Galileo Asset File Format

Galileo is an asset file format for game engines, designed to be easy to implement, efficient to load, and simple enough to adapt to existing application designs.

The Galileo format can be implemented incrementally, only supporting a subset of asset types. For example if your application only needs mesh assets, you can choose to implement only Galileo Mesh assets without worrying about any of the other asset types.

The Galileo specification is a draft in early in development and is subject to change. This notice will be removed when the specification is released.




Metadata that is common to all asset types, and may be useful to know before parsing the entire file contents.

Primitive assets

Lowest level, “raw data” assets.

Aggregate assets

Assets that are collections of, or store references to other assets.


Provides application-specific data related to an asset.

Last modified May 1, 2024: Fix link to playdate (df85dd8)