IBM Engineer Has Been Exploring Possible Rust Modules For GRUB
The proposal is not about rewriting GRUB2 in Rust or transitioning it in any large part to Rust, but allowing GRUB2 modules to be created in Rust if so desired by developers. Similar to the growing number of other projects adopting Rust, the motivation is on the prospects of safer code compared to C.
Given the widespread use of GRUB and being an important part of the Linux boot process and the growing security emphasis there from UEFI SecureBoot to measured boot to TrenchBoot and many other secure/trusted-booting efforts, it makes sense to use Rust in some areas.
Daniel's presentation did note that roughly 40% of recent GRUB CVE security vulnerabilities related to memory (un)safety issues.
There still are many open questions and design items as well as whether the GRUB2 development community at large wants to embrace Rust support for modules, but given the trend with other open-source projects, it wouldn't be a surprise to see this materialize.
See the presentation below and the slide deck.