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Design BookMyShow / Ticketmaster (Concurrent Seat Booking)
HLDProblem Understanding
Restate the problem in your own words.
Design BookMyShow / Ticketmaster (Concurrent Seat Booking)
Design a BookMyShow / Ticketmaster ticket-booking system: users browse events + showtimes, select seats from an interactive seat-map, hold the seats for ~5 minutes while they pay, then commit on payment success. The hard parts are seat locking under concurrent demand (a sold seat must NEVER be sold twice), surge handling for blockbuster releases (10× normal QPS for the first 30 minutes), and the saga that ties booking to payment with idempotent retries.
- BookMyShow (India)~10M bookings/day at peak; the canonical ticketing surface in India.
- TicketmasterLive-event ticketing at hyperscale; famous for queue + bot-protection on stadium drops.
- EventbriteLong-tail event ticketing; smaller events but the same seat-lock + payment saga pattern.
- Cinemark / AMCCinema-chain booking with a dedicated seat-map per auditorium; the simplest seat-locking case.
Your task: read the problem above, then write what the system is, who uses it, the rough scale, and the headline UX expectation — in your own words. Submit for AI review when you're ready.
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