MohamedYessineMaalej

Full Stack EngineerJava / Spring Boot, React / TypeScript

Full Stack Engineer graduated from the National Engineering School of Sfax with 3 years of experience designing and building high-traffic distributed web applications in Java / Spring Boot (backend) and React / TypeScript (frontend). Proven track record in international Agile teams with a strong DevOps culture (Docker, Git, Linux). Designed and operated Orion end to end: a decentralized infrastructure running in production at 97.4% uptime, solar-powered and connected via Starlink.

Orion in production: 97.4% uptime. Each bar is 1/500th of its running time; the short marks are the 2.6% it was down.

Professional experience

March 2024 – PresentRemote (International)

Dione Protocol Orion Project

Full Stack Engineer

Spring Boot 3, React 18, TypeScript 5, Docker

Dione Protocol is an international company specializing in decentralized blockchain data validation through globally distributed nodes.

  • Architected and led development of Orion: a network of 12+ decentralized validators deployed on OrangePi 5 boards, solar-powered and Starlink-connected, sustaining 97.4% uptime in production and replacing cloud infrastructure unavailable in remote areas.
  • Built the Spring Boot 3 node-management backend: OAuth2 / JWT authentication, real-time data streams at <200 ms latency, and REST APIs documented with OpenAPI / Swagger.
  • Developed a monitoring dashboard in React 18 + TypeScript 5: real-time metrics across 12+ nodes concurrently, validator lifecycle management, and threshold-based operational alerting.
  • Engineered a green-energy verification system over MQTT, paired with embedded AI inference models, to certify in real time the renewable origin of the energy consumed by each validator.
September 2023 – February 2024

Future Proof Randev Project

Full Stack Engineer

Spring Boot 3.1, React 18, Redux Toolkit, WebSockets

Future Proof is a SaaS startup building booking and appointment-management solutions for the French-speaking market.

  • Designed Randev, a multi-vertical service booking platform (healthcare, beauty, education) with 3 user roles (admin / provider / client), shipped to staging and production within the first month.
  • Built the Spring Boot 3.1 backend: JWT + Spring Security with fine-grained role-based access control, payment gateway integration, and multi-channel notifications (email / push).
  • Implemented the React 18 + TypeScript 5 frontend with Redux Toolkit for global state (availability, time slots, bookings); reusable components cut UI code by 40% across the three verticals.
  • Delivered real-time synchronization over WebSockets to keep time slots consistent between connected providers and clients, resolving booking conflicts server-side in under 50 ms.
February 2023 – July 2023Sfax, Tunisia

Sofrecom Sfax Orange Group

Full Stack Engineering Intern

React 17, Node.js, Three.js

Sofrecom is the engineering and consulting subsidiary of Orange Group, a global telecommunications operator present in more than 26 countries.

  • Built an interactive 3D e-learning platform in React 17 + Three.js, deployed to production for Orange Group Tunisia employees; optimized WebGL geometries and renderer lifecycle management.
  • Developed the Node.js 18 + Express 4 backend: authentication, learning path management, progress tracking, and REST APIs; MongoDB persistence modeled for non-linear learning paths.
  • Optimized 3D rendering: cut initial load time from ~8s to ~2.5s through asset lazy loading and glTF model compression.

Technical skills

Languages
Java 17, TypeScript 5, JavaScript ES6+, Python 3.11, SQL, Bash
Frameworks
Spring Boot 3.x, React 18, Redux Toolkit, Node.js 20, Express 4, FastAPI
Backend and APIs
REST architecture, WebSockets, Microservices, JWT, OAuth2, Spring Security, MQTT, OpenAPI
DevOps and infrastructure
Docker 25, Linux (Ubuntu 22.04), Git / GitHub
Databases
PostgreSQL, MySQL, MongoDB, Redis
Methodologies
Agile Scrum, TDD, CI/CD, Code Review, JIRA

Education

2019 – 2023
National Engineering School of Sfax (ENIS), University of SfaxNational Engineering Degree (Diplôme d’Ingénieur) in Computer Science, equivalent to M.Sc.Graduated with Highest Distinction and Jury Commendation
2016 – 2019
Preparatory Institute for Engineering Studies of Sfax (IPEIS)Classes Préparatoires, Mathematics–Physics–Computer Science (MPI) track. Admitted through the National Competitive Entrance Examination for Engineering Schools.
2011 – 2015
Lycée Pilote de SfaxHigh School Diploma (Baccalauréat), Mathematics track. Graduated with Distinction.

Languages

Arabic
Native
French
Fluent, C1
English
Full professional proficiency, C1
German
Elementary, A1

Contact

Write to me about a role, a project, or Orion.

yessinemaalej002@gmail.com