> For the complete documentation index, see [llms.txt](https://docs.bvm.network/bvm/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.bvm.network/bvm/l3-scaling-solutions/what-are-bitcoin-appchains.md).

# What are Bitcoin appchains?

Bitcoin appchains (or Bitcoin L3s) are designed for application-specific blockchains.

They are ZK rollups. But instead of rolling up to Bitcoin directly, they roll up to a Bitcoin L2.

It is more cost-effective for smaller teams and indie developers to have their own blockchain and focus on a single application.

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