A Versatile OCaml Library for Git Operations

Vcs is an OCaml library for interacting with Git repositories. It provides a type-safe and direct-style API to programmatically perform Git operations - ranging from creating commits and branches, to loading and navigating commit trees in memory, computing diffs between revisions, and more.

Designed as an interface composed of traits, Vcs dynamically dispatches its implementation at runtime. It is currently distributed with two distinct backends: a non-blocking version built atop Eio, and a blocking variant based on OCaml's standard library. Both backends operate by executing git as an external process.

Documentation

Vcs's documentation is published here.

Examples

Explore the example directory to get a firsthand look at how Vcs works in practice.

Motivation

Our goal is to create a versatile and highly compatible library that can cater to a wide range of use cases, while also fostering community engagement. We also hope to gain practical experience with the use of provider-based parametric libraries.

Acknowledgements

We extend our gratitude to the following individuals and teams, whose contributions have been great sources of inspiration for the Vcs project:

The Eio developers for their work on the Eio project. The development of Eio has sparked a great deal of enthusiasm for us in our work on the Vcs project. We've also referred to Eio's Exn module in the design of Vcs's error handling.
The Jane Street developers for their significant contributions to the open source community. In particular, this project has drawn inspiration from the Mercurial backend of Iron, Jane Street's code review tool. For more details about how Iron has influenced this project and the licensing implications, please refer to the NOTICE.md file.
Vincent Simonet and contributors for headache, which we use to manage the copyright headers at the beginning of our files.
The Rresult developers: Their usage design guidelines have been a reference in the design of Vcs's error handling, the Vcs.Result module in particular.

We look forward to continuing to learn from and collaborate with the broader open source community.

Build

This repository depends on unreleased packages found in a custom opam-repository. You'll need to add this to your opam switch when building the project.

For example, if you use a local opam switch, this would look like this:

git clone https://github.com/mbarbin/vcs.git
cd vcs
opam switch create . 5.2.0 --no-install
eval $(opam env)
opam repo add mbarbin https://github.com/mbarbin/opam-repository.git
opam install . --deps-only --with-test --with-doc

Once this is setup, you can build with dune:

dune build @all @runtest

Current Status

We're currently seeking feedback as we write and publish the code and its dependencies to the opam repository. Please do not hesitate to open issues on GitHub with general feedback, requests, or simply start a discussion.