Gabriel Dehan

Web developer & Teacher

Single, 33 y.o.

Paris 🇫🇷 France

Fluent in 🇫🇷 & 🇬🇧

Worked in 🇨🇦 🇨🇳 🇫🇷 🇦🇺 🇳🇱 🇵🇹 🇲🇦 🇧🇪 🇯🇵

Currently: On the look out

To help you build amazing products.

Former Lead Teacher @Le Wagon

I love sharing knowledge!

updated: @January 21, 2025

Key Insights:

10+ years experience in Full-stack development (Ruby On Rails & Node / React)

5+ years experience teaching Web development

Experienced in API design & architecture

Dedicated to delivering satisfying and fair user experiences that respect the user’s time and the company values

Committed to improving developer experience by creating maintainable and well-documented systems

Deeply interested in everything AI and very up to date on the matter

My skills

As they say:

A Jack-of-all-trades: master of none, but oftentimes better than a master of one.

Back-end Development

API design and architecture

Ruby & Rails, Python

Typescript, Node (NestJS, Koa / Express), Meteor

SQL, GraphQL, MongoDB

DevOps & CI tools I am most familiar with

AWS / Heroku / Clevercloud

CircleCI, Travis, Github Actions

Artificial Intelligence

Regular user of AI tools like Cursor, ChatGPT, and Claude, with a local setup leveraging models like Qwen 2.5 and Whisper.

Comfortable with prompt writing techniques like CoT, n-shot prompting, role prompting

Knowledgeable in AI-driven approaches like Agents (CrewAI, Smolagents, Autogen), Embeddings based RAG, Function calling…

Front-end Development

React, Vue, Apollo, Electron, Stimulus, Meteor

HTML / CSS / SCSS

Tailwind, Bootstrap, Material, jQuery (🤔)

Also: I love atomic design.

UX & Product

Experience in UI & UX Design: Prototyping, Wireframing, User research, AB Testing…

Design

Figma, Sketch, Photoshop, Illustrator, InDesign

Work experience

🍃 freelance

🍁 employee

2023 – Today

🍁 Lead back-end Developer @ Klub

💻 Node / React

Technical design and assessment for new features

Back-end development in Node on multiple APIs and services

Cleaning up and improving existing code and erasing as much technical debt as possible

Maintaining front-end projects (React Native / React)

Test suite improvements

Writing documentation and architectural documents to improve future team members onboardings

2014 – Today

🍃 Freelance developer @ Me

Clients: Go Sport, APIE, Ubisoft, Fluidity, Squirrel, Doggui, Babasport, Shadow, HappyPal, Fuzz, and others…

More details on some of these missions below! 👇

2021 – 2022

🍃 Fullstack Developer @ HappyPal

💻 NestJS / React / GraphQL

Assisting the development team with the redesign of the HappyPal platform.

First half of the mission I was assigned to the front-end team and participated in the development of many features as well as setting up the i18n pipeline of the whole platform back to front.

For the second half of the mission I was mainly on back-end duties, during which I worked on fixing bugs and developing new features, most notably our internal user segments system. I also set up all the communication systems pipelines: segmented transactional emailing, generation of newsletters for specific user segments (and thus lots of Sendgrid headaches), push and in-app notifications, etc...

2019 – 2021

🍃 Front-end Developer @ Shadow

💻 Node / React

Development of new features and maintenance on various applications: SSO, Sales platform, Storefront website, Customer Account platform, the shadow launcher…

Rebuilding some of those platforms from the ground up using more up to date languages like Typescript.

When I left, we had finished migrated most of our applications to Typescript and React 17, with a few old legacy applications still using older React versions and Javascript.

2014 – 2019

🍃 Lead Teacher @ Le Wagon

💻 Ruby / Ruby On Rails / HTML & CSS / JS (jQuery at first, then vanilla)

Gave 250+ lectures 👨‍🏫 to more than 700 students 👩‍💻 across 8 countries 🇨🇳.

Accompanied hundreds of students in the development of their MVPs.

