Add Turkish interface language

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [1.9.20] - 2026-09-24
 
+### Added
+
+- Turkish (`tr`) interface language: full interface translation, Turkish as a native-language option at registration and in Settings, and Turkish verification, password reset, welcome, and account deletion emails. The dashboard announcement keeps its existing ten locales and falls back to English for Turkish users.
+
 ### Fixed
 
 - Onboarding learning goals now name the selected language in all ten interface languages, with natural wording and a safe display fallback for unrecognized language codes.

backend/app/routers/lessons.py

@@ -119,6 +119,13 @@
         "good_pronunciation": "Pronuntie buna!",
         "target_phrase": "Fraza tinta a fost: {answer}",
     },
+    "tr": {
+        "correct": "Doğru!",
+        "correct_answer": "Doğru cevap: {answer}",
+        "free_write_unavailable": "Yazılı cevap şu anda değerlendirilemedi.",
+        "good_pronunciation": "Telaffuzunuz iyi!",
+        "target_phrase": "Hedef ifade şuydu: {answer}",
+    },
 }
 
 

backend/app/schemas/admin.py

@@ -23,6 +23,7 @@
     "nl",
     "pl",
     "ro",
+    "tr",
 }
 
 

backend/app/schemas/auth.py

@@ -29,6 +29,7 @@ def validate_password_strength(v: str) -> str:
     "nl",
     "pl",
     "ro",
+    "tr",
 }
 
 SUPPORTED_TARGET_LANGUAGES: set[str] = {
@@ -65,6 +66,7 @@ def get_available_languages() -> list[str]:
     "nl",
     "ro",
     "ru",
+    "tr",
 }
 
 VALID_LEARNING_GOALS: set[str] = {

backend/app/services/email_service.py

@@ -122,6 +122,14 @@ def _get_mail_config() -> ConnectionConfig:
         "link_fallback": "\u0415\u0441\u043b\u0438 \u043a\u043d\u043e\u043f\u043a\u0430 \u043d\u0435 \u0440\u0430\u0431\u043e\u0442\u0430\u0435\u0442, \u0441\u043a\u043e\u043f\u0438\u0440\u0443\u0439\u0442\u0435 \u0438 \u0432\u0441\u0442\u0430\u0432\u044c\u0442\u0435 \u044d\u0442\u0443 \u0441\u0441\u044b\u043b\u043a\u0443 \u0432 \u0431\u0440\u0430\u0443\u0437\u0435\u0440:",
         "footer": "\u0415\u0441\u043b\u0438 \u0432\u044b \u043d\u0435 \u0441\u043e\u0437\u0434\u0430\u0432\u0430\u043b\u0438 \u044d\u0442\u043e\u0442 \u0430\u043a\u043a\u0430\u0443\u043d\u0442, \u043f\u0440\u043e\u0441\u0442\u043e \u0438\u0433\u043d\u043e\u0440\u0438\u0440\u0443\u0439\u0442\u0435 \u044d\u0442\u043e \u043f\u0438\u0441\u044c\u043c\u043e.",
     },
+    "tr": {
+        "greeting": "Merhaba {name},",
+        "subject": "FreeLingo hesab\u0131n\u0131z\u0131 do\u011frulay\u0131n",
+        "body": "FreeLingo hesab\u0131n\u0131z\u0131 olu\u015fturdu\u011funuz i\u00e7in te\u015fekk\u00fcr ederiz.<br />L\u00fctfen a\u015fa\u011f\u0131daki d\u00fc\u011fmeye t\u0131klayarak e-posta adresinizi do\u011frulay\u0131n. Bu ba\u011flant\u0131 <strong>24 saat</strong> ge\u00e7erlidir.",
+        "button": "Hesab\u0131m\u0131 do\u011frula",
+        "link_fallback": "D\u00fc\u011fme \u00e7al\u0131\u015fmazsa bu ba\u011flant\u0131y\u0131 kopyalay\u0131p taray\u0131c\u0131n\u0131za yap\u0131\u015ft\u0131r\u0131n:",
+        "footer": "Bu hesab\u0131 siz olu\u015fturmad\u0131ysan\u0131z bu e-postay\u0131 yok sayabilirsiniz.",
+    },
 }
 
