Top Senior Java Developer Jobs in Denver & Boulder, CO

Design, develop, and maintain scalable Java backend services and RESTful APIs. Collaborate with frontend, product, and stakeholders; write clean, tested code; troubleshoot and resolve issues; participate in code reviews; and improve systems, particularly for large-scale distributed environments.

Design, implement, and maintain Java-based applications to automate financial data reconciliation across relational and NoSQL sources. Build deterministic and heuristic matching algorithms, integrate with rules engines (Drools), handle errors and exceptions, collaborate with analysts and architects to resolve data gaps, and support data governance and quality initiatives.

Design, implement, and maintain Java-based applications to automate complex data reconciliation across relational and NoSQL sources. Build matching algorithms, integrate with rules engines (Drools), handle data streams, perform gap analysis, and collaborate with analysts and architects to ensure data quality.

Design, develop, and maintain high-performance Java applications and microservices on an Agile team. Implement RESTful APIs, integrate with SQL/NoSQL databases, use Git-based version control, and follow SDLC and peer-review processes. Support program deliveries, work on 2-week sprints, and coordinate with cross-functional teams. Requires active Top Secret clearance and occasional travel (~10%).

Design, develop, and modernize software by translating legacy mainframe code (COBOL/ASM/JCL/Copybooks) into Java microservices. Support UI integration, relational and hierarchical databases, batch and real-time processing, CI/CD, cloud-native and ZT/ICAM integration, and use AI/ML tools to assist translation and optimization. Work supports pre-production, testing, and integration activities.

Develop and maintain Java Spring Boot microservices, write automated tests and API validations, debug and optimize performance, collaborate with architects, front-end developers and product owners, participate in Agile ceremonies, document designs, perform peer code reviews, and support deployments and release activities.

Develop and maintain core Elasticsearch infrastructure and shared platform features. Design scalable APIs, solve performance and concurrency issues, improve observability and CI/CD, automate developer workflows, lead cross-team projects, support complex operational investigations, and use AI to accelerate development and debugging.

Design, build, and improve Elasticsearch distributed-systems components for scalable, concurrent, and consistent indexing. Maintain cluster coordination for performance and resilience, push system scale limits, investigate performance and concurrency issues, support operations/support engineers, and lead projects involving multiple engineers from design through delivery.

The role involves improving Elasticsearch's distributed components, maintaining cluster coordination systems, and addressing complex issues to optimize performance and scalability.

The Sr Software Developer will design, develop, and mentor direct reports in software for the real estate industry, solving complex problems and ensuring product functionality and performance.

The Staff Engineer will leverage over 5 years of experience in Java, JavaScript, and frameworks to develop robust solutions, mentor teammates, and enhance client outcomes while utilizing agile methodologies and cloud development tools.

Seeking a Staff Engineer with 5+ years in Java, focusing on mentoring teammates, solving client challenges, and conducting cloud development.

Senior Java engineer responsible for designing, developing, and maintaining scalable, secure backend systems using Java and modern frameworks. Participate in architecture, collaborate with product and security teams, write maintainable code, and adopt AI-assisted development tools while contributing to open-source efforts.

Lead Java developer responsible for designing and developing web applications, administering Drupal and Mulesoft integrations, producing architecture/design documents, troubleshooting performance, gathering requirements, and leading technical resources. Strong frontend and full-stack web skills and experience with development methodologies required.

Maintain and enhance U.S. Bank's Customer Information System and Hogan platforms. Design, develop, test, and operate mainframe services/APIs, diagnose and resolve incidents, perform code reviews, ensure security/compliance, collaborate with business and cross-functional teams, mentor peers, and participate in Scrum-driven delivery.

Design, develop, test and maintain Java/J2EE web applications and backend services using Spring, Hibernate, messaging and RDBMS. Participate in requirements analysis, architecture and Agile ceremonies, write SQL and stored procedures, build/deploy with ANT/Maven, and use testing and CI tools to ensure high-quality deliverables.

Design, develop, test and maintain enterprise Java/J2EE web applications using Spring, Hibernate and related frameworks. Work across SDLC in Agile/Waterfall, implement front-end components (Angular/Bootstrap), integrate messaging (JMS/MQ) and databases (Oracle/SQL Server/MySQL), use build and CI tools, and participate in estimation, code reviews and deployment.

Senior Java ATG developer responsible for full-stack development using ATG, Java/J2EE, web services, front-end technologies, and frameworks. Work includes database integration with Oracle/JDBC/PL-SQL, microservices and messaging (RabbitMQ), cloud (AWS), iOS/Swift exposure, participating across the SDLC, debugging, and collaborating with stakeholders and cross-functional teams.

Senior Java Developer responsible for designing, implementing, and testing Java/J2EE web applications using Spring, Hibernate, JMS/MQ, and SQL. Work includes front-end integration (Angular/Bootstrap), application server deployment, database development, unit and integration testing, and participating in Agile ceremonies and design sessions.

Develop and maintain enterprise-class Java backend software for centralized management of hyperconverged data center products. Collaborate with cross-functional teams in an Agile/Scrum environment, integrate core product components, work with VMware and cloud automation tooling, and drive software design, quality, and supportability.

Senior individual-contributor backend engineer responsible for designing, building, and operating production-grade, highly available, strongly consistent services for wallet operations, transaction orchestration, blockchain integrations, and event-driven workflows. Implement secure, scalable APIs, cryptographic key management, Kafka-based event systems, observability with OpenTelemetry, CI/CD pipelines, and produce tests, API specs, and operational runbooks.

Develop and operate Java Spring Boot microservices, deploy and manage services on Kubernetes, perform JVM profiling and heap analysis, load test, diagnose memory leaks, OOMs and P99 latency spikes, remediate security vulnerabilities, and maintain GitHub-based CI/CD and branching workflows.

Design and develop a high-volume, distributed multi-tenant Java platform. Build and deploy Java/Scala services with RESTful APIs in a Big Data environment, focusing on low-latency, concurrency, relational database integration, test-first development, and Agile practices.

Develop and maintain Java/J2EE enterprise applications using Spring, Hibernate, Web Services, and Oracle/PL-SQL. Participate in design/architecture reviews, requirements elicitation, and SDLC activities. Work with CI tools, version control, and QA processes in a financial services global delivery environment.

Senior Java developer responsible for designing, developing, and deploying Java/J2EE web applications and microservices. Work includes SOAP/REST web services, CI/CD, Tomcat/WebLogic deployments, JDBC/Hibernate/iBatis integration, performance tuning, and supporting assessment/design/code/build/deploy phases, primarily for US cable MSO IT systems.