You are building the backend for an online chess site with 20 million players.
This is a dev post classified by AGK Intelligence as Backend & APIs (a tutorial), kept by the Dev Radar because it carries real work, not commentary.
Interviewer: You are building the backend for an online chess site with 20 million players. 100,000 players click "Find Match" at the exact same second. Every player needs to be paired with someone within ± 50 Elo rating points and under 80ms network ping, in less than 1 second, without two servers accidentally matching the same player twice. How do you architect the matchmaking queue?
Posted by Arika (9k followers) 2 h ago · 11 likes · 943 views · view the original post on X. Kept by the Dev Radar as Backend & APIs.
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