Backend
11APIs, data and the services between them.
- Node.js
- TypeScript
- Java
- Spring Boot
- PostgreSQL
- MongoDB
- Redis
- REST APIs
- GraphQL
- Microservices
- JWT
Chadjaa.
Sofiane Chadjaa.
Full-stack engineer building payment platforms, IoT device control and SaaS products.
01Stack
The whole stack, end to end.
33 tools I reach for, grouped by the part of a product they serve.
Frontend
05Interfaces that stay clear as products grow.
- React
- Next.js
- Tailwind CSS
- Redux Toolkit
- Webpack
Infrastructure
12Shipping, running and watching it in production.
- Docker
- Kubernetes
- Nginx
- CI/CD
- GitHub Actions
- Jenkins
- Linux
- Git
- Prometheus
- Grafana
- Keycloak
- MQTT
AI & agents
05Models wired into real product workflows.
- LLM APIs
- RAG Pipelines
- LangChain
- Prompt Eng.
- Automation
02Experience
Shipping to production since 2020.
Payments, IoT device control and internal platforms, most of it under NDA. Open a role for the systems and decisions behind it.
03About
Calm engineering for high-stakes products.
What I do
Full-stack development for fintech, real-time products and high-reliability systems: work where mistakes are expensive.
How I work
Async-first, thorough in discovery, and comfortable flying solo or partnering with design. Most production work is under NDA, including payment platforms, IoT device control, and internal tools at scale.
What I'm looking for
Freelance and contract projects, especially new builds or scale-ups that need to be done right from day one.
Available for freelance & contract work
Have something that needs to be done right?