gtheme — a GNOME theme manager

Download, apply, switch, and author full-desktop GNOME themes from a single palette — wallpaper, GTK, terminal, prompt, editor, monitor, the lot. One declarative manifest per theme; gtheme snapshots everything it touches, so gtheme restore always brings back your exact pre-gtheme desktop. No hand-written undo scripts, no half-reverted configs.

gtheme                    # ← just run it: an interactive arrow-key menu
gtheme apply magma        # back up current state, apply the MAGMA theme
gtheme diff magma         # preview what a theme would change, first
gtheme restore            # revert to the desktop you had before gtheme

Requirements

• GNOME 47+ (Wayland or X11) — on other desktops gtheme warns and asks before touching anything
• Python 3.11+ with jinja2 and pydantic (v2)
• gsettings/dconf (ship with GNOME), git only for installing themes from URLs

Install

Easiest — pipx (works on every distro, no dependency puzzles):

sudo apt install pipx        # Ubuntu/Debian   (Fedora: sudo dnf install pipx)
pipx install gtheme          # or, before the PyPI release:
pipx install git+https://github.com/blyatiful1/gtheme

From a checkout (contributors, or if you prefer git):

git clone https://github.com/blyatiful1/gtheme ~/gtheme
~/gtheme/install.sh --pip    # checks deps; sets up a private venv if needed

The installer explains anything that's missing (including the exact commands for apt/dnf/pacman) and how to put ~/.local/bin on your PATH if it isn't. Keep the cloned folder around — the installed command runs from it.

Distro packages for the dependencies, if you'd rather use them:

sudo apt install python3-jinja2 python3-pydantic   # Debian 13+/Ubuntu 25.04+ (older apt ships pydantic v1 — use pipx there)
sudo dnf install python3-jinja2 python3-pydantic   # Fedora
sudo pacman -S python-jinja2 python-pydantic       # Arch (a PKGBUILD is also included)

The interactive menu

Run gtheme with no arguments and you get a full-screen arrow-key menu that reaches every command — apply/switch with dry-run preview, restore, browse, author (new/build/capture), and manage (install/update/remove/export/ validate/search). Theme pickers show live palette swatches and a description panel; the header wears your applied theme's accent colours.

Move with ↑/↓ (or j/k), enter/→ to select, q/esc/← to go back, 1-9 to pick directly. It's pure stdlib — no rich, no curses — runs on the alternate screen (your scrollback survives), adapts to any terminal size, and honours NO_COLOR. Without a TTY it degrades to a plain numbered prompt; set GTHEME_PLAIN=1 or pass --plain to force that mode on a real terminal too (screen-reader friendly).

How a theme works

A theme is a directory with a declarative theme.toml:

[meta]
name = "magma"
title = "MAGMA — Obsidian Flow"

[palette]                       # or a separate palette.toml
bg = "#0D0A0F"
accent = "#FF6D3A"
# ...

[[files]]                       # component tag drives --only and per-file backup
component = "gtk"
src  = "files/gtk/gtk.css"
dest = "~/.config/gtk-4.0/gtk.css"

[[settings]]                    # gsettings or dconf; value is GVariant text
component = "desktop"
backend = "gsettings"
key   = "org.gnome.desktop.interface accent-color"
value = "'orange'"

[[settings]]                    # {{ runtime }} tokens resolve per-machine
component = "terminal"
backend = "dconf"
key   = "/org/gnome/Ptyxis/Profiles/{{ ptyxis_default_profile }}/palette"
value = "'Magma'"

[[hooks]]                       # optional scripts for the weird 10%
event = "post"
component = "extras"
script = "hooks/setup.sh"
optional = true

Layout:

themes/<name>/
  theme.toml        palette.toml
  files/            # sources referenced by [[files]].src
  assets/           # non-installed extras (svg sources, etc.)
  hooks/            # scripts referenced by [[hooks]]

schema/theme.schema.json gives you editor validation/completion for theme.toml (taplo / the Even Better TOML VS Code extension).

Backup & restore (the safety net)

The first time gtheme touches a file or a settings key, it snapshots the prior value into a pristine baseline under ~/.local/state/gtheme/. Apply and switch as much as you like — gtheme restore always returns the system to the state it had before gtheme first ran: files the themes introduced are removed (including now-empty directories), overwritten files and settings come back byte-for-byte. After a successful full restore the baseline is consumed, so the next apply re-snapshots your (possibly edited) configs instead of pinning stale copies.

Concurrent runs are locked out, interrupted applies stay recoverable, and apply --only <component> layers a single component without un-theming the rest of your desktop.

{{ runtime }} tokens (ptyxis_default_profile, home) resolve at apply time, so manifests committed to the repo are portable across machines.

