Ruby on Rails
Teacher
at Simplon.co
I taught Ruby and Ruby on Rails as the lead technical formateur on Simplon's web developer bootcamp. My role covered the full back-end track — from Ruby fundamentals through to production Rails applications — as well as co-designing pedagogical exercises, mentoring students through their certification projects, and coaching career transitions into the industry.
France's inclusive coding school — born with Ruby on Rails
Simplon.co is a French École du Numérique founded on a social mission: making tech careers accessible to everyone regardless of prior education, age, or background — including people from priority neighbourhoods, career-changers, and seniors. Crucially, Simplon's very first training course, in 2013, was in Ruby on Rails, opening in Montreuil outside Paris. The school has since grown to 100+ campuses across France and internationally, but Rails remains foundational to its DNA.
6-month bootcamp — from zero to full-stack developer
The bootcamp was structured as two consecutive tracks. I taught the back-end track, but maintained strong continuity with the front-end track to ensure students could build fully integrated applications. Both tracks were 100% project-based — no academic exams, only deliverables.
HTML / CSS / JS / Ruby — the first three months
Though I was primarily the back-end specialist, I contributed to the front-end track's Ruby module and ensured the Ruby fundamentals were solid before students entered the Rails phase. A common failure mode in bootcamps is rushing to Rails before students are comfortable with Ruby's object model — I addressed this with dedicated OOP exercises.
Ruby on Rails — MVC to production deployment
The back-end track was where I spent most of my teaching energy. The goal was to take students from "I understand Ruby syntax" to "I can build, test, and deploy a production Rails application" in three months. The approach was entirely project-driven — concepts were introduced in the context of a real feature students needed to build.
| Phase | Concepts taught | Project milestone | Duration |
|---|---|---|---|
| Rails foundations | MVC architecture, routes, controllers, views (ERB), conventions, scaffolding | Build a working CRUD app from scratch without scaffolding | 2 weeks |
| ActiveRecord & DB | Migrations, associations (has_many, belongs_to, HABTM), validations, scopes, PostgreSQL basics, SQL JOINs | Add a relational data model to the app (users, posts, comments) | 2 weeks |
| Authentication | Devise gem, sessions, cookies, bcrypt, email confirmation, password reset | Full auth system — register, login, forgot password, profile | 1 week |
| Authorisation | Pundit policies, role-based access, admin vs. user scopes | Add admin panel with Pundit-protected routes | 1 week |
| File uploads & storage | ActiveStorage, direct S3 upload, image variants, CarrierWave comparison | User avatar + document upload to S3 | 1 week |
| APIs & background jobs | RESTful JSON API, HTTParty, ActiveJob, Sidekiq, ActionMailer | Consume a third-party API and send notification emails | 1 week |
| Testing | RSpec (model, controller, feature specs), Factory Bot, Capybara, TDD mindset | Write tests for an existing feature — red/green/refactor cycle | 1 week |
| Deployment | Heroku / Render, environment variables, production database, CI basics | Live production URL delivered and presented | 1 week |
| Final project | Full-stack Rails app, team of 3–4, Agile sprints, code review | Jury presentation — Titre Professionnel evaluation | 3 weeks |
Project-based learning — real apps, real code review
Every evaluation at Simplon was a project delivery, never a written exam. I designed the project briefs, the assessment grids, and led the code review sessions. The final project was evaluated by an external jury including industry professionals — replicating a real sprint review.
How I taught — principles & practice
Teaching Rails to career-changers with no CS background required a radically different approach from university teaching. The audience included former nurses, retail workers, and administrative staff in their 30s and 40s. The goal was never to make perfect computer scientists — it was to make confident, employable junior developers.
What my students went on to do
Simplon's model measures success by employment rate — not rankings or research output. The majority of my cohorts found junior developer positions within 3 months of graduation, primarily as Ruby on Rails developers but also as full-stack JS and PHP developers where the Rails foundation transferred well.