Job Summary: We are seeking a Senior or Semi-Senior Full Stack Developer to build robust, scalable, and high-performance systems, combining technical excellence with autonomy. Key Highlights: 1. Excellent work environment 2. Growing company 3. Opportunities for growth **Description:** ---------------- We are looking for a Senior or Semi-Senior Full Stack Developer with at least 5 years of proven experience developing modern applications using the MERN stack (MongoDB, Express, React, Node.js). Proven MERN experience is mandatory. We seek a candidate who combines technical excellence, autonomy, and a mindset of continuous improvement, and who enjoys building robust, scalable, and high-performance systems. The ideal candidate masters MERN stack tools, writes maintainable code following best practices, and operates comfortably in dynamic environments focused on quality and constant growth. What do we offer? * Permanent contract. * Salary commensurate with the position. * Excellent work environment. * Full-time schedule (Monday to Friday). * Growing company. * Opportunities for growth. **Requirements:** --------------- **Technical Requirements** Frontend * Advanced experience with React and solid handling of global state with Redux. * Proficiency in using Hooks and understanding React component lifecycle. * Strong command of JavaScript ES6\+ and understanding of asynchrony (Promises, async/await, event loop). * Solid knowledge of SCSS, including modular architecture and BEM principles. * Experience consuming and managing REST APIs. * Experience with real-time communication via Socket.IO. * Experience with internationalization (i18n) using react\-i18next (preferred). * Experience configuring and optimizing Webpack. * Experience with automated testing using Jest (unit and integration tests). * Proper handling of loading, error, and empty states in interfaces. Backend * Advanced experience with Node.js and Express. * Data validation and sanitization, and prevention of common vulnerabilities (XSS, CSRF, etc.). * Implementation of authentication and authorization with JWT. * Solid knowledge of MongoDB and Mongoose. * Creation and optimization of complex MongoDB queries (Aggregation Framework, lookups, pipelines, etc.). * Modeling of relational and non-relational databases. * Experience using Redis for caching and session management. * Experience with RabbitMQ or other asynchronous messaging systems. * Experience using Docker for containerization. * Good error handling and logging in backend applications. * Proficiency in bash terminal usage and basic Linux system administration. **Environment and Tools** * Experience working with Jira and agile methodologies, especially Scrum. * Ability to understand and write clear, structured technical documentation. * Knowledge of Git and CI/CD workflows. **We Value** * Application of KISS, DRY, and SOLID principles. * Ability to analyze and optimize code. * Initiative, responsibility, and attention to detail. * Prior experience with high-traffic systems or distributed architectures (plus).