Top Senior Java Developer Jobs in NYC, NY

Lead development of scalable Java software applications and high-availability services. Design architectures, solve complex system challenges, improve performance and scalability, and maintain quality standards. Collaborate cross-functionally, mentor junior engineers, own technical initiatives, address support-driven issues, and implement robust testing practices for mission-critical IT operations products.

Design, develop, and enhance scalable Java software for NinjaOne’s IT Operations platform. Lead architectural decisions, build high-availability services, address scalability and technical debt, improve quality practices, collaborate across teams, mentor engineers, and own technical initiatives supporting millions of endpoints and servers.

Lead development of scalable Java applications and high-availability services. Design system architecture, solve complex scalability challenges, improve quality, mentor engineers, collaborate cross-functionally, and own technical initiatives supporting a global IT operations platform.

Lead development of full-stack cloud-native applications using Java, TypeScript, Spring Boot, Spring Cloud, and AWS. Responsibilities include designing microservices, APIs, agentic workflows, reactive systems, infrastructure as code, CI/CD, observability, databases, and performance testing. The role also leads responsible adoption of AI-assisted engineering tools, coaches teams on secure validation practices, and troubleshoots multi-agent environments.

Develop and scale backend Java and Kotlin software powering patch discovery, packaging, and deployment across millions of endpoints. Design scalable systems, APIs, data structures, caching solutions, and relational databases while maintaining high testing and code-quality standards. Collaborate with AI workflow, server, platform, design, and product teams. Occasional React or Angular work may support patching workflows and dashboards.

Lead full‑stack development for hedge fund technology: gather requirements, design and implement Java/Python/React applications, support AWS/Terraform infrastructure and RDS databases, drive AI‑assisted engineering practices, mentor engineers, integrate third‑party vendor systems, and ensure secure, scalable, test‑driven delivery.

Lead development of scalable Java backend applications and high-availability cloud services. Design architectures, REST APIs, databases, caching systems, and distributed session infrastructure. Mentor engineers, drive technical initiatives, address performance and scalability challenges, and uphold quality and automation practices for endpoint management products.

Lead software engineering for secure, scalable, production-grade applications in an agile enterprise environment. Design complex solutions and architecture, develop Java microservices and REST APIs, improve reliability through automated testing and CI/CD, analyze system data, and build reusable components. Guide responsible adoption of AI-assisted engineering tools, coach team members on secure validation practices, troubleshoot complex issues, and deliver high-throughput distributed systems across cloud-native platforms.

Develop backend applications and microservices for a large-scale deposits platform. Build and maintain Java and Spring Boot services, implement distributed processing with Kafka, and deploy within cloud environments such as AWS or GCP. Participate in coding interviews requiring screen sharing, work a five-day schedule, provide on-call support every eight weeks, and assist with occasional evening production deployments.

Lead development of scalable platform software supporting BlackRock’s Aladdin investment operating system. Responsibilities include building Java systems, CI/CD pipelines, container platforms, distributed services, data and messaging capabilities, and highly available applications. The role provides technical leadership, manages project priorities, applies test-driven and Agile practices, supports production operations, collaborates on roadmaps, and contributes to recruiting and team culture.

Design, build, and optimize high-performance, low-latency Java services and protocols for exchange and matching-engine systems. The role includes modeling orders and accounts, developing automated testing and benchmarking strategies, profiling performance, diagnosing production issues, collaborating with clients and internal engineering teams, and supporting deployments. After six months, the engineer will independently own technical workstreams through production readiness while delivering observable, maintainable systems and communicating technical trade-offs effectively.

Lead backend architecture and implementation for Citi's FX eCommerce trading platform. Build high-performance, multithreaded Java services, integrate with product teams, resolve complex system issues, coach mid-level developers, and ensure resilient, low-latency, production-ready solutions that meet regulatory and risk standards.

Develop scalable, resilient, and secure backend services using Java, Spring Boot, microservices, and REST APIs. Build and document integrations, deploy containerized applications on Azure or AWS, optimize relational database queries, and participate in Agile Scrum ceremonies, code reviews, automated testing, and cross-functional collaboration with product, QA, and architecture teams. Monthly travel to Vienna, Virginia may be required.

