microsoft/litebox

Litebox is a security-focused library operating system that supports both kernel-mode and user-mode execution.

The project addresses the need for a computing environment where security properties can be enforced at the OS level while maintaining flexibility in execution contexts. Litebox implements a library OS architecture, meaning applications link against it directly rather than relying on a traditional separate kernel. This approach allows the security model to be tightly integrated with application code, reducing the attack surface by eliminating certain classes of kernel-userspace boundary vulnerabilities. The dual support for kernel-mode and user-mode execution means developers can choose the execution context that best fits their security and performance requirements.

Litebox suits projects where security guarantees are a primary concern and where the overhead of traditional OS abstractions is acceptable. Teams building systems that need strong isolation properties, verified security properties, or protection against specific kernel-level attacks should evaluate it. The library OS model means applications must be explicitly built or adapted to use Litebox rather than running unmodified binaries, so it is most appropriate for new projects or those undergoing significant refactoring rather than as a drop-in replacement for existing systems.

The project is written in Rust, which provides memory safety guarantees that complement the security-focused design. Development activity shows consistent engagement with the codebase through regular commits and active maintenance of the core implementation. The project maintains documentation and examples that support understanding its architecture and integration patterns. Issue tracking and pull request activity indicate ongoing refinement of the library OS implementation and responsiveness to technical concerns raised by users.