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System Design at Calendly
System Design at Calendly
Calendly powers more than a million daily meeting bookings across 20+ million users, where the hard parts are timezone math, third-party calendar sync, conflict detection, and computing availability under heavy concurrency. System design rounds emphasise the scheduling engine itself, availability data models, and how to keep external calendar state consistent.
1 guide available•Interview focus: Scheduling engines, availability computation, calendar sync, and conflict detection.
Calendly System Design Interview Guides
Nov 10, 2025•18 min•
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How to Design Google Calendar - Complete System Design Guide
Master Google Calendar system design for your next big tech interview. Learn database schema design, the right way to handle timezones, how recurring events act...
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