Authoring: a palette becomes a desktop

gtheme new ocean --from magma    # scaffold, seeding the palette from magma
$EDITOR ~/.local/share/gtheme/themes/ocean/palette.toml
gtheme build ocean               # render alacritty/ptyxis/btop/micro/gtk from it
gtheme apply ocean --dry-run     # preview every file + setting change
gtheme apply ocean

build renders the components listed in [build].managed from shared Jinja templates (src/gtheme/templates/), with filters like lighten, darken, mix, alpha. Define the structural roles and the 6 ANSI hues; brights and surfaces are derived when omitted.

Palette roles

role	required?	notes
bg, fg, accent	recommended	everything else can derive from these
surface1..3, fg_dim, fg_bright, accent_bright, selection, comment, cursor	derived	override to taste
red green yellow blue magenta cyan	recommended	ANSI hues; bright_* variants derive
ansi_black, ansi_white, bright_black, bright_white	derived

Other [[files]] fields worth knowing: template = true runs the source through {{ }} substitution at apply time; mode = "755" sets permissions; a pre hook that fails aborts the whole apply, optional = true hooks only warn. If your palette is dark, set the color-scheme gsetting to 'prefer-dark' — your users may be in light mode.

Already themed your desktop by hand? Freeze and share it:

gtheme capture mydesk            # snapshot the FULL live look into a theme
gtheme export mydesk             # bundle it into a shareable mydesk.zip
gtheme install mydesk.zip        # (on the other machine)

capture records the GNOME interface settings (accent, color-scheme, icon/GTK/cursor themes, fonts), the wallpaper (bundled and made portable), terminal/prompt/shell/monitor/editor configs and the theme files they reference (Ptyxis palettes, btop themes, alacritty imports), plus every supported extension's settings. It warns you about anything that looks like a secret or a machine-specific path before you share the result.

Commands

command	what it does
list / search <q> [--remote]	browse locally, or search the online collection
install <name|path|.zip|git-url>	install a theme (collection, local dir, .zip, or repo)
remove <name> / update [name]	uninstall, or refetch from the recorded origin
diff <name> / apply <name> --dry-run	preview changes without writing
apply <name> [--only c1,c2] [-y]	apply (--no-sudo / --no-hooks to skip hooks)
switch <name>	alias of apply — the pristine baseline is kept either way
restore [--only c1,c2] [--wipe] [-y]	revert to the pre-gtheme state
current / validate [name]	show the active theme; check a manifest
new <name> [--from base] / build <name>	author from a palette
capture <name> / export <name>	freeze the live desktop; bundle a .zip
publish <name> / index	add to the collection + regenerate its index

Global flags: --version, --verbose, --plain. Commands that change things take -y/--yes (assume yes — non-interactive/CI use). Run gtheme <command> --help for the details.

Security & consent

Themes can ship [[hooks]] (arbitrary shell scripts) and write files across your home directory, so gtheme treats anything you downloaded as untrusted:

• Every hook is previewed and individually confirmed before it runs; --yes approves them all (only for themes you trust). Trusted, non-sudo hooks from your own local themes run without prompts.
• Themes installed from a git URL or .zip are marked untrusted; their hooks are denied by default in non-interactive runs.
• File destinations are confined to your home directory; theme sources are confined to the theme's own directory; exports refuse to follow symlinks out of the theme. Path escapes (/etc/..., ~/../...) are refused.
• --insecure (allow http:// origins) and --allow-unsafe (install despite failed validation) exist for development; leave them off.

Found a boundary escape? See SECURITY.md.

The collection

	theme
	hyperclass	HYPERCLASS — Gilded Void: first class aboard a starliner; champagne brass trim on deep-space ink, ivory starlight, one vein of ice. Ships an ASCII orrery that is a working clock (orrery), a truecolor hyperspace jump (warp), a self-printing art-deco boarding pass (boarding), three procedural wallpapers on a slow crossfade, and a champagne hexagon Burn-My-Windows profile
	magma	MAGMA — Obsidian Flow: obsidian glass, molten orange, lava gold, one cool teal vein. Ships a live lava-lamp fluid sim for the terminal (lavalamp), plus embers, erupt and thermal, and three procedural wallpapers on a slow crossfade

Contribute yours: gtheme publish <name> prints the exact PR steps, and CONTRIBUTING.md has the submission checklist (validate passes, original/licensed assets, no machine-specific paths).

Troubleshooting

• gtheme: command not found after install — ~/.local/bin isn't on your PATH; the installer prints the exact line to add for your shell.
• pydantic 1.x errors on Debian/Ubuntu — your apt ships pydantic v1; install with pipx or ./install.sh --pip instead.
• Not on GNOME? — gtheme themes GNOME; it will warn you and ask before writing anything on KDE/XFCE.
• Something looks wrong after applying — gtheme restore returns your desktop to its pre-gtheme state; then please open an issue with the template's environment details.

License

MIT — see LICENSE. Copyright (c) 2026 blyatiful1.