 _RESET_I18N: dict[str, dict[str, str]] = {
@@ -205,6 +213,14 @@ def _get_mail_config() -> ConnectionConfig:
         "link_fallback": "\u0415\u0441\u043b\u0438 \u043a\u043d\u043e\u043f\u043a\u0430 \u043d\u0435 \u0440\u0430\u0431\u043e\u0442\u0430\u0435\u0442, \u0441\u043a\u043e\u043f\u0438\u0440\u0443\u0439\u0442\u0435 \u0438 \u0432\u0441\u0442\u0430\u0432\u044c\u0442\u0435 \u044d\u0442\u0443 \u0441\u0441\u044b\u043b\u043a\u0443 \u0432 \u0431\u0440\u0430\u0443\u0437\u0435\u0440:",
         "footer": "\u0415\u0441\u043b\u0438 \u0432\u044b \u043d\u0435 \u0437\u0430\u043f\u0440\u0430\u0448\u0438\u0432\u0430\u043b\u0438 \u0441\u0431\u0440\u043e\u0441, \u043f\u0440\u043e\u0441\u0442\u043e \u0438\u0433\u043d\u043e\u0440\u0438\u0440\u0443\u0439\u0442\u0435 \u044d\u0442\u043e \u043f\u0438\u0441\u044c\u043c\u043e.",
     },
+    "tr": {
+        "greeting": "Merhaba {name},",
+        "subject": "FreeLingo parolan\u0131z\u0131 s\u0131f\u0131rlay\u0131n",
+        "body": "FreeLingo hesab\u0131n\u0131z\u0131n parolas\u0131n\u0131 s\u0131f\u0131rlama iste\u011fi ald\u0131k.<br />Yeni bir parola olu\u015fturmak i\u00e7in a\u015fa\u011f\u0131daki d\u00fc\u011fmeye t\u0131klay\u0131n. Bu ba\u011flant\u0131 <strong>1 saat</strong> ge\u00e7erlidir.",
+        "button": "Parolam\u0131 s\u0131f\u0131rla",
+        "link_fallback": "D\u00fc\u011fme \u00e7al\u0131\u015fmazsa bu ba\u011flant\u0131y\u0131 kopyalay\u0131p taray\u0131c\u0131n\u0131za yap\u0131\u015ft\u0131r\u0131n:",
+        "footer": "Parola s\u0131f\u0131rlama iste\u011finde bulunmad\u0131ysan\u0131z bu e-postay\u0131 g\u00fcvenle yok sayabilirsiniz.",
+    },
 }
 
 _WELCOME_I18N: dict[str, dict[str, str]] = {
@@ -308,6 +324,16 @@ def _get_mail_config() -> ConnectionConfig:
         "button": "\u041f\u0435\u0440\u0435\u0439\u0442\u0438 \u043d\u0430 \u043f\u0430\u043d\u0435\u043b\u044c \u0443\u043f\u0440\u0430\u0432\u043b\u0435\u043d\u0438\u044f",
         "footer": "\u0423\u0441\u043f\u0435\u0445\u043e\u0432 \u0432 \u043e\u0431\u0443\u0447\u0435\u043d\u0438\u0438!",
     },
+    "tr": {
+        "subject": "FreeLingo'ya ho\u015f geldiniz!",
+        "greeting": "Merhaba {name},",
+        "body": "Hesab\u0131n\u0131z haz\u0131r. Ba\u015flamak i\u00e7in \u015funlar\u0131 yapabilirsiniz:",
+        "step1": "<strong>Seviye Tespitine</strong> girin \u2014 mevcut seviyenizi (A1\u2013C2), g\u00fc\u00e7l\u00fc ve zay\u0131f y\u00f6nlerinizi belirler.",
+        "step2": "<strong>\u00c7al\u0131\u015fma Plan\u0131n\u0131z\u0131</strong> olu\u015fturun \u2014 seviyenize ve hedeflerinize g\u00f6re haz\u0131rlanm\u0131\u015f haftal\u0131k bir program.",
+        "step3": "\u0130lk g\u00fcnl\u00fck dersinizi tamamlay\u0131n ve serinizi olu\u015fturmaya ba\u015flay\u0131n.",
+        "button": "Panoma git",
+        "footer": "\u0130yi \u00e7al\u0131\u015fmalar!",
+    },
 }
 
