Simplicity just got a fresh new look. The redesigned site matches where the language is today: live on Liquid mainnet, running real financial contracts, and built for the developers and institutions creating the next generation of Bitcoin applications.
The refresh lands on the back of real progress. Post-quantum signatures are live on Liquid mainnet, the Lending v1 contract code is finalized, and teams across the ecosystem are already writing financial logic in Simplicity. The new site is built to show that off and to give every kind of visitor a place to start.
Proof Before Deployment
The idea behind Simplicity is one most Bitcoin developers will recognize as overdue. Countless smart contract failures of the past decade traces back to the same gap: code that nobody could prove was safe before it shipped. Reentrancy bugs, logic errors, runaway gas costs, and exploits that drained a contract in a single transaction all grew out of that one weakness.
Simplicity closes that gap. It's a low-level language expressive enough for advanced covenants and financial instruments, and formally verifiable enough to prove exactly how a contract behaves before it goes live. Because resource costs are calculated ahead of execution, there are no surprise fees and no out-of-gas failures mid-transaction. Developers write SimplicityHL, a Rust-like high-level language, and full nodes execute the compiled Simplicity underneath. A developer can open the IDE and deploy a first contract in a single click, then read the proof that it does exactly what it claims.
That combination of expressiveness and provability is what sets Simplicity apart from general-purpose smart contract platforms. It's purpose-built for finance, where a single unprovable assumption can cost a fortune.
Built for Capital Markets
The new site speaks directly to financial institutions through a dedicated Capital Markets page. The headline? High-assurance financial programming on Bitcoin. Simplicity enables contracts that are auditable and provable before deployment, predictable in cost, and settled on Liquid.
For institutions, that combination is the difference between hoping a system holds and knowing it will.
A Simplicity contract can be checked against its specification mathematically, so the security guarantees a financial application depends on are part of the language itself rather than bolted on afterward. Teams can build programmable capital markets, issue assets, and settle trades on Liquid, then reach out directly to put a contract into production.
A Growing Catalog of What's Possible
The new Apps page collects what's already being built on Simplicity: lending, automated savings, asset tokenization with enforced royalties, Bitcoin inheritance, peer-to-peer trading, post-quantum wallets, and two-party escrow.
It also works as a head start for new builders. Instead of opening an empty file, a developer can adapt a contract from the existing library, which shortens the path from an idea to a deployed application running on a real network.
Take a Look
We’re excited to kick off the next era of Simplicity. Explore the new site at simplicity-lang.org!
- Deploy a contract in the SimplicityHL IDE.
- Schedule a call to evaluate Simplicity for a financial application.
- Read the docs to go deeper on the language.