The P0 foundation every other zone builds on: the locale/strings surface on ThemeConfig, the value types, the render-scoped LocaleContext slice, the resolver helpers, and the per-key fallback precedence. Nothing else in SPEC-035 can land without this.
Tracking started Jul 17 — check back for trends.
locale?: string (BCP 47, default 'en') and strings?: Record<string, LocalizedValue> to ThemeConfig (packages/transform/src/types.ts).LocalizedValue = string | PluralMap and PluralMap = Partial<Record<Intl.LDMLPluralRule, string>>.LocaleContext { locale: string; strings: Record<string, LocalizedValue> } — the render-scoped slice threaded into consumers. It must never be module-global mutable state (SPEC-035 forward-compatibility constraint for future multi-locale builds).resolveLocaleString(ctx, key, fallback) and resolvePluralString(ctx, key, count, fallback) (via Intl.PluralRules, {n} interpolation).strings → owning package's shipped locale bundle (with de-AT→de region-strip) → English literal. First-match, per key — not a deep merge.ThemeConfig.locale + strings and the LocalizedValue / PluralMap types exist and compile across dependents.LocaleContext is defined; resolveLocaleString / resolvePluralString implemented with tests.locale / strings set, transform output is byte-identical to today.Completed: 2026-07-17
Branch: claude/milestone-v0-29-0-stzywk
packages/transform/src/i18n.ts: LocalizedValue/PluralMap types, render-scoped LocaleContext, resolveLocaleString/resolvePluralString (Intl.PluralRules, {n} interpolation), localeFallbackChain (BCP-47 region-strip), selectLocaleBundle, mergeLocaleStrings, normalizeLocale, createLocaleContext, EN_LOCALE_CONTEXT.ThemeConfig.locale + ThemeConfig.strings in packages/transform/src/types.ts.packages/transform/src/index.ts.packages/transform/test/i18n.test.ts covering scalar/plural resolution, region-strip fallback, per-key precedence, missing-key → English.