The interface speaks Slovak

969 strings, an instance default and a per-person choice, and no half-done corner:
the admin prose is translated too. Design and reasoning: LLeMbas.wiki/Translations.

KEYED BY THE ENGLISH SENTENCE

A missing entry renders the key, which is the English -- so an untranslated string
looks as it always did, an English instance is byte-for-byte 1.6.0, and a
half-finished catalogue is a half-translated page rather than a page of dotted key
names. The cost is that editing an English sentence orphans its translation
silently, which is what tests/test_translations.py asserts in both directions.

No gettext: .po -> .mo is a build step and this project does not have one.

A JINJA GLOBAL, AND THEREFORE A CONTEXTVAR

`t()` is a global for the reason `brand` already documents -- render() is bypassed
by 25 TemplateResponse calls and 8 get_template().render() calls, the latter being
the SSE frames, which have no Request at all. A global is bound once at import and
the language is per person, so the active language is a ContextVar set per request.

🚨 `get_current_user` had to become `async def`. FastAPI runs a sync dependency in a
threadpool, and anyio copies the context in and discards it on the way out -- so
the language was set where nothing could see it and every page rendered in the
instance's language whatever anybody had chosen, with no error anywhere.

NOT TRANSLATED, ON PURPOSE

Everything a model reads: the 60 prompt fragments, and the dates in harness.py,
schedule/runner.py and schedule/compile.py. Only `i18n.stamp` is localised, and
only where a person reads it -- with the *format* translatable as well as the
words, because "26. septembra 2026" is a different pattern rather than the same one
with different words in it. A process locale is not an option: global, not
thread-safe, two people's pages at once.

A second fragment telling models to answer in the reader's language was written
during this work and removed: `core.style` has said it since long before, and
test_an_empty_override_turns_a_fragment_off caught the duplicate.

THE BULK PASS

1213 sites wrapped by a one-off script that only touched patterns it could not
misread. It got three wrong in a way that mattered -- `t('…')` inside `attr="…"`
where the sentence held an apostrophe, closing the Jinja string and 500ing two
pages whose partials no test renders. tests/test_translations.py now compiles all
110 templates. It also wrapped the product's own name, an SSH key header, a
keystroke hint and an example URL, all taken back out: a string is not
translatable just because it is a string.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/lembas/main.py

@@ -49,6 +49,7 @@ from lembas.api.deps import RedirectToLogin, is_htmx, login_redirect
 from lembas.config import settings
 from lembas.db.session import init_db
 from lembas.services.library import indexing
+from lembas.web import i18n
 from lembas.web.templating import STATIC_DIR, render
 
 log = logging.getLogger("lembas")
@@ -177,6 +178,15 @@ def create_app() -> FastAPI:
 
     app.mount("/static", StaticFiles(directory=str(STATIC_DIR)), name="static")
 
+    # The language every request starts in. A `ContextVar` is per task, and a task
+    # is reused between requests -- so without resetting it here, a signed-out page
+    # would inherit whichever person was served last on that worker. The user's own
+    # choice is applied later, by `get_current_user`, where they are already known.
+    @app.middleware("http")
+    async def _language(request, call_next):
+        i18n.activate(i18n.instance_default())
+        return await call_next(request)
+
     # One place that notices a library record changing, rather than a call in
     # each of the ten writers that touch those tables. Idempotent, because the
     # factory is called per test. See services/library/indexing.py:install.