Tricky licence is under-documented.

[vi]

MIT/Apache-2.0 license is available for spacejam's github sponsors.
Cargo.toml

Rio seems to have a tricky licence: GPLv3 with exceptions. But I think this fact is not documented properly.

Primary places for licence to be visible are crates.io page, Github page and docs.rs page.

• On the crates.io page you see "GPL-3.0". Longer text about exceptions only briefly blinks though until README is loaded.
• On Github, you don't see any licence info in README, but see LIZENZ file, which is for GPLv3 without mentioning the exception.
• On the docs.rs page there's nothing about licence at all.

I suggest to copy that phrase from the description inside Cargo.toml to README and to root module doccomment. Maybe a longer document about how the exception is granted, when it is terminated and other lawyery details can be provided in the repository.

Related: #3 #16

[rcxdude]

I think it's just GPLv3. There's no exceptions in the license, it's just the code is also available to some people under a different license. This is basically just a standard multi-license situation. As mentioned in those comments there's nothing in the license preventing someone who gets it from spacejam under a more permissive license from simply resharing it under that license (just 'bad karma').