Updated April 29, 2026
21st.dev is the largest React component registry for the agentic internet — an open-source, community-driven marketplace of shadcn/ui-based React + Tailwind components, blocks, and hooks. 1.4M developers (200K MAU), pivoting into a full agent deployment SDK.
Llama Stack is Meta's standardized API and SDK for building AI applications on top of Llama models. It provides a unified interface for inference, safety, memory, and agentic workflows — with swappable providers for local, cloud, and on-device deployment. As the official framework for the Llama ecosystem, it is becoming the default for teams building on open-source Llama models.
Core capabilities each platform advertises.
What each tool does well, and the limitations to keep in mind.
Pros
Cons
Pros
Cons
Saves so much time — broad set of high-quality, free components, including 3D. Smooth React and Next.js integration.
Read full reviewChoose 21st.dev if you wantChoose if you want
Choose Llama Stack if you wantChoose if you want
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