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+# RFC-0011: Language data comes from craft-i18n
+
+Spelling and hyphenation work for English and little else, and each app
+does it differently. WordCraft and DesignCraft embed Moby, PhotoCraft
+embeds SCOWL, DesignCraft and craft-text enable a few `hypher` languages,
+DeckCraft and GridCraft read only system dictionaries, and the other apps
+have none. Two apps check the same word differently. About 25 open issues
+ask for a missing language, and about 10 more report that a hand-installed
+dictionary isn't found.
+
+## Decision
+
+- craft-i18n holds the suite's **Language data**: spelling dictionaries
+  (Hunspell `.aff`/`.dic`), hyphenation patterns (TeX) and the suite word
+  list. Upstream files are unchanged, pinned by commit and sha256, and
+  checked by CI. The code that reads them stays in craft-libs:
+  craft-proof for spelling, craft-text for hyphenation
+  (craft-i18n ADR 0002, 0005).
+- English (en-US, en-GB) is embedded in every app from `CRAFT_I18N_DIR`,
+  the same input as the catalogs. A build without it still builds.
+- Other languages are downloaded only after the user opts in, through
+  the font store and its single consent switch (craft-libs#223). Until
+  that ships, apps fall back to system Hunspell dictionaries. A
+  **Language build** (`CRAFT_LANGUAGES=de,fr`) embeds chosen languages
+  for packagers and managed installs.
+- What an app gets is fixed by its Pin, never `main`.
+- Third-party data is allowed under craft-i18n ADR 0004's licence table.
+  GPL-only data is download-only. Nothing copyleft ships until a
+  maintainer signs the table off.
+- Apps stop carrying their own word lists, patterns and `hypher` features.
+  Each app drops its copy in the same PR that adopts craft-i18n's data,
+  and lists the spelling changes as parity exceptions.
+
+## What this asks of each app
+
+- Read spelling through craft-proof and hyphenation through craft-text.
+- Add no new dictionary, word list or pattern file of its own. Fixes go
+  upstream, and the app moves its pin.
+- Keep User words as they are today. They are app state, not Language data.
+
+## Not in this RFC
+
+Thesaurus, grammar, autocorrect, the shared User word store, the download
+UI (craft-libs#223) and ICU4X segmentation data.
+
+## Open
+
+- Licence table sign-off (craft-i18n ADR 0004).
+- craft-libs#223 decisions 1 (network) and 4 (index hosting), which
+  block downloads.
+- craft-text (aiongg) and craft-proof (brzuchal) owners agreeing to read
+  Language data from craft-i18n.
+- Should any of "Not in this RFC" be included? The thesaurus is the
+  likeliest candidate. Including it means a format (e.g. MyThes
+  `.dat`/`.idx`), its licences (many are LGPL or GPL), and a reader in
+  craft-libs, which doesn't exist yet. It also means updating craft-i18n's
+  spec, glossary and ADR 0005, which exclude it today. Each item can
+  instead come back as its own RFC.
+
+## References
+
+- craft-i18n `plans/language-data-spec.md`,
+  `plans/2026-10-23-plan-language-data.md`
+- craft-i18n `docs/adr/0002`, `0004`, `0005`; `GLOSSARY.md`
+- craft-i18n#8, craft-libs#18, #19, #31, #223
+
+The craft-i18n spec, plan, ADRs 0004 and 0005 and the glossary changes
+are local to benandez for now and not yet pushed; links follow once they
+are.