Celoxis- Medior Backend Java Developer

Medior Backend Java Developer

About the Project

• Join our team and work on a mature, feature-rich Project & Service Automation (PSA)
• platform, an enterprise-grade solution that powers project management, resource planning,
• time tracking, expense management, and business reporting for global customers. Our
• platform supports multi-tenant environments with complex business workflows, and we are
• actively expanding its capabilities with advanced AI/ML features.

Key Responsibilities

• ● Design and implement RESTful APIs following established architectural pattern
• ● Develop and maintain backend features for project management, resource allocation,
• time tracking, and expense management modules.
• ● Participate in AI/ML feature development using LangChain4j and Spring AI
• frameworks
• ● Work with ORM to build complex database queries and optimize data access layers
• ● Implement business logic for approval workflows and process automation
• ● Integrate third-party services (accounting systems, CRM platforms, authentication
• providers)
• ● Develop scheduled background, data synchronization, and forecasting
• ● Ensure proper security implementation through ACL and role based access control

Required Technical Skills

Technologies & Frameworks

• ● Backend: Spring Boot 3.x, Spring MVC, Spring AOP, Spring WebSocket
• ● ORM: Apache Torque with Criteria-based query building
• ● Database: PostgreSQL with pgvector for AI embeddings
• ● Security: OneLogin SAML, Google Authenticator, jBCrypt
• ● Integrations: QuickBooks SDK, Zapier, Google services, MPXJ

Architecture & Design Patterns

• ● Service Layer Pattern and Repository Pattern
• ● Singleton, Factory, and Decorator patterns
• ● Event-driven architecture (pub/sub, event listeners)
• ● Multi-layered architecture design
• ● Understanding of domain-driven design principles

Database & Data Management

• ● PostgreSQL or similar relational databases
• ● Transaction management and data integrity
• ● Query optimization and performance tuning
• ● Database migration and schema management
• ● Experience with Criteria based query builder

Experience Level

5+ years of professional Java backend development experience with

• ● At least 2 years working with Spring Framework
• ● Experience with enterprise-level applications
• ● Understanding of multi-tenant architectures (preferred)
• ● Exposure to project management or ERP systems (nice to have)

Soft Skills & Work Approach

• ● Problem Solving: Ability to navigate and understand large, complex codebases
• ● Code Quality: Writing maintainable, well structured code following established
• patterns
• ● Collaboration: Working with cross-functional teams (frontend, QA, product)
• ● Documentation: Creating clear technical documentation and code comments
• ● Learning Agility: Quickly understanding new domains and technologies
• ● Attention to Detail: Ensuring data integrity and business rule compliance in complex
• workflows

Desired Technical Skills

• ● Frontend Basics: Understanding of React and REST API consumption patterns
• ● Integration Experience: Webhooks, third-party API integration (QuickBooks, Zapier,
• etc.)
• ● Background Processing: Quartz scheduler or similar job scheduling frameworks
• ● Reporting Engines: Experience with data visualization and reporting libraries
• ● AI/ML Integration: LangChain4j, Spring AI, or similar AI frameworks
• Why This Role is Interesting
• ● Complex Domain: Work on sophisticated business logic
• ● Architecture: Learn advanced patterns in multi-tenancy, event-driven design, and
• extensible systems
• ● Modern Tech: Actively integrating AI/ML capabilities into production
• ● Scale: Navigate and contribute to a large, mature codebase with established
• patterns
• ● Impact: Your work directly affects project management workflows for enterprise
• clients\
• ● Growth: Exposure to diverse technical challenges from scheduling algorithms to AI
• integration