--- title: Introduction --- The Solana Program Library (SPL) is a collection of on-chain programs targeting the [Sealevel parallel runtime](https://medium.com/solana-labs/sealevel-parallel-processing-thousands-of-smart-contracts-d814b378192). These programs are tested against Solana's implementation of Sealevel, solana-runtime, and deployed to its mainnet. As others implement Sealevel, we will graciously accept patches to ensure the programs here are portable across all implementations.