NexKey is a Vietnamese typing tool for Linux, inspired by UniKey, that works on both Fcitx5 and IBus.

Issue: Linux users often face underlined typing when inputting text, slow performance in some applications, or corruption of English words like "windows," "jazz." NexKey has been completely rewritten in version 2.0 to address these issues.

Main features:

• Direct typing, no underlining (non-preedit): text appears straight in VS Code, Chrome, terminal, LibreOffice, compatible with X11 and Wayland.
• Application-specific rules: for example, code uses Telex, gnome-terminal disables typing, firefox uses VNI.
• Shortcut typing macros include $TIME and $DATE, automatically restores non-Vietnamese text, emoji selection box with fuzzy search.
• Includes Telex, Simple Telex, VNI, VIQR, Microsoft input tables; supports Unicode, NFD, TCVN3, VIQR encoding, and converts old documents via CLI.
• Backup and restore entire configuration in JSON format.

Who should use it: Ubuntu, Debian, and other distributions users who need to type Vietnamese daily for programming, documentation, messaging, especially those familiar with UniKey.

Getting started: install via .deb package (Ubuntu 24.04), AppImage, or build from source using CMake. Then enable NexKey in fcitx5-configtool or ibus-setup. The default switch key is Ctrl+Shift.

Differences: C++23 engine with no external library dependency, a single configuration file for both backends and the Qt6 system tray application, open source under the MIT license.

supported by Hyggshi OS Foundation and Research Technology