Build enterprise Workforce Management software using Java, Spring Boot, React, TypeScript, and Node.js. Responsibilities include developing microservices, REST APIs, event-driven workflows, scheduling and forecasting capabilities, integrations with CX and enterprise systems, PostgreSQL data models, cloud-native deployments, CI/CD pipelines, and production performance improvements. Collaborate with cross-functional stakeholders on architecture, design, testing, and delivery.

Leads the architecture, development, and delivery of a global equity derivatives pricing platform and RFQ workflow. Develops Java server and C# client features, designs REST-based solutions, maintains automated test suites, improves CI/CD pipelines, and supports deployment strategies. The role includes requirements refinement, architecture planning, proof-of-concepts, agile delivery, compliance, mentoring engineers, and collaboration with business and platform partners.

Hands-on senior engineer responsible for designing, building, and operating a multi-threaded, Linux-based, real-time Java platform for Equity Swaps. Drive architecture, mentor engineers, own core components (including cashflow calculator), operate and tune sharded MongoDB, improve CI/CD and test automation, lead L3 support, and use AI tooling to accelerate the SDLC.

Design, develop, test, deploy, and support scalable cloud-native applications using Java, Spring Boot, React, TypeScript, Node.js, PostgreSQL, and microservices. Build REST APIs, integrations, CI/CD pipelines, containerized deployments, and observable production systems. Collaborate with Product, UX, QA, DevOps, Architecture, and engineering teams while troubleshooting issues and improving application performance, resilience, and maintainability.

Design and build scalable media platform systems for uploading, processing, managing, and serving image, video, and audio assets. Own complex backend projects, develop reliable distributed systems and REST APIs, integrate cloud services and GenAI technologies, collaborate across engineering teams, mentor teammates, and participate in production on-call rotations.

Design, develop, test, document, and maintain high-performance Java trading and brokerage systems. Build backend services integrating REST, WebSockets, and FIX; troubleshoot complex issues; provide escalated support; collaborate across product and engineering teams; and deliver reliable, low-latency features within a mature codebase.

Design and implement high-performance Java platform components that improve reliability, efficiency, and productivity across Uber’s backend services. Lead architecture, optimize JVM and distributed-system performance, support modern Java adoption, develop scalable platform designs, and collaborate with platform teams on technical improvements and developer tooling.

Develop and maintain Java-based applications, integrations, workflows, and services supporting an Oracle Identity Manager IAM platform. Responsibilities include troubleshooting production issues, performing root cause analysis, developing SOAP and REST integrations, configuring connectors, supporting Oracle SOA workflows, assisting with upgrades and modernization, and maintaining security and change-management documentation. The role collaborates with government stakeholders and requires the ability to obtain an IT-II security clearance.

Develop and maintain enterprise Java web applications using Spring Boot, REST, SOAP, SQL, and Flyway. Lead secure software development across the SDLC, including CI/CD automation, testing, vulnerability scanning, production support, troubleshooting, and root-cause analysis. Collaborate on integrations, modernization, Agile delivery, technical documentation, and application architecture. Evaluate and implement AI-enabled capabilities while maintaining security and regulatory compliance. The role is remote and requires eligibility for Public Trust screening.

Build and maintain enterprise workforce management software for forecasting, scheduling, adherence, intraday management, and reporting. Develop Java and Spring Boot microservices, React and TypeScript applications, REST APIs, event-driven workflows, integrations, and PostgreSQL data models. Support cloud-native deployments, CI/CD, testing, performance optimization, production troubleshooting, architecture discussions, and client-facing collaboration.

Build enterprise-scale workforce management software covering forecasting, capacity planning, scheduling, adherence, intraday management, and operational reporting. Develop Java and Spring Boot microservices, React and TypeScript applications, REST APIs, event-driven workflows, integrations, and PostgreSQL data models. Contribute to cloud-native deployments, CI/CD, testing, performance optimization, architecture, production support, and client-facing technical collaboration.

Build and operate cloud-native, AI-enabled applications for a financial services client. Develop React and TypeScript/JavaScript front ends with Java and Spring Boot microservices, deploy scalable AWS-based systems, integrate LLMs, RAG, MCP, and agent frameworks, maintain CI/CD pipelines, conduct automated and performance testing, and implement observability, security, and reliability practices. Collaborate with cross-functional stakeholders and troubleshoot production issues while working fully onsite.