Kupfer

Free plan Linux

What Kupfer is

Kupfer is a free, keyboard-focused Linux interface for quickly opening applications, documents, files, and commands. Users can configure accelerator keys for frequent actions, while plugins extend access beyond applications and support workflows. Documented plugins include Applications, Calculator, Favorites, Notes, Thunar, and Triggers. The project is licensed under GNU General Public License v3 or later. Its homepage identifies version v321 and provides a source tarball; packages are also available in Ubuntu and Debian repositories and Arch Linux’s community repository. Runtime requirements include Python 3.9 or later, GTK 3.22, libkeybinder 0.3.1, Python GObject introspection, D-Bus Python bindings, and python-xdg. Normal use needs an active D-Bus session bus, and only one Kupfer instance can run per user. Wnck 3.20 is recommended for focusing already running applications. Users can substitute a window-manager keybinding for Keybinder. Guides, technical documentation, and an IRC discussion channel are linked.

Who it suits

Kupfer suits Linux users who prefer keyboard-driven launching and searchable access to applications and documents. Plugin support makes it useful for users wanting calculators, notes, file tools, or custom workflows.

What it does well

Free and GPLv3-or-later licensed
Keyboard accelerator keys are configurable
Plugins extend accessible objects
Available through major Linux repositories
Supports command launching and workflows

What to know first

Linux only
Requires several runtime dependencies
Needs an active D-Bus session bus
Only one instance per user

Verdict

Kupfer offers keyboard-first launching with plugin-based extensions for Linux desktops. Its dependency and D-Bus requirements matter when setting it up, especially on systems without the listed components.

Facts from Kupfer's own pages

Distribution: The project says Kupfer is available through Ubuntu and Debian repositories and Arch Linux’s community repository. · kupferlauncher.github.io, 4 Oct 2026
Documentation: The user guide is available as Mallard help pages in the application and on the project website, and it is translatable. · github.com, 4 Oct 2026
Extendable: Plugins extend Kupfer’s quick access to objects beyond applications. · kupferlauncher.github.io, 4 Oct 2026
Intended users: The maker describes using Kupfer to find and launch applications and quickly access their documents. · kupferlauncher.github.io, 4 Oct 2026
Keyboard shortcut dependency: Kupfer can run without Keybinder if the user assigns a window-manager keybinding to the kupfer binary. · github.com, 4 Oct 2026
Keyboard use: Kupfer is keyboard-focused and lets users configure accelerator keys for frequently used actions. · kupferlauncher.github.io, 4 Oct 2026
Latest version: The homepage identifies v321 as the latest version and links to a source tarball. · kupferlauncher.github.io, 4 Oct 2026
License: The project is licensed under GNU General Public License v3 or any later version. · github.com, 4 Oct 2026
Linux availability: The maker says Kupfer is available in Ubuntu and Debian repositories and in Arch Linux’s community repository. · kupferlauncher.github.io, 4 Oct 2026
Plugin dependencies: Some plugins require additional Python modules. · github.com, 4 Oct 2026
Plugin development: Kupfer loads Python extension modules at runtime, with plugins implemented as Python files or packages. · kupferlauncher.github.io, 4 Oct 2026
Plugin examples: The manual documents Applications, Calculator, Favorites, Notes, Thunar, and Triggers plugins. · kupferlauncher.github.io, 4 Oct 2026
Plugins: Plugins extend Kupfer’s quick access to objects beyond applications. · kupferlauncher.github.io, 4 Oct 2026
Purpose: Kupfer is an interface for quick access to applications and their documents. · kupferlauncher.github.io, 4 Oct 2026
Running applications: The README says Wnck 3.20 is recommended; without it, Kupfer cannot focus already running applications. · github.com, 4 Oct 2026
Runtime limit: Normal use requires an active D-Bus session bus, and only one Kupfer instance can be active per user at a time. · github.com, 4 Oct 2026
Runtime requirements: Kupfer requires Python 3.9 or later, GTK 3.22, libkeybinder 0.3.1, Python GObject introspection, D-Bus Python bindings, and python-xdg. · github.com, 4 Oct 2026
Session requirement: Normal use requires an active D-Bus session bus, and only one Kupfer instance can run per user at a time. · github.com, 4 Oct 2026
Source release: The site lists version v321 and a source tarball for download. · kupferlauncher.github.io, 4 Oct 2026
Support and documentation: The site links to a user guide and technical documentation, and lists an IRC channel for discussion. · kupferlauncher.github.io, 4 Oct 2026
System requirements: The repository lists Python 3.9 or later, GTK 3.22, libkeybinder 0.3.1, Python GObject introspection bindings, D-Bus Python bindings, and python-xdg as runtime requirements. · github.com, 4 Oct 2026