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41. Ad Click Aggregator: Low-Level Design
The classes and code behind the ad click aggregator: signed click tokens, a redirect that never waits on the log, and a stream counter that de-duplicates and handles late clicks. Tests run all of it.
Data engineeringMedium
Sharding Streaming Distributed systems
+6
HMAC Hot keys Idempotency Low-level design TypeScript Watermarks
Worked design
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