 
@@ -372,6 +398,12 @@ def _get_mail_config() -> ConnectionConfig:
         "body": "\u0412\u0430\u0448 \u0430\u043a\u043a\u0430\u0443\u043d\u0442 FreeLingo \u0443\u0441\u043f\u0435\u0448\u043d\u043e \u0443\u0434\u0430\u043b\u0451\u043d. \u0412\u0441\u0435 \u0432\u0430\u0448\u0438 \u0434\u0430\u043d\u043d\u044b\u0435 \u0431\u044b\u043b\u0438 \u043d\u0430\u0432\u0441\u0435\u0433\u0434\u0430 \u0443\u0434\u0430\u043b\u0435\u043d\u044b \u0441 \u043d\u0430\u0448\u0438\u0445 \u0441\u0435\u0440\u0432\u0435\u0440\u043e\u0432.",
         "footer": "\u0415\u0441\u043b\u0438 \u0432\u044b \u043d\u0435 \u0437\u0430\u043f\u0440\u0430\u0448\u0438\u0432\u0430\u043b\u0438 \u0443\u0434\u0430\u043b\u0435\u043d\u0438\u0435, \u043d\u0435\u043c\u0435\u0434\u043b\u0435\u043d\u043d\u043e \u0441\u0432\u044f\u0436\u0438\u0442\u0435\u0441\u044c \u0441 \u043d\u0430\u043c\u0438.",
     },
+    "tr": {
+        "subject": "FreeLingo hesab\u0131n\u0131z silindi",
+        "greeting": "Merhaba {name},",
+        "body": "FreeLingo hesab\u0131n\u0131z ba\u015far\u0131yla silindi. T\u00fcm verileriniz sunucular\u0131m\u0131zdan kal\u0131c\u0131 olarak kald\u0131r\u0131ld\u0131.",
+        "footer": "Bu silme i\u015flemini siz istemediyseniz l\u00fctfen hemen bizimle ileti\u015fime ge\u00e7in.",
+    },
 }
 
 _CONTACT_I18N: dict[str, dict[str, str]] = {
@@ -465,6 +497,15 @@ def _get_mail_config() -> ConnectionConfig:
         "message_label": "Сообщение",
         "footer": "Отправлено через контактную форму FreeLingo",
     },
+    "tr": {
+        "email_title": "İletişim formu mesajı",
+        "subject_prefix": "[FreeLingo İletişim]",
+        "logo": "FreeLingo: İletişim Formu",
+        "from_label": "Gönderen",
+        "subject_label": "Konu",
+        "message_label": "Mesaj",
+        "footer": "FreeLingo iletişim formu aracılığıyla gönderildi",
+    },
 }
 
 _FEEDBACK_I18N: dict[str, dict[str, str]] = {
@@ -598,6 +639,19 @@ def _get_mail_config() -> ConnectionConfig:
         "cta": "Открыть в панели администратора",
         "footer": "Доска отзывов FreeLingo",
     },
+    "tr": {
+        "email_title": "Yeni geri bildirim gönderildi",
+        "logo": "FreeLingo: Yeni Geri Bildirim",
+        "feature_label": "Özellik isteği",
+        "bug_label": "Hata bildirimi",
+        "feature_subject_prefix": "[Özellik İsteği]",
+        "bug_subject_prefix": "[Hata Bildirimi]",
+        "author_label": "Gönderen",
+        "title_label": "Başlık",
+        "description_label": "Açıklama",
+        "cta": "Yönetim panelinde görüntüle",
+        "footer": "FreeLingo geri bildirim panosu",
+    },
 }
 
