Top Senior Java Developer Jobs in Buffalo, NY

Lead architecture and delivery of large-scale microservices systems, define standards and roadmaps, mentor engineers, ensure scalability/resilience, oversee CI/CD, observability, data strategy, and cross-functional technical alignment.

Design, develop, and maintain high-performance Java microservices using Spring Boot. Implement threading/concurrency, fault-tolerance (Hystrix/circuit breakers), observability (SLI/SLO), and event-driven solutions with Kafka. Deploy and operate services on Kubernetes and AWS, mentor junior developers, and collaborate with cross-functional teams to deliver reliable, scalable features.

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 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.

Lead design and delivery of scalable, resilient distributed systems. Act as technical authority across teams, mentor engineers, drive architecture and CI/CD best practices, troubleshoot production issues, optimize performance, and enhance observability while writing production-grade Java.

Remote Senior Java Developer responsible for building Java web applications using JSP and Struts2/MVC, creating reports with Jasper or SSRS, and managing Linux application servers (load balancers, JBoss, Apache, WildFly).

Senior Java Engineer responsible for designing and delivering high-quality, low-maintenance software. Coach client teams on modern development practices, apply test-driven development, collaborate in small teams, and pursue continuous learning to improve scalable, maintainable applications.

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.

Design, build, and maintain scalable, highly available backend services in Java. Own backend architecture, optimize performance, develop APIs and integrations, support production, conduct code reviews, and contribute to AI engineering tools and infrastructure.

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.

The Senior Full Stack Java Developer will design and maintain enterprise applications using Java and modern front-end technologies while collaborating in Agile teams and mentoring junior developers.

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.

Design, implement, test, and maintain scalable Java/J2EE microservices using Spring technologies. Collaborate with architects, follow SDLC, perform unit/system testing, troubleshoot distributed cloud applications, and work in Agile teams to meet enterprise performance and security standards.

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.

As a Senior Software Engineer, you will maintain and develop data connectors, enhance data integrations, and improve developer experience within the ClickHouse data ecosystem.

The Senior Java Developer will design, develop, and implement custom software solutions in Agile teams, mentor juniors, and ensure product quality.

Senior Java engineer delivering AI-augmented production features and modernizations across a Java/Python/AWS stack. Pair with engineers to embed agentic practices, own systems end-to-end, participate in AI-augmented reviews, and judge agent use versus human intervention.

Senior Java engineer delivering AI-augmented production features and modernizations across a Java/Python/AWS stack. Own systems end-to-end, pair with engineers to transfer agentic practices, perform AI-augmented code reviews, and judge when to trust or intervene with agent outputs.