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