Decentralized Gradle Build Cache Plugin

Plugin to use a decentralized network as a medium to fetch and share cache for Gradle builds.

Motivation:

Gradle build cache is a great feature to speed up builds by reusing outputs from previous builds. Reading the documentation i could find 2 ways of approaching this:

1. You could run your own build cache server, using the docker image for example
2. Using a managed service which probably is not free

There are plugins that you could use to store your build cache in a cloud storage:

• androidx/gcp-gradle-build-cache (using aws or gcp storage provider)
• craigatk/object-store-cache-plugin (reference to the project that i forked from)
• ... probably many more ...

The way i see it, running your own build cache server is not ideal, you would need to setup the server, configure and maintain it. I think a cloud storage solution is enough, it will probably be cheaper and easier to maintain, but you would still need to configure it, and worry about data transfer, but overall it sounds good.

This project tries to approach the problem from a different angle, instead of relying on a centralized server or cloud storage, the main goal here is to share cache between developers in a decentralized way, using a established peer-to-peer network. I couldn't find any other plugin that does this, so i decided to create one.

How it works:

Every time a developer compile the project, the plugin checks if someone on the network already has this build cache, if so, it downloads it and uses it. When you download the build cache, you also become a seed for it, so you can share with other developers.

If no one can provide the cache you need, your project compiles as it normally would, and after that the plugin announces to the network that you have this specific build cache available in case someone else needs it.

The decentralized network i chose is called IPFS, i highly recommend reading the documentation to understand how it works. For this project specifically, it satisfies the requirements and it seems to have support from the community, which is enough for me.

Usage

// TODO

Apply plugin in settings.gradle

// TODO

Configure build cache

// TODO

Compatibility

The plugin is compatible with Gradle 8.4 and higher and Java 21 and higher.