 _REVIEW_I18N: dict[str, dict[str, str]] = {
@@ -721,6 +775,18 @@ def _get_mail_config() -> ConnectionConfig:
         "cta": "Открыть в панели администратора",
         "footer": "Модерация отзывов FreeLingo",
     },
+    "tr": {
+        "email_title": "Yeni yorum gönderildi",
+        "subject_prefix": "[Yeni Yorum]",
+        "logo": "FreeLingo: Yeni Yorum",
+        "author_label": "Gönderen",
+        "rating_label": "Puan",
+        "language_label": "Öğrenilen dil",
+        "comment_label": "Yorum",
+        "empty_comment": "Yorum yazılmadı.",
+        "cta": "Yönetim panelinde görüntüle",
+        "footer": "FreeLingo yorum moderasyonu",
+    },
 }
 
 

backend/app/services/language_helpers.py

@@ -135,6 +135,7 @@
     "nl": "Spraaksessie",
     "ro": "Sesiune vocală",
     "ru": "Голосовая сессия",
+    "tr": "Sesli oturum",
 }
 
 _NATIVE_LANGUAGE_NAMES: dict[str, str] = {
@@ -148,6 +149,7 @@
     "nl": "Dutch",
     "ro": "Romanian",
     "ru": "Russian",
+    "tr": "Turkish",
 }
 
 _MONTH_NAMES: dict[str, list[str]] = {
@@ -277,6 +279,20 @@
         "ноября",
         "декабря",
     ],
+    "tr": [
+        "Ocak",
+        "Şubat",
+        "Mart",
+        "Nisan",
+        "Mayıs",
+        "Haziran",
+        "Temmuz",
+        "Ağustos",
+        "Eylül",
+        "Ekim",
+        "Kasım",
+        "Aralık",
+    ],
 }
 
 

backend/tests/test_conversation.py

@@ -577,11 +577,21 @@ def test_voice_session_title_russian() -> None:
     assert " de " not in date_part
 
 
+def test_voice_session_title_turkish() -> None:
+    """Turkish uses its own label and plain 'D Month YYYY' format."""
+    from app.services.language_helpers import voice_session_title
+
+    title = voice_session_title("tr")
+    assert title.startswith("Sesli oturum — ")
+    date_part = title.split(" — ", 1)[1]
+    assert " de " not in date_part
+
+
 def test_voice_session_title_all_supported_languages_produce_nonempty() -> None:
     """Every supported native language must produce a non-empty title."""
     from app.services.language_helpers import voice_session_title
 
-    supported = ["es", "fr", "pt", "de", "it", "pl", "nl", "ro", "ru"]
+    supported = ["es", "fr", "pt", "de", "it", "pl", "nl", "ro", "ru", "tr"]
     for lang in supported:
         title = voice_session_title(lang)
         assert title.strip(), f"Empty title for language '{lang}'"

frontend/src/app/(app)/admin/users/page.tsx

@@ -54,6 +54,7 @@ const LANGUAGES = [
   'nl',
   'ro',
   'ru',
+  'tr',
 ] as const
 
 const PAGE_SIZE = 10

frontend/src/app/(auth)/register/page.tsx

@@ -22,6 +22,7 @@ const LANGUAGES = [
   'nl',
   'ro',
   'ru',
+  'tr',
 ] as const
 
 type SelectedPlan = 'monthly' | 'yearly'