2019

🍃 Back-end Developer @ Babasport

💻 Ruby On Rails / React (JS)

Development of new features and bug fixes for Babasport’s online shop

Implementation of their time slots management and booking system.

2018 – 2019

🍃 CTO & Co-founder @ Poi Network

💻 Ruby On Rails / React (JS) / React Native (JS)

Conception of the Proof Of Impact protocol

System Architecture & API Design

In 2018 development of our MVPs consisting of :
- Poi API & Poi Adapter
- Our React Native application
- Poi Pay
- Poi Business

In 2019, development of the actual products while managing a small team of 4.

2017

🍃 Back-end Developer @ Ubisoft

💻 Ruby On Rails

Development of a platform for a launch event of one of Ubisoft flagship games.

The operation was an online video contest, and the product was a Rails application using external services to automatically add i18n subtitles to user submitted videos.

2016

🍃 Fullstack Developer @ La Réserve

💻 Ruby On Rails / React (JS)

Development of a React application allowing restaurants to handle their tables and the scheduling of customers and timeslots: La Réserve in action (early version, don’t mind the design)

The back-end was a Ruby On Rails 5 API

2015

🍃 Fullstack Developer @ Fluidity

💻 Ruby On Rails / BackboneJS

Development of an “idea box” application for the internal needs of the company

The front-end was a Backbone JS application and the back-end a Rails 4 API

2013-2014

🍃 CTO & Co-founder @ CoHoop

💻 Ruby On Rails, Node

Product conception & UX Design

API Architecture & Design

MVP Development

2013

🍁 Back-end developer (6-months traineeship) @ Tigerlily

💻 Ruby On Rails

Lots of performance monitoring and database optimisation

Back-end features development

Bug fixing & test suite improvements

2011 - 2013

🍁 Front-end developer (1-year+ traineeship) @ Novactive - Web agency

💻 EZ Publish (PHP based CMS) / HTML & CSS, jQuery, jQuery mobile, Backbone JS, Titanium, and way too many Internet Explorer 6 compatibility related shenanigans (ah, the good old days)

Worked on many projects for big french clients (Air France, La Poste, UFC que choisir, ...),

Ended up being the lead of the offshore front-end developer team

Education

2010 - 2013

💻 Cifacom, development & project management school

2009 - 2010

🎨 e-art sup, digital creation school

About me

I have been passionate about software engineering for the past two decades, with a focus on designing and crafting applications that deliver the best possible user experience.

Self taught from a young age, I have a fairly atypical journey, even spending time in an art school before going back to the tech side of things and finishing my cycle of studies at Cifacom, where I graduated with a Project Manager diploma in 2013 after a 2-year internship.

After graduating, I became Lead Teacher at Le Wagon (a Ruby On Rails coding bootcamp), where I taught hundreds of students across many countries, giving lectures as well as counselling them on their startup projects; an experience that has given me both a very solid technical foundation and a broad perspective in product design and user-centered problem solving.

In parallel — and since then — I’ve worked as a freelance fullstack developer, mainly focusing on Ruby on Rails and Node (and Typescript) on the back-end, and a whole lot of React on the front-end.

I’ve also co-founded a couple of startups with really exciting projects, and while they didn’t achieved commercial success, the managerial and technical lessons as well as the hands on product design experience I got there were invaluable.

Oddly enough, I think one of my greatest strength is my empathy, which drives the care I have for both my team and our users:

I always put the user experience first and I am adamant about respecting the user’s values and time when building new features.

I also find a lot of satisfaction in writing clean code, clear and exhaustive documentation and I always strive to craft the best developer experience I can for the rest of my team (or even my future self) and reduce friction as much as possible.

I always have a plethora of new project ideas so you’ll also find that I spend a decent amount of my free time designing and developing those, just trying things out.

If you want to take a look there, I am usually quite active on github where I maintain a few personal open source projects, one of them being a fairly-high traffic (~ serving 10k unique users/day) application called Dyson Sphere Blueprints. You can also check-out Chronicon DB, a front-end only and open source database for a very cool game.

So, if you’re looking for someone who blends technical know-how with strong interpersonal skills and loves to build user-focused products, feel free to email me!