58. Design a Dating App like Tinder
Stacks of nearby people in under 300 ms, 2 billion swipes a day, and a match never missed even when both like at once.
ClassicMedium
Guided practice
Start with a template. Work through each step. Ask Coach when you need a second opinion.
Designs with worked examples 3
Ordered by design numberCompany tags are community-reported. Counts on cards show how many people reported that design.
Bloom filterClear filters
82. Design Counting at Scale with Probabilistic Data Structures
Unique visitors, top pages, seen URLs and p99 latency over 10 B events a day with HyperLogLog, Count-Min, Bloom filters and t-digests.
ClassicMedium86. Design an IP and URL Denylist
Deny requests by caller address, range or URL at a global edge, with lists from governments, threat feeds and detection reaching 300 proxies in seconds.
ClassicMedium