Freelancer profile translated to English.
Back to original languageAbout Alex
Ruby on Rails developer since 2017, I assist startups and SMEs in the design, architecture, and evolution of their web applications.
I am not just a developer: I am also a SaaS entrepreneur.
I have designed and launched several platforms from scratch (multi-user, Stripe payments, advanced dashboards, interactive maps, React Native mobile apps).
👉 My strength: understanding the business challenges behind the technology.
💻 Technical Expertise:
- Ruby on Rails 5 → 8
- Hotwire / Turbo
- REST & JWT APIs (Devise, Devise-JWT)
- Stripe & Stripe Connect
- PostgreSQL
- Sidekiq / asynchronous jobs
- RSpec / automated tests
- Deployment (Docker, CI/CD, Kamal)
- React Native (Expo) for IOS & Android mobile applications
🧠 What I bring
- Clean and scalable architecture
- Maintainable and tested code
- Product vision & UX optimization
- Performance and profitability-oriented approach
- Ability to take over an existing project and structure it
I can be involved for:
- MVP creation
- Technical redesign
- Audit & optimization of a Rails project
- Addition of complex new features
- Occasional technical supervision
🎯 My way of working:
- Clear and structured communication
- Long-term vision (no "quick & dirty")
- Understanding of business needs
- Autonomy and proactivity
If you are looking for a developer who understands both technology and business, let's talk.
French
Native or bilingual
English
Fluent
Can work on-site
Paris (up to 50km), Bordeaux (up to 20km), Paris (up to 40km)
Experience
- MyUnisoftRuby on Rails Backend DeveloperSOFTWARE PUBLISHINGMay 2025 - September 2025 (4 months)Toulouse, FranceDesign and development of an intermediate API (technical gateway) between two legacy systems to ensure their interoperability and feed a new mobile application.Implementation of a data synchronization and transformation service allowing:- Unification of heterogeneous data formats- Secure exchanges- Exposure of structured endpoints for mobile consumption- Improvement of performance and maintainability
- StockProSenior Ruby on Rails Backend DeveloperCIVIL ENGINEERINGDecember 2021 - May 2025 (3 years and 5 months)Paris, FranceOnline marketplace dedicated to depreciated products in the construction sector:Maintenance, bug fixing, and testing on the existing codebase.Optimization and performance improvement of the application.Design and development of new back-end features.Implementation of EDI interfaces for integration with major companies' ERPs.Integration and replication of listings via API on external marketplaces (Google Shopping, eBay, ADEO).Implementation and configuration of Elasticsearch for improved search on new models.Development of a relevance algorithm based on personalized scoring.Technologies used:- Ruby on Rails (API)- Elasticsearch- Heroku- Amazon S3- Sellsy- Stripe- RSpec & FactoryBot
- FirecalBuilder - React Native / Ruby on RailsPUBLIC SECTOROctober 2020 - Today (5 years and 10 months)Toulouse, FranceArchitecture and development from scratch of two platforms designed to facilitate the management of firefighter associations:First platform dedicated to managing member consumption, stock tracking, and rental of services and apartments.Second platform specializing in sector mapping for calendar distribution and tracking of donations collected by associations.Stack:- Ruby on Rails- React Native (Expo)- Jquery- Bootstrap- Capistrano- MailJet- Stripe- OpenStreetMap- MariaDB- Leaflet- Ngnix
Reviews
C
Clementine
Appui Full stack: création d'une nouvelle expérience pour la capture des choix utilisateurs - kelvin technologies
Reviewed on 7/3/2026
Great experience with Alex: he supported our Ruby full-stack team during an EPIC delivery rush. Very quick onboarding, smooth communication, excellent ability to step back from his scope and challenge the product team, proposing technical solutions to meet the needs, incredible velocity. We'll stay in touch for the future!
Aurelien
Intregration Audit SEO - Ruby on Rails - Ouipharma SAS
Several days project
-
Reviewed on 4/7/2026
Very satisfied with the work done by Alex. He managed the implementation of all recommendations autonomously! I will use his services in the future.
Recommendations
These freelancer profiles also match your criteria
Agatha Frydrych
Backend Java Software Engineer
4.7
(3)
2
Baptiste Duhen
Fullstack developer
4.6
(4)
5
Amed Hamou
Senior Lead Developer
4
(2)
7
Audrey Champion
Web developer
4.3
(3)
4
Education
- Master in Web Project Management, Computer EngineeringToulouse Ynov Campus2019Master Chef de Projet Web, Ingénierie informatique
- Bachelor's degree, Software EngineeringYnov Informatique2017Bachelor's degree, Ingénierie logicielle