Frontend Platform Engineer III

What’s in it for you?

Ready to make a serious impact? Millions of people already rely on Calendly, and we’re still in the midst of exciting product growth — it’s a fantastic time to join us. Everything you’ll work on here will accelerate your career to the next level. If you want to learn, grow, and do the best work of your life alongside the best people you’ve ever worked with, then we hope you’ll consider allowing Calendly to be a part of your professional journey.

About the team & opportunity

Our Mission

We power Calendly's products with reliable, high-performance calendar data infrastructure. Our services provide the foundation for how users interact with their scheduling data, serving as the single source of truth across our platform.

How you will contribute

As a Frontend Platform Engineer on Calendly’s App Platform team, you will be instrumental in building the foundational capabilities that power our product ecosystem. Your work will directly impact how our engineering teams ship features and the quality of experience they deliver to millions of Calendly users.

You will focus on critical platform services including:

• Shared frontend packages which are used in numerous frontend web applications
• Frontend architecture and shared application scaffolding used as the foundation for new products
• Real-time UX Infrastructure to enable server-to-client data delivery to support dynamic and responsive experiences
• Developer tooling and observability infrastructure to improve engineering velocity and frontend reliability.

Why this role matters

We're at an inflection point. As Calendly continues to scale, our product teams need increasingly sophisticated frontend platform capabilities to move quickly without sacrificing quality. In this role, you’ll help evolve our shared React architecture, package ecosystem, and developer experience. You’ll contribute to engineering standards, strengthen the reliability of our frontend infrastructure, and build the resilient tooling and migration paths our growing platform demands. Your technical collaboration will help shape not only what we build, but how we build across Calendly engineering.

A day in the life of a Frontend Platform Engineer at Calendly

Building Platform Infrastructure

Design, develop, and maintain the services and frameworks that product teams depend on. You will work hands-on with technologies like React and Webpack to build highly resilient, scalable systems; from real-time server-to-client data infrastructure to shared frontend services.

Contribute To Critical Initiatives

Contribute to significant projects from concept to production. Whether it’s building and launching real-time server-to-client infrastructure, optimizing package performance, or designing new platform capabilities, you will deliver high impact solutions with quality and reliability at the forefront.

Cross-Functional Partnership

Partner with product managers, designers, and engineering teams across Calendly to translate their needs into robust platform solutions that serve the entire organization. You will be a connector across teams, building relationships with product engineers and acting as a trusted liaison who advocates for platform solutions that make their work easier.

Operational Excellence

Ensure reliability and performance of platform services through thoughtful monitoring, testing, and incident response. Participate in on-call rotation to support business-critical systems and drive continuous improvement based on operational learnings.

What do we need from you?

• 3+ years