Top Senior Java Developer Jobs in NYC, NY

Lead design and delivery of high-throughput, fault-tolerant backend systems for Aladdin. Build microservices, streaming architectures, and distributed applications; collaborate with product and global teams; apply test-driven development, perform code reviews, and provide production support while mentoring engineers and driving technical roadmap.

As a Senior Software Engineer at Squarespace, you will build scalable backend services, write clean and efficient code, and contribute to architecture discussions while collaborating with cross-functional teams.

The role involves building trading solutions using Java, working with traders, managing projects, and ensuring compliance with standards.

Design, build, and optimize Windchill Java customizations (services, listeners, processors, TAM types, JSP/HTML UI). Lead migrations, troubleshoot production issues, document architecture, and mentor engineers while ensuring upgrade-friendly, high-performance PTC customizations.

Develop and maintain trading applications, resolve complex issues, collaborate with global teams, and lead project implementations in an agile environment.

Design, implement, and evolve scalable Java backend services powering Squarespace's Email product. Lead architecture and system design, build RESTful APIs, ensure reliability and observability, mentor engineers, troubleshoot production incidents, participate in on-call rotations, and collaborate cross-functionally to deliver customer-facing email capabilities.

The Lead Java Developer will design, build, and operate large-scale trading platforms, focusing on low latency and cloud services. Responsibilities include development support, process automation, and team collaboration.

Contract Java Developer (12-16 month contract) to develop and maintain applications using GWT, Java and J2EE. Must have GWT expertise; Spring, Hibernate and SQL are desirable. Located in New York; requires 5+ years of relevant experience.

Develop and implement J2EE web applications using Java and Spring on WebSphere. Participate in full lifecycle: requirements, design, coding, testing, performance tuning, deployment, production support, and mentor junior developers.

Develop and maintain Java middleware applications using Spring and Struts. Implement Spring Integration and RESTful services, build web UIs with JavaScript/jQuery/HTML/CSS, perform SQL work with MS SQL/Oracle, participate in design/architecture reviews, SDLC and project lifecycle activities, and work within financial services in a global delivery environment.

Lead and develop enterprise Java applications in a WebSphere environment. Design and build REST/SOAP services, ensure thread-safe concurrency, tune high-volume systems, use J2EE/Spring frameworks and ORMs, work in Agile teams, write automated tests, integrate with MQ and databases, and mentor a small development team.

Hiring 18 Java developers for three on-site locations (NY, Chicago, Dowingtown PA). Candidates must have 6-8 years Java experience, SCJP certification, and strong skills in Oracle, UML/design, Hibernate, Spring, Servlets, Struts, and front-end technologies (JavaScript/HTML/CSS/AJAX).

The Technical Lead Java Developer will oversee development, ensure coding standards, coach junior developers, and manage project delivery while working on complex enterprise projects.

Design, develop, and maintain high-performance, secure Java backend services and APIs. Ensure reliability, scalability, and cost-efficiency across microservices, databases, messaging systems, and capacity planning. Troubleshoot, profile, benchmark, and optimize systems (including ML applications) and collaborate with Kazakhstan stakeholders.

Reverse-engineer TIBCO BW/MFT processes to extract business logic, then design and implement a modular Java/Spring Boot microservices replacement. Migrate protocols to Kafka/RabbitMQ/REST, translate XML transformations, ensure data persistence and consistency, and validate performance to meet existing SLAs.

Design, build, and maintain Java/J2EE multi-layer applications and APIs. Collaborate with architects and DevOps to implement CI/CD, code quality, testing, and database solutions (DB2/Oracle, PL/SQL). Support cross-team delivery, resolve technical roadblocks, and drive process improvements in an asset management/financial services context.

Analyze legacy TIBCO BusinessWorks/MFT processes to extract business logic, design and build a decoupled Java/Spring Boot microservices platform, migrate protocols to Kafka/RabbitMQ/REST, translate XML-heavy transformations to modern formats, and validate performance and SLAs to match legacy throughput.

The role focuses on delivering technical solutions within the Trading application, involving Java development, problem-solving, and managing project delivery with global teams.

Design, develop, test, and deploy Java/J2EE applications and integrations. Lead implementation planning, gather and specify requirements, mentor junior developers, resolve defects, support production (on-call), and ensure database and SOX-compliant process documentation.

Lead the evolution of a fraud screening platform by integrating Generative AI and machine learning, mentoring teams, and driving solutions in an Agile environment.

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.

Seeking an experienced Java Backend Engineer to design, develop, and maintain backend systems and APIs using modern Java technologies.

The role involves designing and implementing FXall's Trading System User Interface using Java/Swing, focusing on system design, multi-threading, and collaboration with traders.

The Lead Software Engineer will lead technology projects, develop cloud-based solutions, and work with a team to create a messaging platform for Capital One Travel products.

Lead migration of legacy COBOL systems to Java-based microservices and develop scalable, secure full-stack solutions on Azure. Build RESTful APIs, optimize performance, ensure DoD cybersecurity compliance, collaborate across teams, document architectures, and participate in Agile ceremonies.