vim-plug is a minimalist Vim/Neovim plugin manager implemented as a single ~4000-line Vim script file (plug.vim) with zero external dependencies. It manages plugins from Git repositories (GitHub, GitLab, Bitbucket, local paths) with support for branch/tag/commit pinning, shallow clones, parallel installation/update (via native Vim8/Neovim job control, Python threading, or Ruby threading), on-demand lazy loading (by command or filetype), post-update hooks (shell commands, Vim commands, or Vim functions), and update review/rollback via PlugDiff. The architecture centers on global dictionaries (g:plugs, g:plugs_order) populated between plug#begin() and plug#end(), with runtimepath reorganization handled by s:reorg_rtp(). Key entry points are the Plug command and :PlugInstall/:PlugUpdate/:PlugClean/:PlugStatus/:PlugDiff/:PlugSnapshot/:PlugUpgrade commands. The codebase demonstrates exceptional craftsmanship in handling cross-platform shell escaping (cmd.exe, PowerShell, POSIX), git URI normalization/comparison, parallel job management with multiple backends, and Vim runtimepath manipulation — all while maintaining flawless backward compatibility with Vim 7.4+ and all Neovim versions.
asyncomplete.vim is a Vim and Neovim plugin that provides asynchronous autocompletion using timers. It allows completion sources to be registered and triggered without blocking the editor. The architecture centers around a core completion engine that manages sources, triggers, and popup menu display. Key features include context-aware completion triggering, support for various change detection mechanisms (autocommands or timers), and a flexible source registration system. The plugin depends only on Vim 8+ or Neovim with timers feature, integrating with Vim's native complete() function for popup menu handling.