zhijun-dai/dsh-Fonts

Overview

DeepSeek Harness's web UI ships with system font stacks and no webfonts. dsh-Fonts turns fonts into a composable resource:

• Bundled presets: JetBrains Mono + Inter, Fira Code + IBM Plex Sans, and Cascadia Code pairings, all OFL-licensed and shipped with the plugin for offline use (no CORS issues)
• Custom import: enter a family name + woff2 URL in the settings panel to import your own UI/code fonts; the selection persists locally
• Plugin API: a ctx.fonts registry service — other plugins can register or consume font presets via ctx.get("fonts")

Previews

Settings → General → Font (click to expand)

JetBrains Mono + Inter applied

Usage

A dual-face DSH plugin: the host half serves the bundled font files, the browser half provides the registry and the settings row. After installation, pick fonts in Settings → General → Font.

Install:

# GitHub
dsh plugin --profile web add github:zhijun-dai/dsh-Fonts

# local directory (the profile dir is a pnpm workspace root — -w is required)
dsh plugin --profile web add -w /path/to/dsh-Fonts

# npm
dsh plugin --profile web add dsh-fonts

Then restart dsh web.

Switching fonts: Settings → General → Font row — preset cards apply live; "Default" restores the system stacks.

Importing custom fonts: fill in the editor fields (UI font / Code font) and hit Add:

Example — importing Inter Regular from the Fontsource CDN as the UI font:

Family: Inter
woff2 URL: https://cdn.jsdelivr.net/npm/@fontsource/inter@5.3.0/files/inter-latin-400-normal.woff2
Weight: 400 Regular

It applies immediately and survives reloads; re-adding the same family+weight replaces the old entry, and Remove deletes it.

Plugin API

Other plugins consume the font service lazily via ctx.get("fonts") (cross-plugin require is a build error — module imports cannot be used):

// in your plugin's browser half
import type { FontPreset, FontRegistry } from 'dsh-fonts/client'

// register your own font preset
const dispose = ctx.get('fonts')?.register({
  id: 'my-preset',
  ui: ['My Font', '-apple-system', 'sans-serif'],
  code: ['My Mono', 'monospace'],
  faces: [{ family: 'My Font', weight: '400', src: ['https://example.com/my-font.woff2'] }],
})

// subscribe to snapshots
const off = ctx.get('fonts')?.subscribe((snapshot) => {
  console.log(snapshot.activeId, snapshot.revision)
})

Full FontPreset / FontSnapshot / FontRegistry types live in lib/types/client/index.d.ts.

How it works

• The browser half provides the registry to the root context via ctx.provide("fonts", registry) at apply time
• On selection changes it rewrites an injected <style id="dsh-fonts">: @font-face rules plus :root overrides of --dsw-font-family / --ds-font-family-code — the two CSS variables every DSH component consumes via var() (defined in @deepseek-ai/dsh-client-ui-theme's base.css)
• The host half registers a /plugins/dsh-fonts/fonts/* route on ctx.webServer, serving the woff2 files bundled under data/fonts/
• The selection persists in localStorage (dsh-fonts:prefs) and is restored at boot; a selected plugin-registered preset falls back to the default if that plugin is absent

Known limitations

• Some components hardcode an Inter, var(--dsw-font-family) stack (e.g. the workspace browser) — those keep Inter on systems that have it installed
• Bundled fonts are latin subsets (~280KB total); CJK text falls back through the stack tail to system fonts (PingFang SC / Microsoft YaHei)
• Custom imports accept woff2 URLs only (http/https)

Font credits

Bundled fonts are licensed under the SIL Open Font License 1.1; license texts ship in data/fonts/LICENSE-*.txt:

• JetBrains Mono — JetBrains s.r.o.
• Inter — Rasmus Andersson
• Fira Code — The Fira Code Project Authors
• IBM Plex Sans — IBM Corp.
• Cascadia Code — Microsoft

💝 Thanks

• DeepSeek Harness — the plugin architecture and the dsh.client dual-face mechanism
• Fontsource — webfont distribution
• dsh-Catppuccin / dsh-Solarized — the repository conventions this plugin follows