Blockstream Launches Simplicity: Bringing Enhanced Smart Contracts to Bitcoin

Bitcoin infrastructure developer Blockstream launched Simplicity, a specialized programming language designed to enable secure smart contracts on the Liquid Network, aiming to fill a functional gap in Bitcoin.

Simplicity, according to Blockstream Head of Research Andrew Poelstra, inherits Bitcoin’s commitment to security while borrowing aspects from the functionality offered by platforms like Ethereum.

Simplicity is tailored to run on Blockstream’s federated sidechain, Liquid. It is purpose-built with formal verification in mind, deliberately banning features like recursion, loops, and global state that can lead to errors and hacks.

This focus on safety and predictability allows developers to “mathematically prove” contract behavior before deployment, courted by the promise of attracting institutional investors wary of the risks associated with DeFi.

Funding solutions like SegWit2x and Samourai, Blockstream champions a modern Bitcoin stack and views Liquid as the route to introducing advanced capabilities, including smart contracts, onto the Bitcoin blockchain.

According to Bitcoin Runes developer Bob Bodily, the primary Bitcoin scripting language (“Bitcoin Script”) lacks the complexity needed for full smart contracts, being limited and “not Turing-complete.”

Simplicity explicitly targets the vulnerabilities of languages like Solidity (“paving the cowpaths”). By prohibiting recursion and loops, the language aims for efficiency and resource predictability.

Unlike direct Bitcoin Layer-1 smart contracts, Simplicity operates on the Liquid Network, a federated environment managed by the Liquid Federation. While offering faster, more private execution, this creates concerns regarding decentralization and censorship.

The long-term aspiration is for Simplicity to facilitate secure programmable applications (“DeFi++”) directly on Bitcoin’s base layer, offering institutional-grade finance without compromising Bitcoin’s core principles, potentially solidifying its position as a secure store-of-value and settlement layer.