frontend/src/app/layout.tsx

@@ -115,7 +115,7 @@ export default async function RootLayout({
         <script dangerouslySetInnerHTML={{ __html: themeScript }} />
         <script
           dangerouslySetInnerHTML={{
-            __html: `(function(){if(document.cookie.indexOf('LOCALE_DETECTED=')!==-1)return;var m=document.cookie.match(/(^| )NEXT_LOCALE=([^;]+)/);var cl=m?m[2]:null;var bl=(navigator.language||'').split('-')[0].toLowerCase();var s=['es','fr','pt','de','it','pl','nl','ro','ru'];document.cookie='LOCALE_DETECTED=1;path=/;max-age=31536000;SameSite=Lax';if(bl!=='en'&&s.indexOf(bl)!==-1&&cl!==bl){document.cookie='NEXT_LOCALE='+bl+';path=/;max-age=31536000;SameSite=Lax';location.reload()}})();`,
+            __html: `(function(){if(document.cookie.indexOf('LOCALE_DETECTED=')!==-1)return;var m=document.cookie.match(/(^| )NEXT_LOCALE=([^;]+)/);var cl=m?m[2]:null;var bl=(navigator.language||'').split('-')[0].toLowerCase();var s=['es','fr','pt','de','it','pl','nl','ro','ru','tr'];document.cookie='LOCALE_DETECTED=1;path=/;max-age=31536000;SameSite=Lax';if(bl!=='en'&&s.indexOf(bl)!==-1&&cl!==bl){document.cookie='NEXT_LOCALE='+bl+';path=/;max-age=31536000;SameSite=Lax';location.reload()}})();`,
           }}
         />
         {process.env.NEXT_PUBLIC_UMAMI_WEBSITE_ID && (

frontend/src/components/settings/ProfileSection.tsx

@@ -20,6 +20,7 @@ const LANGUAGES = [
   'nl',
   'ro',
   'ru',
+  'tr',
 ] as const
 
 function resizeImage(file: File, maxPx: number): Promise<Blob> {

frontend/src/lib/locales.ts

@@ -13,6 +13,7 @@ export const SUPPORTED_LOCALES = [
   'nl',
   'ro',
   'ru',
+  'tr',
 ] as const
 
 export type Locale = (typeof SUPPORTED_LOCALES)[number]

frontend/src/lib/target-languages.ts

@@ -172,7 +172,7 @@ export function getTargetLanguageTextClass(code: string): string {
 
 export const DEFAULT_TARGET_LANGUAGE = 'en-GB'
 
-const LOCALES_CAPITALIZE_LANGUAGE = new Set(['en', 'de', 'nl'])
+const LOCALES_CAPITALIZE_LANGUAGE = new Set(['en', 'de', 'nl', 'tr'])
 
 export function formatLanguageName(name: string, locale: string): string {
   const lang = locale.split('-')[0]

frontend/tests/app/onboarding-goals-subtitle.test.tsx

@@ -16,6 +16,7 @@ import pl from '../../../messages/pl.json'
 import pt from '../../../messages/pt.json'
 import ro from '../../../messages/ro.json'
 import ru from '../../../messages/ru.json'
+import tr from '../../../messages/tr.json'
 
 const { searchParams, apiFetch } = vi.hoisted(() => ({
   searchParams: new URLSearchParams(),
@@ -31,7 +32,7 @@ vi.mock('@/lib/api', () => ({ apiFetch }))
 
 import OnboardingPage from '@/app/(auth)/onboarding/page'
 
-const catalogs = { de, en, es, fr, it: itMessages, nl, pl, pt, ro, ru }
+const catalogs = { de, en, es, fr, it: itMessages, nl, pl, pt, ro, ru, tr }
 type Locale = keyof typeof catalogs
 
 const spanishSubtitles: Record<Locale, string> = {
@@ -45,6 +46,7 @@ const spanishSubtitles: Record<Locale, string> = {
   pt: 'Idioma: espanhol. Para que você quer usá-lo? Selecione todos os objetivos que se aplicam.',
   ro: 'Limbă: spaniolă. Pentru ce vrei să o folosești? Selectează toate obiectivele care ți se potrivesc.',
   ru: 'Язык: испанский. Для чего ты хочешь его использовать? Выбери все подходящие цели.',
+  tr: 'Dil: İspanyolca. Bu dili ne için kullanmak istiyorsunuz? Uygun olanların hepsini seçin.',
 }
 
 const onIntlError = vi.fn()

frontend/tests/components/ProfileSection.test.tsx

@@ -804,6 +804,7 @@ describe('ProfileSection', () => {
     expect(options).toContain('nl')
     expect(options).toContain('ro')
     expect(options).toContain('ru')
+    expect(options).toContain('tr')
   })
 
   it('renders all ui locale options', () => {
@@ -820,6 +821,7 @@ describe('ProfileSection', () => {
     expect(options).toContain('nl')
     expect(options).toContain('ro')
     expect(options).toContain('ru')
+    expect(options).toContain('tr')
   })
 
