Per the Rust FAQ [1]:
> The Apache license includes important protection against patent aggression, but it is not compatible with the GPL, version 2. To avoid problems using Rust with GPL2, it is alternately MIT licensed.
The Rust API guidelines also recommend the same: https://rust-lang.github.io/api-guidelines/necessities.html#...
[1]: https://github.com/dtolnay/rust-faq#why-a-dual-mitasl2-licen...
From my perspective (as the author of Graft) my goal was to be open source and as compatible as possible with the Rust ecosystem. Hence the choice to dual license.
Thank you! That is helpful, and understandable from that context. I to try to follow the best standards surrounding the language I use for a given project.