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21st: Production Layer for Frontier AI Agents

About: 21st (@21stdev) is the production layer for frontier AI agents. 1.4M developers already use their platform to build AI apps, 15K+ GitHub stars - now they're making it dead simple to deploy Claude C…
Product: 21st
Company: Y Combinator
Category: Developer tools
Posted: Mar 16, 2026
Duration: 0:55
Views on X: 33,716snapshot Sep 14, 2026
Author: @ycombinator
Original: View on X
Tags: 21st · launchgallery

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