itch uses a few external tools to download & manage content.
It installs and keeps them up-to-date automatically, which means you should never have to worry about them. However, in the interest of you knowing what runs on your computer, they're documented here.
Everything is downloaded from our download server at
Third-party programs are built from source. Home-grown programs are continuously built on our CI servers.
All dependencies are downloaded and extracted into the following folders:
~/Library/Application Support/itch/brothon OSX
butler is a homemade (itch.io-made) command-line tool, distributed under the MIT license.
Its source code is available here, for you to audit, debug, and improve at will:
Building your own version is as simple as running:
go get -v github.com/itchio/butler
(assuming you have Go 1.9+ installed on your system)
The logic for downloading, extracting and installing itch dependencies can be found in the
The authors are aware of the irony of having an ad-hoc, half-baked Implementation of a package manager inside a package managing application, itself installed by various other package managers, and there is no need to point it out!