Freelancer profile translated to English.
Back to original languageAbout Antoine
I have been building B2B SaaS in Ruby on Rails since 2016, from requirements gathering to production deployment.
My background combines team missions (Accenture for the World Economic Forum, Kelio, Season Education) and independent product design: I designed the Nekka SaaS alone from A to Z and operated it for 2 years in a real professional environment, before selling it in 2025 to the client who wished to internalize it.
Beyond pure development, I regularly take on technical lead roles on assignments: mentoring junior developers, transmitting best practices, technical scoping in direct contact with end clients. My Professional Scrum Product Owner certification translates concretely into an ability to arbitrate between business value and development effort, and to challenge requests when necessary.
WHAT I DO
▸ Design and development of B2B SaaS (Ruby on Rails, API architecture, fullstack)
▸ Taking over and modernizing existing Rails applications (refactoring, security, DevOps)
▸ Deep Ruby ↔ Salesforce integration (via API, without Apex) and other CRMs (HubSpot)
▸ Technical lead on assignments, mentoring juniors, product scoping with clients
MAIN STACK
Ruby on Rails · Grape · REST API · PostgreSQL · Redis · Sidekiq · Docker · GitHub Actions · Heroku · Render · GCP · AWS · React · Angular · Nuxt.js · Salesforce · HubSpot · Stripe · TypeScript · Python
French
Native or bilingual
English
Native or bilingual
Remote only
Primarily works remotely
Experience
- KelioFullstack DeveloperSOFTWARE PUBLISHINGJune 2025 - February 2026 (8 months)Cholet, FranceFullstack mission on an HR SaaS (ATS / payroll / time management suite), within a team of 8 people (Tech Lead, architect, developers, PO, testers).Took over a stack composed of a Ruby on Rails backend on Heroku and several Nuxt and Angular frontends.Main contributions:▸ Streamlining a fragmented authentication system with security flaws; convergence towards session cookies, addition of Google OAuth and email OTP magic link.▸ Participation in a complex business statistics module (5-year aggregations, inter-client comparison, daily refresh).▸ Implementation of DevOps procedures: Dockerization, Heroku & Render deployments.Practiced TDD, code review, product collaboration.
- NekkaNekkaRETAIL (SMALL BUSINESS)September 2023 - September 2025 (2 years)Nantes, FranceDesign, development, and operation of a B2B SaaS for mobile repair professionals, for tracking customer repairs (notifications, statuses, statistics).Project born from a store owner's need who couldn't find a suitable tool on the market.Full role throughout the lifecycle:▸ Product scoping: requirements gathering, feature prioritization and arbitration (practical application of PSPO certification), ability to challenge requests to maintain tool simplicity.▸ Fullstack design and development: Ruby on Rails backend exposing an API, Angular frontend in TypeScript, authentication, asynchronous tasks, email notifications, Stripe integration for billing.▸ DevOps & operation: Docker containerization, GitHub Actions CI/CD, Jelastic Cloud deployment, New Relic and Rollbar monitoring.Product operated for 2 years in a real professional environment (2 stores, 7 daily users), then sold in 2025 to the historical client who wished to internalize it.
- Cérès growth marketingTechnical LeadE-COMMERCEDecember 2021 - July 2023 (1 year and 8 months)Technical lead within a Growth Marketing agency of about ten people (mostly marketing), leading a technical team of 2 (one junior developer and myself).Direct technical interface with the agency's end clients: scoping needs, translating them into technical specifications, architecture choices, delivery management.Achievements:▸ Development of about ten connectors between HubSpot and clients' business systems (billing tools, third-party CRMs, etc.), with bidirectional synchronization.▸ Automation of marketing workflows to industrialize Growth campaigns.▸ Deployment on Google Cloud Platform (Cloud Functions, Cloud Scheduler, Secret Manager).Mentoring the junior developer: code review, pair programming, skill development in the GCP and Python ecosystem.
Reviews
Gauthier
SEASON
Reviewed on 1/4/2022
Antoine delivered very clean code within controlled time and costs. He quickly understands functional needs and finds relevant technical solutions to meet them.
Simon
Cérès growth marketing
Reviewed on 3/1/2022
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Education
- Computer Science Master's Degree, COMPUTER SCIENCE FOR AEROSPACE (CSA) trackUniversité Paul Sabatier Toulouse III2021Grade: Master Activities and societies: Systèmes critiques (embarqués, temps réel) - Sécurité - Parallélisme et systèmes distribués - Architecture système et réseaux pour l’aérospatial - Analyse d'image et Intelligence artificielle - Base de données (parallèle et répartie, mobiles et embarquées) et algorithmique Ce Master international dispensé en anglais a pour vocation de former des ingénieurs à la conception de systèmes informatiques complexes.
- Computer Science Bachelor's DegreeConservatoire National des Arts et Métiers2019Activities and societies: Gestion de projet – Linux – Ingénierie logicielle – Réseaux et sécurité des réseaux – Systèmes d’information web Cours suivis à distance en plus de mon travail à Accenture. Anglais: BULAT Score 75 (niveau C1)
Certifications
- BULATCambridge Assessment English2019