An independent project has released an early Rust reimplementation of Mosh, the roaming remote-terminal software, with a native Windows client and optional terminal scrollback. The project, called mosh-rs, describes its current v0.1.2 release as pre-alpha and says it is not affiliated with MIT, Mosh creator Keith Winstein or the upstream maintainers.
Mosh is designed to keep terminal sessions usable across unreliable links, laptop sleep and changes between networks. Instead of streaming terminal bytes in the same manner as a conventional SSH session, it communicates over UDP, maintains synchronized screen state and predicts local keystrokes while awaiting the server. Mosh-rs says it ports the upstream project's protocol and terminal behavior into Rust while remaining wire-compatible with Mosh 1.4.0.
That compatibility is intended to let users install only the new client while continuing to connect to an existing Mosh server. The added scrollback mode is different: it requires a mosh-rs server at the remote end and must be enabled explicitly with a command-line option. Ordinary sessions retain the upstream behavior and do not record history. The server can cap undelivered scrollback data, with the project documenting a default limit of 32 MiB.
The Windows build supplies an x86-64 client and launcher that use the OpenSSH client included with modern Windows releases. The project says it also ran that build on Windows 11 for Arm through Microsoft's x64 emulation. There is no Windows server; users still need a Linux or macOS host running either upstream Mosh or the Rust implementation. Linux binaries are distributed as static builds, while macOS builds are also available.
The repository documents compatibility testing against upstream C++ components and scripted sessions under impaired network conditions. It also records an early macOS launcher fault in v0.1.0, caused by reading a socket address using a Linux-specific layout; v0.1.1 corrected that issue. The maintainers provide checksums with release archives and mark untested combinations in a limitations list.
Installation details reflect the project's experimental stage. The repository warns that the similarly named `mosh-rs` package on crates.io is unrelated; its own package is published as `mosh` and requires Rust 1.89 or newer when built through Cargo. Release archives retain the `mosh`, `mosh-client` and `mosh-server` program names so existing scripts can invoke the expected commands.
The security caveat is significant. Mosh-rs says it has not received an independent security audit, even though its cryptographic and transport code follows the upstream implementation closely. It therefore presents v0.1.2 as a preview for testing rather than a mature replacement. Users evaluating it gain a path to native Windows access and local terminal history, but should weigh those conveniences against the project's pre-alpha status and documented gaps.
