# Gemachain Program Use the Gemachain Program Crate to write on-chain programs in Rust. If writing client-side applications, use the [Gemachain SDK Crate](https://crates.io/crates/gemachain-sdk) instead. More information about Gemachain is available in the [Gemachain documentation](https://docs.gemachain.com/). [Helloworld](https://github.com/gemacoin/example-helloworld) and the [Gemachain Program Library](https://github.com/gemacoin/gemachain-program-library) provide examples of how to use this crate. Still have questions? Ask us on [Discord](https://discordapp.com/invite/pquxPsq)