21st

118 posts

21st

@21st_dev

Building blocks for AI apps

San Francisco

Joined October 2025

Affiliates Replies Media

21st
@21st_dev
Jul 23
The best building blocks for video generation
Remocn
@_remocn
Jul 23
Say hello to my new sponsor. Thank you so much @sergeybunas and @21st_dev 🩵
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21st
@21st_dev
Apr 10
Introducing Agent Registry for Anthropic Managed Agents
serafim
@korablev
Apr 10
Introducing Agent Registry for Anthropic Managed Agents on @21st_dev Find the right config in seconds: → Semantic search - describe what you need, not keywords → Browse by MCP server - Slack, GitHub, Postgres, Sentry… → Filter by category - coding, devops, research, data,
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21st
@21st_dev
Mar 24
Let your agent set everything up for you
serafim
@korablev
Mar 24
Introducing the 21st SDK CLI. Deploy AI agents, manage env vars, and inspect logs — all from your terminal. Here’s how it works 🧵
21st
@21st_dev
Mar 7
We’re building Next.js for frontier agents!
sergey bunas
@sergeybunas
Mar 7
Article
21st Agents - Claude Code SDK is React. We’re building Next.js.
Hi, we're Sergey and Serafim from 21st.dev (YC W26). Motivation: 5 months ago we reverse-engineered Claude Code and re-implemented it on top of AI SDK. It felt powerful… for a moment…...
21st
@21st_dev
Mar 6
If you like UI components, you’re going to like our Agent Theme Builder
serafim
@korablev
Mar 6
Agents SDK by @21st_dev comes with beautiful theme presets and a full theme builder Add an AI agent to your app, fully styled to match your product, in minutes. Play with it here - 21st.dev/agents/theme-b…
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