> For the complete documentation index, see [llms.txt](https://docs.applayer.com/testnet/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.applayer.com/testnet/how-applayer-works/appchains.md).

# Application Chains

An application chain, also known as an AppLayer™, are blockchains built using AppLayer's Blockchain Development Kit (BDK) and are deployed on AppLayer's Chain Abstraction Layer. An AppLayer™ primarily enables developers to create a chain dedicated to a particular application, with the chain’s rules tailored to the security, performance, speed, decentralization and other service delivery needs of the application. These AppLayers are responsible for securing their own ledger of accounts and balances along with their own execution.

AppLayer's BDK currently supports C++ and Solidity for development with plans for other languages such as Rust, C#, Golang, and more. These application chains compile to a binary to enable efficient execution in parallel to Solidity byte code. Additionally, whoever sets up an application chain is in charge of validating the transactions on it and attracting others to run validators.


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