Backend Java Developer - Contract

Position Overview
We are seeking a talented Backend Java Developer to design, develop, and maintain scalable backend systems and APIs. In this role, you will build high-performance services, integrate with databases and external systems, and ensure reliability, security, and code quality through comprehensive testing and industry best practices.

Key Responsibilities

System Design & Development

. Design and develop scalable, high-performance backend systems and microservices

. Build and maintain RESTful APIs for seamless integration with frontend and external systems

. Implement robust, maintainable code following object-oriented programming principles

. Apply appropriate design patterns to solve complex technical challenges

Integration & Data Management

. Integrate backend services with relational databases (MySQL, PostgreSQL) and/or NoSQL databases (MongoDB)

. Design and optimize database schemas and queries for performance

. Work with external APIs and third-party services

. Implement data validation, transformation, and processing logic

Architecture & Best Practices

. Develop microservices following distributed architecture patterns

. Ensure system reliability, scalability, and fault tolerance

. Implement API security measures including authentication and authorization

. Follow coding standards and best practices for maintainable, clean code

Quality Assurance & Testing

. Write comprehensive unit tests using JUnit and Mockito

. Participate in code reviews to maintain code quality

. Debug and troubleshoot production issues

. Implement integration and end-to-end tests where appropriate

DevOps & Deployment

. Work with CI/CD pipelines to automate build and deployment processes

. Utilize build tools such as Maven or Gradle

. Collaborate with DevOps teams on deployment strategies

. Monitor application performance and implement improvements

Required Qualifications

Experience

. Minimum 3 years of professional experience in backend development

Core Technologies:

. Strong proficiency in Java with deep knowledge of the ecosystem

. Expertise in Spring Framework and Spring Boot

. Hands-on experience building and deploying microservices

API Development:

. Proven experience building RESTful APIs and backend services

. Understanding of API design principles and best practices

. Knowledge of API documentation standards (Swagger/OpenAPI is a plus)

Fundamentals:

. Solid understanding of Object-Oriented Programming (OOP) principles

. Strong knowledge of data structures and algorithms

. Practical application of design patterns (Singleton, Factory, Strategy, etc.)

Database:

. Experience with relational databases (MySQL, PostgreSQL)

. Knowledge of NoSQL databases (MongoDB) is highly valued

. Understanding of database design, indexing, and query optimization

Architecture:

. Knowledge of microservices architecture patterns

. Understanding of distributed systems concepts

. Familiarity with service discovery, API gateways, and inter-service communication

Security:

. Understanding of API security best practices

. Experience implementing authentication mechanisms (JWT, OAuth2)

. Knowledge of authorization patterns and role-based access control

Development Tools:

. Proficiency with version control using Git

. Experience with testing frameworks (JUnit, Mockito)

. Familiarity with build tools (Maven/Gradle)

. Basic knowledge of CI/CD pipelines (Jenkins, GitLab CI, GitHub Actions, etc.)