Backend Developer

Role summary Position Summary OXUS Afghanistan is seeking an experienced Backend Developer to design, develop, and maintain secure, scalable, and high-performance backend systems that support the organization's digital transformation initiatives. The successful candidate will develop backend applications, build RESTful APIs, integrate databases and third-party services, implement business logic, and collaborate closely with UI/UX Designers, Mobile Application Developers, and other stakeholders to deliver secure, reliable, and enterprise-grade software solutions. Duties and responsibilities Key Responsibilities The Backend Developer will be responsible for the following: Backend Development Design, develop, and maintain secure, scalable, and maintainable backend applications. Develop RESTful APIs for web and mobile applications. Implement business logic based on organizational and business requirements. Write clean, reusable, efficient, and well-documented code. Participate in software architecture and technical design discussions. Database Management Design, develop, and optimize relational databases (Microsoft SQL Server and/or PostgreSQL). Create and maintain database schemas, tables, stored procedures, views, and SQL queries. Optimize database performance through indexing, query optimization, and performance tuning. Ensure database integrity, reliability, backup, and data consistency. API Development & Integration Design and implement secure RESTful APIs following industry best practices. Integrate third-party services such as payment gateways, SMS gateways, email services, authentication providers, and external APIs. Develop and maintain API documentation using standard documentation tools. Ensure proper API versioning and backward compatibility. Security Implement secure authentication and authorization using JWT, OAuth2, or similar technologies. Apply secure coding practices and protect applications against common vulnerabilities, including SQL Injection, Cross-Site Scripting (XSS), Cross-Site Request Forgery (CSRF), and OWASP Top 10 security risks. Implement logging, auditing, and secure handling of sensitive information. Performance & Scalability Optimize application performance, scalability, and reliability. Implement caching mechanisms where appropriate. Develop background processing services for long-running tasks. Monitor application performance and troubleshoot production issues. Collaboration Work closely with UI/UX Designers, Mobile Application Developers, QA, and business stakeholders throughout the software development lifecycle. Participate in code reviews and technical discussions. Contribute to software architecture, design decisions, and continuous improvement initiatives. Documentation Prepare and maintain technical documentation, API documentation, deployment guides, and system documentation. Maintain source code using Git and follow established version control practices. Job requirements Required Qualifications Bachelor's degree in Computer Science, Information Technology, Software Engineering, or a related field. Minimum 3 years of professional experience in backend software development. Experience developing enterprise-level web applications and RESTful APIs. Strong analytical, problem-solving, and communication skills. Ability to work independently and collaboratively within a team. Required Technical Skills Programming & Backend Frameworks Candidates should have strong professional experience with at least one of the following backend technologies: ASP.NET Core (C#) PHP (Laravel) Java (Spring Boot) Python (Django / Django REST Framework) Node.js (Express.js or NestJS) Go (Gin or Fiber) Experience with multiple backend technologies will be considered an advantage. Database Microsoft SQL Server (Required) PostgreSQL or MySQL (Preferred) Database design and normalization SQL query development Stored procedures, views, triggers, and indexing Database performance tuning and optimization API Development RESTful API development JSON HTTP/HTTPS protocols API authentication and authorization API documentation (Swagger/OpenAPI) Authentication & Security JWT Authentication OAuth2 Role-Based Access Control (RBAC) Secure password hashing and session management Knowledge of OWASP security best practices Version Control Git GitHub or GitLab Experience with collaborative development workflows, including branching, pull requests, and code reviews Deployment & Infrastructure IIS, Nginx, or Apache Web Server Windows Server and/or Linux Server administration Docker and containerization (Preferred) CI/CD concepts (Preferred) Additional Technical Skills Experience with the following will be considered an advantage: Background job processing (Celery, Hangfire, Quartz.NET , or similar) Redis or other caching technologies Unit testing and integration testing Debugging and troubleshooting production systems Logging and monitoring tools Third-party API integrations Agile/Scrum development methodologies Preferred Competencies Strong understanding of software architecture and design patterns. Knowledge of database optimization and performance tuning. Ability to develop secure, scalable, and maintainable enterprise applications. Strong problem-solving and analytical skills. Excellent communication and teamwork abilities. Ability to work under pressure and meet project deadlines. Commitment to continuous learning and adopting new technologies.