Senior Software Engineer - API & MCP Platform

As a Senior Software Engineer on the API & MCP Platform team, you’ll be at the forefront of building and scaling ZoomInfo’s API infrastructure that handles millions of API calls weekly and powers integrations across our platform. You’ll work with Java and NestJS to develop robust, secure, and high-performance API services that enable seamless connectivity for our customers and partners.

You’ll design and implement scalable API architectures, establish best practices for API security and authentication, and build infrastructure that enables partners and customers to leverage ZoomInfo’s data at scale. Your expertise in API design, OAuth 2.0, and emerging technologies like Model Context Protocol (MCP) will be essential in creating world-class developer experiences.

Our engineering culture values diversity, intellectual curiosity, problem-solving, and openness. We encourage collaboration, big thinking, and calculated risk-taking in a blame-free environment. You’ll have the autonomy to work on meaningful projects while receiving the support and mentorship needed to grow your career., * Design, develop, and maintain scalable RESTful APIs using Java and NestJS framework

• Build APIs that power company and contact data enrichment, search, and intelligence capabilities
• Architect and implement secure authentication and authorization systems using OAuth 2.0
• Build high-performance API gateways with advanced rate limiting, throttling, and quota management
• Design and implement MCP (Model Context Protocol) tools and servers to enable AI-powered integrations
• Establish and enforce API design standards, versioning strategies, and best practices across the organization
• Optimize API performance, caching strategies, and response times for high-volume traffic (millions of calls daily)
• Design and implement comprehensive API documentation, SDKs, and developer tools
• Create MCP tool schemas, implement prompt best practices, and optimize tool discovery patterns
• Collaborate with product and integration teams to define API contracts and service-level agreements (SLAs)
• Implement monitoring, logging, and analytics for API usage patterns and performance metrics
• Participate in code reviews and mentor team members on API and MCP best practices
• Troubleshoot and resolve production issues in distributed API systems
• Contribute to technical architecture decisions for API platform evolution

Do you have a Bachelor’s degree?, * Bachelor’s degree in Computer Science, a related field, or equivalent practical experience

• 5+ years of experience in software development with strong focus on API development
• 3+ years of experience designing and implementing RESTful APIs and microservices at scale
• Strong expertise in Java frameworks (Spring Boot, Spring Security, Maven/Gradle)
• Strong expertise in NestJS framework
• Deep understanding of OAuth 2.0, OpenID Connect, JWT, and API security best practices
• Experience with API gateway technologies
• Proficiency with API design patterns, versioning, and documentation (OpenAPI/Swagger)
• Strong knowledge of rate limiting, throttling, and API scalability strategies
• Understanding of distributed systems and high-availability architectures
• Experience with MCP (Model Context Protocol) tool creation and implementation, * Experience releasing production MCP tools and servers
• Deep knowledge of MCP best practices, prompt engineering, and tool design patterns
• Familiarity with AI/LLM integration patterns and context management
• Experience with cloud platforms (AWS, GCP, or Azure)
• Knowledge of containerization and orchestration (Docker, Kubernetes)
• Experience with CI/CD pipelines and automated API testing
• Familiarity with message queuing systems (Kafka, RabbitMQ)
• Experience building developer portals and API documentation platforms
• Background in platform engineering or developer experience (DX) initiatives
• Active contributions to open-source API projects or MCP tool repositories

3.43.4 out of 5 stars Waltham, MA $140,000 - $200,000 a year

We want our employees and their families to thrive. In addition to comprehensive benefits we offer holistic mind, body and lifestyle programs designed for overall well-being. Learn more about ZoomInfo benefits here.