butler

butler is a small command-line tool that lets you:

• Upload builds of your games quickly & reliably to itch.io
• Generate patches and apply them offline

When someone refers to the itch.io command-line tools, they're talking about butler.

Prefer not to use the command line? The itch app (v26.12.0 or later) includes a graphical interface for pushing builds with butler, with no terminal required. It handles uploads, change previews, and build management from a Builds page in the sidebar. Read the announcement for details:

• https://itch.io/updates/pushing-builds-with-butler-is-now-in-the-itch-app

butler is easily integrated into an automated build/deploy pipeline. Like most of the itch.io delivery infrastructure, it is open-source (MIT licensed):

• https://github.com/itchio/butler

It is also a good showcase of the Wharf open specification, using only openly documented algorithms and file formats, encouraging the development of compatible tools:

• https://itch.io/docs/wharf/

And is used by the itch app for various operations.

Keep reading to learn how to use it! First you'll want to install butler.