Bitcoin development firm Blockstream has unveiled "Simplicity," a programming language for smart contracts built on the layer-2 network Liquid. Co-founded by cryptographer and early Bitcoin contributor Dr. Adam Back, Blockstream has introduced Simplicity with the aim of solving the limitations of Bitcoin as a venue for smart contracts. "Simplicity gives Bitcoin expressive smart contracting power, but without the security problems associated with VM-based chains," said Back in an emailed announcement on Thursday. "It’s built from the ground up to be formally specified, secure, and efficient.” The push for Bitcoin-native programmability has gained momentum in recent years, especially since the introduction of BitVM in 2023 , a framework that explored how complex computations could be verified on Bitcoin without altering the base protocol. Simplicity's origins in fact predate BitVM, having been conceptualized by Blockstream research Dr. Russell O'Connor in 2012. It is designed to enable smart contracts eschewing some of the features like unbounded loops that can lead to vulnerabilities and exploits on networks like Ethereum. Instead, Simplicity uses Bitcoin's UTXO model, whereby tokens function like digital cash and users spend specific coins, as opposed to account balances being updated. Simplicity is now live on the Liquid Network, a Bitcoin layer-2 with over $3 billion in total value locked (TVL), allowing developers to build many of the applications commonplace on smart contract-enabled blockchains, such as programmable vaults, decentralized exchanges, custody services and governance protocols, using Bitcoin as the settlement layer.
