BooN Transfer 1.0: a native file transfer client for Linux

Anyone who runs servers moves files around all the time: plugins to the Minecraft server, backups to S3 storage, configs to a VPS. On Linux there was no tool I was really happy with. So I built one: BooN Transfer – the local file system on the left, the server on the right, and a queue in between that handles even large transfers reliably.

One program for every server

• SFTP and SCP for classic Linux servers, with password, key or SSH agent
• FTP and FTPS for web hosts and older systems
• WebDAV, for Nextcloud for example
• S3 and S3-compatible storage such as MinIO or Backblaze

Sessions are saved, passwords go into the system keyring and never end up on disk in plain text. Unknown or changed host keys have to be confirmed explicitly.

Transfers you don't have to restart

All transfers run through one shared queue: pause, resume, cancel, retry. If a connection drops, BooN Transfer continues where it left off instead of starting from zero. With SFTP, many requests are in flight at once – this compensates for long round trips and makes transfers over the internet much faster. Optionally, a SHA-256 checksum verifies that the file arrived unchanged.

More than copying

• Synchronise directories, with a preview of what will be transferred
• Built-in SSH terminal in its own window
• Edit files directly on the server
• Tabs, detachable windows, light and dark mode, German and English

Under the hood

The interface is written in React and TypeScript, everything beneath it in Rust. Tauri combines the two into a lean native application that uses the system WebView instead of shipping a whole browser. The interface itself has no direct access to files or the network – every action goes through a well-defined interface in the Rust core. SSH is implemented in pure Rust, TLS via rustls: no libssh2, no OpenSSL.

Version 1.0.1

After a full review of the code, 1.0.1 fixes a number of bugs. The most important one: changing file permissions via SFTP could empty the file. In addition, interrupted uploads now resume cleanly, large S3 uploads are sent in parts without loading the whole file into memory first, and modification times are preserved during transfers. All protocols were tested against real test servers for this release.

Installation

BooN Transfer is available as .deb, .rpm and AppImage on GitHub. The AppImage version updates itself; every update is signed and verified before it is installed.