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I'm Simon Paillassa, a full-stack developer based in Lisbon with 7 years of experience building web and mobile applications. I work mainly with React, Next.js, NestJS and TypeScript, and I'm comfortable taking a project from architecture to deployment. Outside client work I co-founded Ossau, a mobile app for the hiking community, built from scratch and now used by 2,000+ people. French is my native language and English is professional; I also have basic Portuguese.…I'm Simon Paillassa, a full-stack developer based in Lisbon with 7 years of experience building web and mobile applications. I work mainly with React, Next.js, NestJS and TypeScript, and I'm comfortable taking a project from architecture to deployment. Outside client work I co-founded Ossau, a mobile app for the hiking community, built from scratch and now used by 2,000+ people. French is my native language and English is professional; I also have basic Portuguese.

Simon Paillassa

Full Stack Developer, Web Developer, Front-End Developer, +2

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I'm Simon Paillassa, a full-stack developer based in Lisbon with 7 years of experience building web and mobile applications. I work mainly with React, Next.js, NestJS and TypeScript, and I'm comfortable taking a project from architecture to deployment. Outside client work I co-founded Ossau, a mobile app for the hiking community, built from scratch and now used by 2,000+ people. French is my native language and English is professional; I also have basic Portuguese.…I'm Simon Paillassa, a full-stack developer based in Lisbon with 7 years of experience building web and mobile applications. I work mainly with React, Next.js, NestJS and TypeScript, and I'm comfortable taking a project from architecture to deployment. Outside client work I co-founded Ossau, a mobile app for the hiking community, built from scratch and now used by 2,000+ people. French is my native language and English is professional; I also have basic Portuguese.

Available to hire

I’m Simon Paillassa, a full-stack developer based in Lisbon with 7 years of experience building web and mobile applications. I work mainly with React, Next.js, NestJS and TypeScript, and I’m comfortable taking a project from architecture to deployment.

Outside client work I co-founded Ossau, a mobile app for the hiking community, built from scratch and now used by 2,000+ people. French is my native language and English is professional; I also have basic Portuguese.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Language

French

Fluent

English

Advanced

Portuguese

Intermediate

Work Experience

Co-Founder & Lead Developer at Ossau App

June 1, 2025 - Present

Co-founded Ossau, a mobile app for the Pyrénées hiking community, 2,000+ active users. Built the full stack from scratch (NestJS, PostgreSQL, React Native/Expo), handled releases, infrastructure, and automation workflows.

Frontend Developer at Boschung

January 1, 2024 - December 31, 2024

Frontend development on Boschung Web (React/Next.js)

Frontend Developer at STEF

January 1, 2024 - Present

Built a React/Next.js monorepo framework for internal web apps, shared component library, RBAC authorization, centralized admin portal

Full-stack Developer at ADDEO SAS

April 1, 2019 - September 12, 2021

Full-stack developer in an e-learning agency, working on a SaaS career development platform. Rewrote the legacy codebase with clean architecture, improved performance, and worked closely with the design team.