Job Summary: We are seeking a Senior or Semi-Senior Backend Developer who combines technical excellence, autonomy, and continuous improvement to build robust and scalable systems. Key Highlights: 1. Excellent working atmosphere. 2. Company in expansion. 3. Opportunities for growth. **Description:** ---------------- We are looking for a **Senior or Semi-Senior Backend Developer** with at least **5 years of verifiable experience** developing backend systems using **Node.js, Express, and MongoDB.** **Solid backend experience with Node.js 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 possesses strong backend expertise, writes maintainable code following best practices, and operates comfortably in dynamic environments focused on quality and constant growth. **What We Offer:** * Permanent contract. * Salary commensurate with the position. * Excellent working atmosphere. * Full-time schedule (Monday to Friday). * Company in expansion. * Opportunities for growth. **Requirements:** --------------- **Technical Requirements** **Backend (Mandatory)** * 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.). * Database modeling for both **relational and non-relational systems.** * Experience using **Redis** for caching and session management. * Experience with **RabbitMQ** or other asynchronous messaging systems. * Experience using **Docker** for containerization. * Proficiency in **error handling and logging** in backend applications. * Fluency in using the **bash terminal** and basic **Linux** system administration. **Frontend (Desirable, not mandatory)** * Knowledge of **React** and state management (Redux or Context API). * Understanding of **Hooks** and component lifecycle. * Experience consuming **REST APIs** from the frontend. * Basic knowledge of **SCSS** and CSS architecture. **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). * Prior experience working in full-stack environments (plus).