Bcachefs initiates a transition to Rust-based drivers
The upcoming v1.38.7 release will integrate Rust code directly into the kernel module, a move that complicates deployment while promising improved safety.
Adrian Volk
Jul 3, 2026 · 1 min read
The Bcachefs file system is moving past the user-space boundary. Starting with release 1.38.7, the project will begin incorporating Rust code within its core kernel driver. While initially introduced as a soft dependency, this shift marks a significant departure from C-only kernel development. Lead developer Kent Overstreet has acknowledged that this move creates logistical friction, particularly for users relying on the Dynamic Kernel Module System (DKMS), as Rust lacks a stable ABI and requires precise synchronization between the compiler and the kernel version.
To manage this complexity, Bcachefs is pivoting toward the distribution of binary packages. The transition highlights the broader tension within the Linux kernel community: the undeniable safety benefits of memory-safe languages versus the significant burden they place on existing build infrastructure. For Bcachefs, the decision is a bet on the long-term maintainability of the file system's logic over the immediate convenience of the build process.