Nonprofit
Senior Fullstack Developer (React/Next.js/Node.js) for a solidarity association
Details
Description
Mission offered byKarma Com Soliderité throughout the Hauts-de-Seine department
Join our mission for digital solidarity
Mission offered by Karma Com Solidarity throughout France
Are you passionate about modern web development and do you want your code to serve a purpose that truly matters?
At Karma Com Solidarité (KCS), we build platforms that concretely help associations to better manage their projects, their volunteers, their communication.
No more empty talk: every feature you deploy means an organization saves time, increases efficiency, and has a greater impact. And that's measurable!
About Karma Com Solidarity
Karma Com Solidarité is an association that strengthens the impact of non-profit organizations through responsible communication and digital inclusion. We code for those who don't have the resources of an IT department, we train those who need it, and we create game-changing tools.
Guided by values of solidarity, inclusion and transparency , we welcome senior and junior tech profiles (depending on the missions) who want to put their expertise at the service of the common good.
Your mission, should you choose to accept it!
As a senior full-stack developer volunteer , you will be the technical lead for our web ecosystem (institutional websites + SaaS platforms for associations). You will code in React/Next.js , develop backend APIs in Node.js , coordinate with our DevOps team, and ensure that our applications are high-performing, accessible, and deployed properly.
In this role, you will contribute your expertise to:
- Develop modern full-stack applications : Next.js (App Router, Server Components, Server Actions), React with TypeScript, state management (Redux Toolkit, Context API)
- Design and maintain backend APIs : Node.js with Express/Fastify, PostgreSQL/MongoDB/Redis databases, REST and GraphQL APIs (Apollo/Prisma)
- Implementing authentication and security : JWT, OAuth, NextAuth, security best practices (vulnerability scans)
- Setting up CI/CD pipelines : GitHub Actions/GitLab CI, build/deployment automation, environment management (dev/staging/prod)
- Containerizing and deploying : Docker, Docker Compose, cloud deployments (AWS EC2/S3/RDS, Vercel, Heroku)
- Ensuring quality and performance : automated testing (Jest, React Testing Library), Core Web Vitals optimization, monitoring
- Maintaining clean and well-documented code : Git conventions (GitFlow, commits), constructive code reviews, clear technical documentation
Why join KCS?
Direct social impact
Your code will be used by 15-20 organizations starting in 2026-2027 to manage their volunteers, projects, and communications. Every line you write tangibly improves digital inclusion and the efficiency of organizations that change lives. We measure the impact, we see it, we celebrate it.
Structured & professional environment
We work with robust tools (GitHub, Figma, Notion, Slack, Docker, CI/CD), clear processes (kickoff, Definition of Done, regular reviews), and an expert team that supports you without micromanaging you. You'll have technical autonomy, but you'll never feel like you're alone against a wall.
Professional Development
Access to training relevant to the mission, technical exchanges with senior peers, and a portfolio of potentially open-source projects (depending on negotiated licenses). And if you'd like a LinkedIn recommendation after 12 months of impeccable service, we'd be happy to provide it.
Freedom and recognition
You have complete freedom in making technical choices (within the overall architectural framework), your ideas matter, and your work is valued. We don't count the hours down to the minute, we count the results and the impact. And we say thank you when it's done well.
Kindly do apply with your updated resume to make the process fast.
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You will never be alone on this adventure
The KCS team will support you throughout your mission, through:
- Regular meetings with your designated contact person (IT & Tech department)
- A structured kickoff to set objectives, DoD (Definition of Done), and work pace
- Ongoing support via Slack (asynchronous) + video calls if needed
- Clear documentation and professional tools to facilitate your integration
Our way of working
DO (what works for us):
- Clarity & reliability : We say things as they are, we keep our promises, we alert early if necessary (no "everything's fine" then ghosting for 3 weeks)
- Traceability : Decisions and deliverables on official tools (GitHub, Notion, Drive), not "in a personal Slack DM"
- Structured collaboration : Regular check-ins, clear objectives (DoD = Definition of Done), constructive feedback
- Supported autonomy : You manage your time, we support you when needed, and we celebrate collective victories.
DON'T (what to avoid):
- Working in silos without communicating progress (we like to know where you are, even if it's "I struggled but I learned something")
- Keep all deliverables on your personal machine only (code/sources on GitHub/KCS Drive, always)
- Take responsibility alone without asking for help if you get stuck (we prefer a quick "help" to a silent burnout)
- Making commitments without verifying one's actual availability (it's better to say "I can do 4 hours this week" than to promise 8 hours and deliver 0)
