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# Senior Software Engineer - Java API Developer

- **Company:** PubMatic
- **Location:** United States (Remote available)
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** Java (Programming Language), Application Programming Interfaces (APIs), Agile Methodology, Artificial Intelligence, Data Analysis, Big Data, Software Quality, Code Review, Continuous Integration, Data Structures, Database Queries, DevOps, Java Platform Enterprise Edition (J2EE), Hibernate (Java), Spring Framework, Junit, Python (Programming Language), PostgreSQL, Machine Learning, Apache Maven, MySQL, OAuth, Object-Oriented Software Development, Performance Tuning, Systems Development Life Cycle, Recommender Systems, Azure Machine Learning, Software Engineering, SQL Databases, Data Logging, Test-Driven Development (TDD), Retrieval-Augmented Generation, Large Language Models, Prompt Engineering, Spring-boot, Software Security, Indexer, Backend, Agentic-AI, Git, Kubernetes, Restful APIs, Code Restructuring, Docker, Jenkins, Microservices
- **Published:** November 9, 2026
- **Apply:** https://www.careerbuilder.com/job-details/senior-software-engineer-java-api-developer-south-bend-in--a1672b0a-c497-4cd6-941c-54561887baee

## About the Role

Software Engineering, Application Programming Interface (API), Java, Application Programming Interface (API), Java, Software Engineering, Advertising, Scalable System Development, Machine Learning, Mobile Advertising, * 3-6 years of experience in Java development in Linux/UNIX environments.

 * Strong proficiency in Core Java, OOPS, Data Structures, and J2EE technologies.
 * Hands-on experience with Spring, Spring Boot, and Hibernate.
 * Strong experience in REST Web Services development and microservices architecture.
 * Proficiency in SQL, schema design, indexing, performance tuning, and complex queries.
 * Experience with Docker, Kubernetes, Jenkins, Maven, Git, and CI/CD pipelines.
 * Experience working on high-performance and scalable AdTech systems (preferred).
 * Working knowledge of Python and integration with AI/ML services.
 * Understanding of advanced AI concepts including RAG, agentic AI, model fine-tuning, and recommendation systems.
 * Experience in JUnit, TDD, refactoring, and Agile development practices.
 * Demonstrated ability to work independently and drive technical ownership.

Qualification:

Should have a bachelor's degree in engineering or an equivalent degree from a well-known institute/university.

## Description

We are seeking a highly skilled Senior Java API developer with experience in building high-performing, scalable, enterprise-grade backend systems in the digital advertising domain.

In this role, you will design, develop, and optimize backend services powering Mobile Ad SDK systems and AI-driven products such as recommendation engines, monetization optimization platforms, and intelligent ad delivery systems. This role will be responsible for productionizing machine learning models, building high-performance APIs, and enabling intelligent decision systems at scale

What You'll Do:

 * Design and develop scalable, secure, and high-performance RESTful APIs using Java (Java 11+) and Spring Boot.
 * Own end-to-end solution design, planning, execution, and release of backend features.
 * Build and maintain backend services supporting AI-driven initiatives (recommendation systems, predictive analytics).
 * Productionize and integrate ML models into backend systems, enabling real-time intelligent decisioning.
 * Develop efficient data models and optimize database queries (MySQL/PostgreSQL) for performance and reliability.
 * Ensure API security using OAuth2, JWT, and role-based access controls.
 * Build for scale-design systems capable of handling high concurrency, large data volumes, and low-latency requirements.
 * Implement observability best practices including logging, monitoring, tracing, and alerting.
 * Participate in code reviews, design discussions, and technical decision-making to ensure engineering excellence.
 * Collaborate cross-functionally with Analytics, Product, SDK, UI, Ad server, DevOps, and QA teams to deliver AI-powered features.
 * Leverage generative AI tools and advanced prompt engineering techniques to enhance productivity and code quality.