   // ── Avatar upload buttons ───────────────────────────────────

frontend/tests/i18n/admin-messages.test.ts

@@ -9,8 +9,9 @@ import pl from '../../../messages/pl.json'
 import pt from '../../../messages/pt.json'
 import ro from '../../../messages/ro.json'
 import ru from '../../../messages/ru.json'
+import tr from '../../../messages/tr.json'
 
-const locales = { de, es, fr, it: itMessages, nl, pl, pt, ro, ru }
+const locales = { de, es, fr, it: itMessages, nl, pl, pt, ro, ru, tr }
 
 describe('admin i18n messages', () => {
   it('keeps admin namespace keys in sync across locales', () => {

messages/de.json

@@ -1234,6 +1234,7 @@
     "nl": "Niederländisch",
     "ro": "Rumänisch",
     "ru": "Russisch",
+    "tr": "Türkisch",
     "myLanguages": "Meine Sprachen",
     "addLanguage": "Sprache hinzufügen",
     "selectLanguage": "Wähle die Sprache, die du lernen möchtest",

messages/en.json

@@ -1234,6 +1234,7 @@
     "nl": "Dutch",
     "ro": "Romanian",
     "ru": "Russian",
+    "tr": "Turkish",
     "myLanguages": "My Languages",
     "addLanguage": "Add new language",
     "selectLanguage": "Select the language you want to learn",

messages/es.json

@@ -1234,6 +1234,7 @@
     "nl": "Neerlandés",
     "ro": "Rumano",
     "ru": "Ruso",
+    "tr": "Turco",
     "myLanguages": "Mis idiomas",
     "addLanguage": "Añadir idioma",
     "selectLanguage": "Selecciona el idioma que quieres aprender",

messages/fr.json

@@ -1234,6 +1234,7 @@
     "nl": "Néerlandais",
     "ro": "Roumain",
     "ru": "Russe",
+    "tr": "Turc",
     "myLanguages": "Mes langues",
     "addLanguage": "Ajouter une langue",
     "selectLanguage": "Choisissez la langue que vous voulez apprendre",

messages/it.json

@@ -1234,6 +1234,7 @@
     "nl": "Olandese",
     "ro": "Rumeno",
     "ru": "Russo",
+    "tr": "Turco",
     "myLanguages": "Le mie lingue",
     "addLanguage": "Aggiungi lingua",
     "selectLanguage": "Seleziona la lingua che vuoi imparare",

messages/nl.json

@@ -1234,6 +1234,7 @@
     "nl": "Nederlands",
     "ro": "Roemeens",
     "ru": "Russisch",
+    "tr": "Turks",
     "myLanguages": "Mijn talen",
     "addLanguage": "Taal toevoegen",
     "selectLanguage": "Kies de taal die je wilt leren",

messages/pl.json

@@ -1234,6 +1234,7 @@
     "nl": "Niderlandzki",
     "ro": "Rumuński",
     "ru": "Rosyjski",
+    "tr": "Turecki",
     "myLanguages": "Moje języki",
     "addLanguage": "Dodaj język",
     "selectLanguage": "Wybierz język, którego chcesz się uczyć",

messages/pt.json

@@ -1234,6 +1234,7 @@
     "nl": "Neerlandês",
     "ro": "Romeno",
     "ru": "Russo",
+    "tr": "Turco",
     "myLanguages": "Meus idiomas",
     "addLanguage": "Adicionar idioma",
     "selectLanguage": "Selecione o idioma que deseja aprender",

messages/ro.json

@@ -1234,6 +1234,7 @@
     "nl": "Olandeză",
     "ro": "Română",
     "ru": "Rusă",
+    "tr": "Turcă",
     "myLanguages": "Limbile mele",
     "addLanguage": "Adaugă limbă",
     "selectLanguage": "Alege limba pe care vrei să o înveți",