vim-which-key is a Vim/Neovim plugin that provides an interactive keybinding guide. When a leader key is pressed, it intercepts subsequent keystrokes and displays available mappings in a popup or split window. The plugin dynamically parses native Vim mappings for the given prefix and merges them with user-defined description dictionaries to show meaningful labels and group names. It supports both Vim's popup API and Neovim's floating windows, offering a modern, non-intrusive UI. The architecture is modular: mapping parsing, layout rendering, window management, and key input handling are separated into distinct autoload modules. The code demonstrates solid Vimscript engineering, with careful handling of edge cases like timeout, exit codes, special keys, and fallback to native mappings.
tmux-which-key is a tmux plugin that provides a customizable popup menu for executing tmux commands and user-defined macros. The plugin architecture centers around a YAML configuration file that defines menu structure, keybindings, and macros, which is processed by a Python build script to generate tmux initialization code. At runtime, the plugin uses tmux's display-menu command to show nested menus and executes commands via command-aliases for performance. The plugin supports XDG directory compliance for immutable systems like NixOS and offers both YAML-based configuration (requiring Python) and direct tmux script editing alternatives. Key features include transient menus (that stay open for repeated commands), user macros (chained commands), and integration with TPM for plugin management.