Flux

Flux is a GTK4/Libadwaita file manager for Linux, written in Rust. It opens instantly, looks at home on GNOME and Wayland, and can be driven from the keyboard.

The icons shown in the screenshot are from WhiteSur Icon Theme (GPL-3.0).

Startup time

Cold start on a Ryzen 5 5600X, mean of 10 runs:

File manager	Startup
Flux	105 ms
PCManFM	134 ms
SpaceFM	169 ms
Thunar	290 ms
Nautilus	743 ms

Features

• Archives behave like folders. Open zip, 7z, rar, tar, iso and deb files like any directory, without extracting.
• Built-in search. Type to filter the folder, press Ctrl+F for a search panel, or start with : to search inside files. No index, no background service.
• Servers and drives. SMB, SFTP, FTP, WebDAV, NFS, MTP and Google Drive, plus encrypted LUKS volumes.
• Integrated terminal. Press F4, cd somewhere, and the file view follows.
• Tags. Label files and find them with #tag or Ctrl+Shift+T. Tags use the standard user.xdg.tags attribute, so they stay with the file.
• Preview panel. Images, video, audio, PDFs, code, Markdown, CSV, Office documents and fonts.
• Custom icons and covers. Set icons per file type, file or folder, including in bulk from the command line.
• Show/hide from a keybind. flux-fm --toggle, --show and --hide control the running window, so one compositor shortcut is enough. --toggle and --show start Flux if it isn't running.

Press F1 inside Flux for the full list of shortcuts.

Grid mode vs list mode

Flux switches to list mode automatically for folders with more items than the Auto List Mode Threshold (default 300), which keeps it responsive with several thousand items. Change it in Settings → Behavior, or set it to 0 to always use the mode chosen in the header.

Install

Flux needs GTK 4 and libadwaita 1.5 or newer, so Debian 12 and Ubuntu 22.04 are too old.

Pre-built AppImage (any distro)

For a quick test without installing anything:

Download the latest from the Releases page. The AppImage bundles GTK 4 and libadwaita, so it runs on any modern x86_64 Linux.

chmod +x Flux-x86_64.AppImage
./Flux-x86_64.AppImage

Flatpak (FlatPark)

flatpak remote-add --if-not-exists flatpark https://dl.flatpark.org/flatpark.flatpakrepo
flatpak install flatpark io.github.killown.flux

Arch (AUR)

yay -S flux-filemanager-git

From source

Install the dependencies first.

Debian / Ubuntu:

sudo apt install build-essential cargo fish pkg-config git gettext desktop-file-utils libadwaita-1-dev libgtk-4-dev libpango1.0-dev libgraphene-1.0-dev \
  libcairo2-dev libgdk-pixbuf-2.0-dev libpoppler-glib-dev ffmpeg imagemagick icoutils p7zip-full

Fedora:

sudo dnf install gcc make cargo fish pkgconf-pkg-config git gettext desktop-file-utils libadwaita-devel gtk4-devel pango-devel graphene-devel cairo-devel \
  gdk-pixbuf2-devel poppler-glib-devel ffmpeg ImageMagick icoutils p7zip

Arch:

sudo pacman -S base-devel rust fish git gettext desktop-file-utils libadwaita gtk4 glib2 pango graphene cairo gdk-pixbuf2 poppler-glib \
  ffmpeg imagemagick icoutils ttf-nerd-fonts-symbols p7zip

If your distro's Rust is too old to build Flux, install a current toolchain with rustup instead.

Then build and install:

git clone https://github.com/killown/flux.git
cd flux
cargo build --release
make install

make install installs for the current user into ~/.local (make sure ~/.local/bin is in your PATH), copies the default menus and helper scripts, and downloads community themes (needs git and a connection; skipped offline).

Optional extras:

• Network browsing: gvfs plus a backend such as gvfs-smb or gvfs-sftp.
• LUKS: cryptsetup and udisks2.
• Menu editor icons: the Nerd Font symbols font in ~/.local/share/fonts, then fc-cache -f (Arch gets it from the package above).
• Default right-click menu: some entries call tools such as alacritty, wl-clipboard, yt-dlp or Python with PyGObject. Edit menu.rs to match what you have installed.

If you see occasional slow startups, try a lighter icon theme such as Adwaita or refresh your theme's icon cache with sudo gtk-update-icon-cache -f /usr/share/icons/<theme>.

Customization

• Settings live in ~/.config/flux/config.toml, and most are available in Preferences (F10).
• Style the interface with CSS in ~/.config/flux/style.css: every selector Flux uses is listed with a comment, empty, fill in what you want to change. It reloads when you save. For a full replacement look, drop a theme in ~/.local/share/flux/themes/<name>/theme.css. See Theme customization.
• Themes go in ~/.local/share/flux/themes. Community themes are in flux-themes.
• Right-click menus are defined in ~/.config/flux/menu.rs, or edit them with the built-in editor (F9). Ctrl+Right-Click opens a second, file-type-specific menu.
• Set or reset icons in bulk, one TARGET<TAB>IMAGE pair per line:

printf '%s\t%s\n' ~/Videos ~/icons/video.svg ~/Music ~/icons/music.svg | flux-fm --set-icons-stdin

Under the hood

Rust, Relm4 and GTK4, Tokio and Rayon, Nucleo for fuzzy matching, the ignore crate for directory walking, and SQLite for tags. 600+ tests (sh tests.sh), and the parsers are fuzzed with libFuzzer.

Contributing

Pull requests are welcome. For big changes, open an issue first, and please run the tests before sending.

License

GPLv3