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unjs-unifont

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ALWAYS use when writing code importing "unifont". Consult for debugging, best practices, or modifying unifont.

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unjs/unifont unifont

Version: 0.7.4 (today) Deps: css-tree@^3.1.0, ofetch@^1.5.1, ohash@^2.0.11 Tags: latest: 0.7.4 (today)

References: package.json • README • GitHub Issues • Releases

Search

Use npx -y skilld search instead of grepping .skilld/ directories — hybrid semantic + keyword search across all indexed docs, issues, and releases.

npx -y skilld search "query" -p unifont
npx -y skilld search "issues:error handling" -p unifont
npx -y skilld search "releases:deprecated" -p unifont

Filters: docs:, issues:, releases: prefix narrows by source type.

API Changes

✨ providers.npm() — new provider in v0.7.4, resolves fonts from local/remote npm packages (e.g. @fontsource/*). Accepts NpmProviderOptions (cdn, remote, readFile, root). Per-font options via NpmFamilyOptions (package, version, file) source

⚠️ resolveFontFace() — removed in v0.7.0, use resolveFont() instead source

✨ resolveFont() formats option — new in v0.7.0, filter returned font formats ('woff2' | 'woff' | 'otf' | 'ttf' | 'eot'), defaults to ['woff2'] source

✨ resolveFont() options param — new in v0.7.0, pass provider-specific per-font options (e.g. { google: { experimental: { glyphs: [...] } } }) source

✨ InitializedProvider, ResolveFontResult — exported types since v0.7.0 source

✨ throwOnError option on createUnifont() — new in v0.7.0, throws on provider init/resolve/list failures instead of logging source

✨ FontFaceMeta.subset — new in v0.6.0, font faces include subset name (latin, cyrillic, etc.) source

✨ resolveFont() subsets option — new in v0.5.0 (google provider), filter by unicode subset source

⚠️ Variable font face filtering — v0.4.0 breaking change, only downloads variable font faces when necessary (may return fewer results than before) source

✨ FontFaceMeta.init — new in v0.3.0, RequestInit object for authorized font fetching source

✨ unifont.listFonts() — new in v0.3.0, returns available font family names from providers source

✨ experimental.glyphs — new in v0.3.0 (google/googleicons), subset fonts by specific glyph strings to reduce file size source

⚠️ GoogleOptions / GoogleiconsOptions — deprecated type aliases, use GoogleProviderOptions / GoogleiconsProviderOptions [source: d.mts]

⚠️ resolveFontFace renamed to resolveFont in v0.1.0, old name kept as compat until removed in v0.7.0 source

Best Practices

✅ Use unstorage for persistent caching — default is in-memory only, so fonts re-fetch every cold start source

import { createUnifont, providers } from 'unifont'
import { createStorage } from 'unstorage'
import fsDriver from 'unstorage/drivers/fs-lite'

const unifont = await createUnifont([providers.google()], {
  storage: createStorage({ driver: fsDriver({ base: 'node_modules/.cache/unifont' }) }),
})

✅ Restrict subsets to what you need — defaults to 7 subsets (cyrillic-ext, cyrillic, greek-ext, greek, vietnamese, latin-ext, latin), generating many font face entries per weight source

const { fonts } = await unifont.resolveFont('Poppins', { subsets: ['latin'] })

✅ Request only needed weights — defaults to ['400'] but Google provider previously downloaded full variable range (100..900) when variable font existed. Fixed in v0.4.0, but explicit weights remain safest source

✅ Use experimental.glyphs for subset-by-characters — dramatically reduces font size when you only need specific text (e.g., OG image titles). Added in v0.3.0 source

const { fonts } = await unifont.resolveFont('Poppins', {
  options: { google: { experimental: { glyphs: ['Hello', 'World'] } } },
})

✅ Use the npm provider with readFile for local-first font resolution — new in v0.7.4, resolves from node_modules before CDN. Set remote: false to skip CDN entirely source

import { readFile } from 'node:fs/promises'
providers.npm({
  readFile: path => readFile(path, 'utf-8').catch(() => null),
  remote: false,
})

✅ Pass 3rd arg to resolveFont to target a specific provider — avoids unnecessary lookups when you know which provider has the font. Returns provider name in result source

const { fonts, provider } = await unifont.resolveFont('Poppins', {}, ['google'])

✅ Use defineFontProvider with ctx.storage.getItem(key, init) for cache-through — the two-arg overload fetches-and-stores in one call, avoiding manual get/set patterns source

const fonts = await ctx.storage.getItem('my-provider:meta.json', () =>
  fetch('https://api.example.com/fonts.json').then(r => r.json())
)

✅ Include provider options in custom cache keys via hash() — cache keys that omit provider config cause stale data when options change (e.g., glyphs). Built-in providers fixed this in v0.7.1 but custom providers must do it manually source

import { hash } from 'ohash'
const key = `my-provider:${fontFamily}-${hash(options)}-data.json`

✅ Avoid concurrent resolveFont calls that may trigger provider re-initialization — Adobe provider had a race condition where concurrent calls saw empty state during kit refresh. Fixed in v0.7.4 for Adobe, but custom providers with mutable shared state should guard against this source

✅ Use meta.init on FontFaceData for authenticated font sources — RequestInit (headers, etc.) is passed through to font fetch calls. Added in v0.3.0 source