Automerge

Automerge is a library which provides fast implementations of several different CRDTs, a compact compression format for these CRDTs, and a sync protocol for efficiently transmitting those changes over the network. The objective of the project is to support local-first applications in the same way that relational databases support server applications - by providing mechanisms for persistence which allow application developers to avoid thinking about hard distributed computing problems. Automerge aims to be PostgreSQL for your local-first app.

If you're looking for documentation on the JavaScript implementation take a look at https://automerge.org/docs/hello/. There are other implementations in both Rust and C, but they are earlier and don't have documentation yet. You can find them in rust/automerge and rust/automerge-c if you are comfortable reading the code and tests to figure out how to use them.

If you're familiar with CRDTs and interested in the design of Automerge in particular take a look at https://automerge.org/docs/how-it-works/backend/

Finally, if you want to talk to us about this project please join the Slack

Status

This project is formed of a core Rust implementation which is exposed via FFI in javascript+WASM, C, and soon other languages. Alex (@alexjg]) is working full time on maintaining automerge, other members of Ink and Switch are also contributing time and there are several other maintainers. The focus is currently on shipping the new JS package. We expect to be iterating the API and adding new features over the next six months so there will likely be several major version bumps in all packages in that time.

In general we try and respect semver.

JavaScript

An alpha release of the javascript package is currently available as @automerge/automerge@2.0.0-alpha.n where n is an integer. We are gathering feedback on the API and looking to release a 2.0.0 in the next few weeks.

Rust

The rust codebase is currently oriented around producing a performant backend for the Javascript wrapper and as such the API for Rust code is low level and not well documented. We will be returning to this over the next few months but for now you will need to be comfortable reading the tests and asking questions to figure out how to use it.

Repository Organisation

• ./rust - the rust rust implementation and also the Rust components of platform specific wrappers (e.g. automerge-wasm for the WASM API or automerge-c for the C FFI bindings)
• ./javascript - The javascript library which uses automerge-wasm internally but presents a more idiomatic javascript interface
• ./scripts - scripts which are useful to maintenance of the repository. This includes the scripts which are run in CI.
• ./img - static assets for use in .md files

Building

To build this codebase you will need:

• rust
• wasm-bindgen-cli
• wasm-opt
• node
• yarn
• cmake

The various subprojects (the rust code, the wrapper projects) have their own build instructions, but to run the tests that will be run in CI you can run ./scripts/ci/run.

Contributing

Please try and split your changes up into relatively independent commits which change one subsystem at a time and add good commit messages which describe what the change is and why you're making it (err on the side of longer commit messages). git blame should give future maintainers a good idea of why something is the way it is.