers have a strong product culture and are involved in our product cycles, from shaping to release and adoption.

Our apps are developed in Ruby on Rails (v7 and v8), we work w/ Redis, PostgreSQL, Turbo, Stimulus, use Git and Github, implement our CI w/Github Actions, deploy to Scalewayusing Dokku and monitor errors and performance w/ AppSignal. We also run services using Docker, created and managed via Ansible Playbooks.

We integrate w/ many APIs including Sendgrid, Docusign, Hubspot, Zoho, Xero, Odoo, Edusign, Notion, Slack and Google.

At Le Wagon, we work w/ Dust and build agents to automate all repetitive workflows. Additionally, every engineer has their own subscription to Claude Code.

Mission

You will work with senior engineers who have been working at Le Wagon for more than 5 years and who all did the Web Development bootcamp as students, teachers and batch managers before joining the Engineering team, and with mid-level engineers who have joined the Engineering team around 2 years ago after gaining first professional experience.

You will work on Projects likeProviding an AI assistantto studentsembedded in our pedagogical platform, where we collaborated hand in hand with:

• our Data Squad who implemented an API connected to OpenAI to provide students with contextual guidance w/o handing over code solutions
• our Head ofOperations as project stakeholder who centralized needs and requirements, and coordinated the beta test in two selected batches

Every 2 months, Engineering gathers w/ a handful of well identifiedstakeholders to discuss the next cycle's main needs and how to best invest Engineering work to provide the maximum impact to the company based on the current strategy. Around 10 to 15 projects are built per cycle.

Beyond our roadmap projects,we frequently collaborate with the Data Squad on providing applicative insights on our PostgreSQL Databases that are sourcing our DataLake on GCP.

Role responsibilities

As a Senior Software Engineer, you will:

• Collaborate with content, operations, finance, marketing and other stakeholders to shape features from concept to delivery
• Design, implement, and review production code, ensuring quality, maintainability and scalability
• Take ownership of the release process, coordinating deployments and ensuring smooth rollouts
• Investigate and resolve complex issues in production, contributing to reliability and meeting SLA expectations
• Mentor and guide peers to raise technical quality across the team

This role is for you if you:

• Have more than 6 years of relevant experience as a Software Engineer, including in Ruby on Rails
• Take ownership of features and systems end-to-end, making technical decisions that balance short-term needs and long-term scalability
• Have strong experience building and maintaining production Ruby on Rails applications
• Use AI-assisted tools thoughtfully to improve development velocity and code quality
• Write clear, well-tested code and make pragmatic tradeoffs between simplicity, performance, and maintainability
• Diagnose and resolve complex problems across the stack, including in production
• Communicate effectively with engineers and cross-functional partners, and contribute constructively to technical discussions
• Plan and execute work independently, balancing priorities, scope, and deadlines
• Apply a strong product mindset and enjoy working closely with engineering stakeholders to shape solutions
• Are fluent in French and English

It's a plus if you also:

• Have an eye for UX and UI, and care about building intuitive, user-centered experiences
• Are comfortable with modern DevOps practices and operating production systems
• Have prior experience in EdTech or other mission-driven, user-facing domains
• Did the Le Wagon Web Dev bootcamp 🙌

Application process

• Online application
• Introductory screening call
• Technical deep-dive interview (60 minutes): discussion of a recent project or feature you worked on, with a focus on architecture, tradeoffs and system design thinking, optional live coding
• Working style & collaboration interview (30 minutes): learn about how the team works and how you collaborate
• On-site team meeting in Paris: meet the team in person and get a feel for how we work together