Forgejo theme

Dataverket's light, dark and auto themes for Forgejo, generated from the design system in the org repo, which task clones for you.

What it gives you

• A branded forge without a fork. Themes, logo, favicon and landing page copy, all through Forgejo's custom path. No patched binary, no forked templates.
• Palette that cannot drift. Every colour is generated from the design system's tokens; change the palette there and regenerate.
• The same fonts as every other Dataverket surface. Inter and JetBrains Mono, served from the instance.
• Mirrors work. Nothing names the host: internal links are relative and the copy does not mention the instance.

Try it

brew install forgejo go-task

task              # list the targets
task dev          # fetch, generate, run on http://localhost:3000
task reset        # throw the instance away and start over

task dev clones the design system into vendor/, regenerates, then runs Forgejo against this directory. Everything it writes lives in .dev/ and vendor/, both gitignored; no real instance is touched.

Everything under public/ and options/ is generated. Edit make-theme.py, not its output. That is the one way this repo differs from a hand-authored custom directory.

dataverket-auto follows the operating system and is the default. dataverket-light and dataverket-dark are fixed. Pick per user under Settings -> Appearance, or set DEFAULT_THEME.

Use it on a real instance

Point Forgejo at this directory and list the themes:

[ui]
DEFAULT_THEME = dataverket-auto
THEMES = dataverket-auto,dataverket-light,dataverket-dark

forgejo web --custom-path /path/to/forgejo-theme

Run task build on the target first: the locale is patched against the Forgejo version installed there, and is not committed.

Use it on Dataverket's own instance

git.dataverket.org runs on fabrikk-infra, which points a Flux GitRepository and Kustomization at this repo (apps/forgejo/theme.yaml). This repo's own kustomization.yaml turns the committed public/assets/{css,img,fonts} into three ConfigMaps, which the forgejo HelmRelease mounts straight over Forgejo's own copies. Push to main, and the running pod serves the change within one Flux reconcile - no rebuild, no restart.

options/locale/ can't travel that way: it has to be extracted from the exact Forgejo binary version running there, which git alone can't provide. fabrikk-infra's forgejo-theme-locale CronJob (apps/forgejo/theme-locale.yaml) handles it separately, re-fetching make-theme.py and re-running locale() against the pinned image on a schedule. Because Forgejo loads locale strings at startup rather than serving them from disk, a copy change only reaches visitors after the pod's next restart.

What lives here

File	What it is
make-theme.py	The source. Generates everything below.
Taskfile.yaml	Fetch, generate, run.
public/assets/css/	The three themes. Generated.
public/assets/img/	Logo, favicon, touch icon. Generated; the PNGs need a headless browser and are left alone without one.
public/assets/fonts/	Inter and JetBrains Mono. Copied from the design system.
options/locale/	Patched en-US. Generated, gitignored.

The themes

Each imports Forgejo's own and overrides variables only:

@import url("/assets/css/theme-forgejo-light.css");

Four groups are overridden, and nothing else:

• --zinc-* and --steel-* - the neutral scales everything derives from. Forgejo's lightness per step is kept; hue and saturation become the Dataverket slate. Both are needed: light derives from zinc, dark from steel, and the dark theme does not define zinc at all.
• --color-primary* - the accent ramp, alphas, hover and active.
• --color-red* and --color-error-* - the flag red.
• --fonts-proportional and --fonts-monospace - Inter and JetBrains Mono.

dataverket-auto carries both sets: light at :root, dark behind @media (prefers-color-scheme: dark), the same shape as Forgejo's own auto theme.

The dark accent is not the design system's accent token. That one is a surface colour, and a button filled with it reads as disabled. Dark uses the brand navy's hue and saturation lifted to L=0.50: 3.5:1 against the dark surface, 5.1:1 for the white label.

Flag red runs through the whole red family. The design system keeps brand1 for identity only, because it sits close to danger. Here the navy and the red together are the identity, so every red Forgejo shows is the same one.

The logo

File	What it is
logo.svg	Shadows Forgejo's own. Navy.
logo-dataverket-light.svg / -dark.svg	One per theme.
favicon.svg	Carries its own prefers-color-scheme switch.
*.png	Raster fallbacks. Forgejo asks for favicon.png; iOS wants a touch icon.

Forgejo draws the logo at 30 px in the navbar and 220 px on the landing page, from one square file. The design system's shapes are re-wrapped into a 212x212 box at 76% fill, so rounded crops cannot clip it.

Forgejo renders the logo as <img>. CSS cannot reach inside one, and fill="currentColor" does nothing there, so each theme swaps the file with content: url(...). The favicon cannot use that - it sits on browser chrome the page theme cannot reach - so it carries a media query instead.

The landing page

Forgejo replaces options/locale, it does not merge it. A nine-key override leaves every other string missing and the server will not start.

make-theme.py extracts the 3300-line en-US from the installed binary and patches the [startpage] section. It is gitignored, so it always matches the version running rather than drifting.

Two strings take link arguments - install_desc three, license_desc two

• and Go prints %!(EXTRA ...) on the page if they go unused. license_desc is handed the Forgejo and contributing URLs, so the free-software copy lives in that card and uses both. install_desc gets three download URLs with no use here; they are swallowed by a comment.

Copy lives in STARTPAGE at the top of make-theme.py.

Regenerating

task build        # fetches the design system if needed, then generates
task update       # pull the latest design system

DESIGN_BUILD points the generator at a working copy instead of the clone.

Three steps degrade rather than fail, each with a note: the locale needs the forgejo binary, the PNGs need a headless browser, and refreshing the fonts needs task vendor to have run in the design system. The committed copies are kept when a step is skipped.

Known limits

• Forgejo 16.0.5 lists custom themes by slug. There is no theme-display-name parsing and no locale key, so the switcher reads dataverket-auto. The gitea-theme-meta-info block is there for forward compatibility.
• Images are served without a cache-busting query, unlike the CSS. A visitor who saw the old logo keeps it for up to six hours.
• Two filenames are ours, not Forgejo's: logo-dataverket-light.svg and -dark.svg, which the themes swap between. Everything else shadows a file Forgejo already ships.

Reference

• Blender's gitea-custom
  • the same custom-path mechanism, with a standalone theme rather than an import.