MUD v2 is still in alpha

Please note that MUD v2 is still under development and some APIs may change! Stay up to date with MUD core development, changes, and roadmap by checking out the Github repo and join the MUD Discord

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MUD is a framework for ambitious Ethereum applications. It compresses the complexity of building EVM apps with a tightly integrated software stack.

MUD comes with:

  1. Store: An onchain database. No more bespoke data modeling for each app and gas-golfing events.
  2. World: An entry-point kernel that brings standardized access-control, upgrades, and modules.
  3. Blazing fast development tools based on Foundry (opens in a new tab)
  4. Client-side data-stores that magically reflect onchain state. No need to use view functions and events to get your contract data.
  5. MODE: A Postgres database you can query with SQL that reflects your onchain state 1 to 1. Never write an indexer again.

The projects built with MUD speak for themselves: some of the most complex applications on Ethereum have been built with the framework in record time. OPCraft, a fully onchain voxel world, was built by Lattice in 1.5 months. While it didn’t have the security and auditing requirement of financial applications, it handled more transaction throughput than most apps on Mainnet ever did in their lifetime: in 10 days, OPCraft players made 3.5 million transactions, filling the MUD onchain database with billions of gas worth of storage; with the client seamlessly handling synchronizing that state back. OPCraft used MUD without any additional tricks: large onchain applications with minimal client headaches can be yours too!

MUD is maximally onchain: the entire application state lives in the EVM, and the only requirement for clients and frontends is an Ethereum Node or a MODE — a MUD node. You can use all MUD libraries together as a framework and get super-powers, or only pick the parts you like. It’s up to you!

Community support

Join our Discord (opens in a new tab) to get support and connect with the community!

Check out our community wiki (opens in a new tab) for MUD projects and MUD-related articles, videos, and podcasts.


MUD is open-source software licensed as MIT.