Core Plugins

HUME ships a some plugins under the core: namespace — a plugin and grammar manager, language server support, and a few keymap alternatives. None of them load automatically. Nothing runs until you ask for it in your init.scm, so a default HUME is exactly what you see.

There are two ways to bring a plugin in:

(declare-plugin "core:plum")    ; lazy — loads the first time you use it
(load-plugin "core:plum")       ; eager — loads at startup

Plugins that rebind keys have to be loaded eagerly, since their bindings must exist before you press anything. Those are marked below. See Plugins for the difference in detail.

core:plum

PLUM — the HUME PLUgin Manager — installs and updates third-party plugins from GitHub, and installs the tree-sitter grammars that power syntax highlighting.

(declare-plugin "core:plum")

PLUM never installs anything on its own: the commands below do the work when you run them.

Command	Effect
:plum-install	Install all declared plugins not yet on disk
:plum-cleanup	Remove on-disk plugins no longer declared
:plum-update	Pull the latest version of every installed third-party plugin
:plum-list	Show declared / installed / orphan / missing plugins
:plum-install-grammar <lang>	Install and compile one grammar
:plum-ensure-grammars	Install every grammar you have a language for
:plum-list-grammars	Show the grammar catalog and what's installed
:plum-cleanup-grammars	Remove compiled grammars you no longer need

Leaving PLUM out removes these commands — and, since PLUM is also what registers installed grammars at startup, syntax highlighting along with them. See Syntax Highlighting for the grammar workflow.

core:lsp

Language server support: hover, go-to-definition, references, diagnostics, rename, formatting, code actions, signature help, completions, and inlay hints. It also downloads and manages the servers themselves (:lsp-install, :lsp-uninstall, :lsp-servers), and the running processes (:lsp-status, :lsp-stop, :lsp-restart).

(declare-plugin "core:stdlib")
(declare-plugin "core:lsp")

Requires core:stdlib. Declared lazily like this, it wakes up on the first buffer with a detected language, or the first :lsp-* command you type.

See Language Servers for setup, the full command and key tables, and settings.

core:steel-server

Registers a language server for Scheme buffers (.ss/.scm/.sld) — which includes your own init.scm and plugin files, so you get hover, diagnostics, and completion while editing your HUME config. Requires core:lsp, which provides the editor-side features that make a registered server useful.

(declare-plugin "core:stdlib")
(declare-plugin "core:lsp")
(declare-plugin "core:steel-server")

Declared lazily like this, it activates on the first Scheme buffer or the first time you run :steel-server-install.

This is a temporary plugin. The underlying server isn't in HUME's regular server catalog yet, so it can't be installed through :lsp-install like other servers. Once it lands upstream, HUME's catalog will pick it up automatically and this plugin will be retired.

Command	Effect
:steel-server-install	Install the Scheme language server and register it for Scheme buffers

Installing requires cargo — install Rust from rustup.rs first. See Language Servers for the general LSP workflow.

core:pickers

Fuzzy file and buffer finders: g f opens a file picker (git-index-backed inside a repo, fd-backed otherwise), g b opens a buffer switcher.

(load-plugin "core:pickers")

Must be loaded eagerly. See Fuzzy Finder for the file-source chain, keys, and buffer display details.

core:vim-keybind

Vim muscle memory: $, ^, 0, G (last line), C and D (change/delete to end of line), Ctrl+6 (alternate file, kitty only), and o in Extend mode to swap the selection's ends.

(load-plugin "core:stdlib")
(load-plugin "core:vim-keybind")

Must be loaded eagerly, and core:stdlib must be loaded eagerly before it.

By default ('smart), C is context-sensitive: on a bare cursor it changes to end of line as in vim, but with a real selection it runs HUME's own copy-selection-on-next-line, so that command stays reachable. Change this with #:config:

(load-plugin "core:vim-keybind" #:config (hash "change-to-eol" 'on))

'on always changes to end of line; 'off leaves C alone. Both of those skip the selection check, so with them core:stdlib isn't needed at all.

core:helix-surround

Helix-style surround keys: m s wraps the selection, m d deletes a surrounding pair, m r replaces one.

(load-plugin "core:helix-surround")

Must be loaded eagerly. Note that it takes over m s — which by default selects a surrounding pair — and removes m w, so wrapping lives on m s alone once it's loaded.

core:classic-paste

GUI-style paste, if you'd rather not have p choose a source for you: p / P paste the kill ring, Ctrl+V / Ctrl+Shift+V paste the system clipboard (Ctrl+Shift+V needs the kitty protocol).

(load-plugin "core:classic-paste")

Must be loaded eagerly.

core:stdlib

A toolkit of small helpers that other plugins build on, rather than something you use directly. Several bundled plugins depend on it, so load it before them:

(load-plugin "core:stdlib")

If you're writing a plugin yourself, see Plugins for what it offers.