Principal Software Engineer (Waltham)

ZoomInfo is where careers accelerate. We move fast, think boldly, and empower you to do the best work of your life. You’ll be surrounded by teammates who care deeply, challenge each other, and celebrate wins. With tools that amplify your impact and a culture that backs your ambition, you won’t just contribute. You’ll make things happen–fast.About the Role:We are seeking an experienced Principal Software Engineer to lead the design and development of ZoomInfo's customer-facing GraphQL API platform, built on top of our industry-leading Go-to-Market (GTM) data assets.You will be a technical anchor for a collaborative engineering team, setting architectural direction for how enterprise customers and partners programmatically access the world's most comprehensive B2B intelligence. This is a high-impact individual contributor leadership role where your decisions directly shape platform quality, scalability, and customer success.What You'll Do:- Architect, design, and own the end-to-end development of ZoomInfo's customer-facing GraphQL APIs, ensuring high availability, low latency, and developer-friendly experiences.- Define schema design standards, versioning, deprecation, and backward-compatible evolution across product surfaces.- Work with product managers and data engineers to expose ZoomInfo's GTM data assets (BigTable, BigQuery, Solr) through well-structured, queryable API surfaces.- Implement and enforce API security, OAuth 2.0, JWT, RBAC, rate limiting, and query complexity controls.- Maintain production reliability through CI/CD pipelines (Jenkins, ArgoCD) and observability practices using Datadog.- Use AI tooling (Claude, GitHub Copilot) as part of your daily workflow and help the team do the same responsibly.- Lead code and design reviews, mentor senior engineers, and contribute to the engineering roadmap.What you bring:- Deep GraphQL expertise: schema design, resolvers, federation, subscriptions, and performance optimization. Experience with GraphQL Yoga or Apollo Server (transferable skills).- Strong Node.js and TypeScript skills for API services and developer tooling; Go experience for backend and infrastructure work.- Experience securing customer-facing APIs, OAuth 2.0, JWT, fine-grained authorization, rate limiting.- Familiarity with large-scale data systems; exposure to BigTable, BigQuery, or Solr is a plus.- Experience building developer-facing SDKs or API tooling. You think about the API consumer, not just the implementation.- Familiarity with AI coding tools (Claude, GitHub Copilot); experience with AI Agents or MCP tooling is a bonus.- Clear communicator who can drive technical decisions and bring along both engineering and non-engineering stakeholders.Ideal Background:- 8+ years of software engineering experience, with a focus on production-grade, customer-facing APIs at scale.- Prior experience owning a developer-facing API platform at a SaaS or data company.- Bachelor's or advanced degree in Computer Science, Engineering, or a related field.#LI-SK1#LI-HybridActual compensation offered will be based on factors such as the candidate’s work location, qualifications, skills, experience and/or training. Your recruiter can share more information about the specific salary range for your desired work location during the hiring process. 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.Below is the US base salary for this position. Additional compensation such as Bonus, Commission, Equity and other benefits may also apply.$163,800—$257,400 USDAbout us:ZoomInfo (NASDAQ: GTM) is the Go-To-Market Intelligence Platform that empowers businesses to grow faster with AI-ready insights, trusted data, and advanced automation. Its solutions provide more than 35,000 companies worldwide with a complete view of their customers, making every seller their best seller.ZoomInfo is committed to protecting your privacy when you apply for jobs with us. Please review our Job Applicant Privacy Notice for more details on how we handle your personal information.ZoomInfo may use a software-based assessment as part of the recruitment process. More information about this tool, including the results of the most recent bias audit, is available here.ZoomInfo is proud to be an equal opportunity employer, hiring based on qualifications, merit, and business needs, and does not discriminate based on protected status. We welcome all applicants and are committed to providing equal employment opportunities regardless of sex, race, age, color, national origin, sexual orientation, gender identity, marital status, disability status, religion, protected military or veteran status, medical condition, or any other characteristic protected by applicable law. We also consider qualified candidates with criminal histories in accordance with legal requirements.For Massachusetts Applicants: It is unlawful in Massachusetts to require or administer a lie detector test as a condition of employment or continued employment. An employer who violates this law shall be subject to criminal penalties and civil liability. ZoomInfo does not administer lie detector tests to applicants in any location.