diff --git a/app/Devnull/Account.php b/app/Devnull/Account.php
index 2291742..1aa0b9e 100644
--- a/app/Devnull/Account.php
+++ b/app/Devnull/Account.php
@@ -36,6 +36,8 @@ final class Account
 
     private const string TermsKey = 'devnull.terms-to-accept';
 
+    private const string TranslationKey = 'devnull.translation-preferences';
+
     public function user(): ?User
     {
         $attributes = Cache::get(self::CacheKey);
@@ -45,6 +47,10 @@ public function user(): ?User
 
     public function remember(User $user): void
     {
+        if ($this->user()?->id !== $user->id) {
+            app(ResponseCache::class)->forgetGeneratedTranslations();
+        }
+
         Cache::forever(self::CacheKey, $user->toArray());
     }
 
@@ -192,6 +198,62 @@ public function rememberTimezone(?string $timezone): void
         Cache::forever(self::TimezoneKey, $timezone);
     }
 
+    /** The account language preference, or null to follow this phone. */
+    public function translationLanguage(): ?string
+    {
+        $language = Cache::get(self::TranslationKey, [])['translation_language'] ?? null;
+
+        return is_string($language) && $language !== '' ? $language : null;
+    }
+
+    /** Cached translations display automatically unless the account explicitly opts out. */
+    public function automaticTranslation(): bool
+    {
+        return (Cache::get(self::TranslationKey, [])['automatic_translation'] ?? true) !== false;
+    }
+
+    /**
+     * Supported choices last supplied by settings; empty on older backends without translation settings.
+     *
+     * @return list<array{code: string, name: string, native_name: string}>
+     */
+    public function translationLanguages(): array
+    {
+        return Cache::get(self::TranslationKey, [])['translation_languages'] ?? [];
+    }
+
+    /**
+     * Partial settings answers must not reset preferences they don't carry.
+     *
+     * @param  array<string, mixed>  $settings
+     */
+    public function rememberTranslationSettings(array $settings): void
+    {
+        $kept = Cache::get(self::TranslationKey, []);
+
+        if (array_key_exists('translation_language', $settings)) {
+            $language = $settings['translation_language'];
+
+            if ($language !== ($kept['translation_language'] ?? null)) {
+                app(ResponseCache::class)->forgetGeneratedTranslations();
+            }
+
+            $kept['translation_language'] = is_string($language) && $language !== '' ? $language : null;
+        }
+
+        if (is_bool($settings['automatic_translation'] ?? null)) {
+            $kept['automatic_translation'] = $settings['automatic_translation'];
+        }
+
+        if (is_array($settings['translation_languages'] ?? null)) {
+            $kept['translation_languages'] = array_values(array_filter($settings['translation_languages'], fn (mixed $language): bool => is_array($language)
+                && is_string($language['code'] ?? null) && $language['code'] !== ''
+                && is_string($language['name'] ?? null) && is_string($language['native_name'] ?? null)));
+        }
+
+        Cache::forever(self::TranslationKey, $kept);
+    }
+
     /**
      * The version of the terms devnull last said you have yet to accept, so the app opens on them (see AcceptTerms),
      * or null when you're up to date.
@@ -234,5 +296,6 @@ public function forget(): void
         Cache::forget(self::PinWarningKey);
         Cache::forget(self::TimezoneKey);
         Cache::forget(self::TermsKey);
+        Cache::forget(self::TranslationKey);
     }
 }
diff --git a/app/Devnull/Client.php b/app/Devnull/Client.php
index b6538ae..8c92b79 100644
--- a/app/Devnull/Client.php
+++ b/app/Devnull/Client.php
@@ -123,6 +123,10 @@
 
     public const string SettingsPath = 'me/settings';
 
+    public const string TranslationLanguagePath = 'me/translation-language';
+
+    public const string AutomaticTranslationPath = 'me/automatic-translation';
+
     /**
      * This phone's push token, which devnull keeps on the device the request is signed with, and which push
      * notifications you get.
@@ -144,9 +148,13 @@
 
     public function __construct(private DeviceKey $deviceKey, private string $baseUrl, private ResponseCache $cache) {}
 
-    /**
-     * Where a vote on a commit's poll goes. devnull answers with the commit, whose poll then shows its results.
-     */
+    /** Cache-only GET and explicit generation POST share this per-commit endpoint. */
+    public static function translationPath(string $id): string
+    {
+        return 'commits/'.rawurlencode($id).'/translation';
+    }
+
+    /** Where a vote goes; devnull answers with the commit and its updated poll. */
     public static function pollVotesPath(string $id): string
     {
         return 'commits/'.rawurlencode($id).'/poll/votes';
@@ -892,9 +900,9 @@ private function signedMultipart(string $target, string $payload, array $files):
      *
      * @throws ConnectionException
      */
-    public static function sendSigned(SignedRequest $request): Response
+    public static function sendSigned(SignedRequest $request, int $timeout = 20): Response
     {
-        $pending = Http::acceptJson()->withHeaders($request->headers)->timeout(20);
+        $pending = Http::acceptJson()->withHeaders($request->headers)->timeout($timeout);
 
         $pending = $request->body === ''
             ? $pending->withRequestMiddleware(fn (RequestInterface $request): RequestInterface => $request->withoutHeader('Content-Type'))
@@ -1016,12 +1024,15 @@ private static function body(?array $payload): string
     }
 
     /**
-     * @return array{X-Devnull-Timestamp: string, X-Devnull-Nonce: string, X-SSH-Signature: string}
+     * @return array{X-Devnull-Timestamp: string, X-Devnull-Nonce: string, X-SSH-Signature: string, Accept-Language: string}
      */
     private function sign(string $method, string $target, string $body, string $namespace = RequestSigner::Namespace): array
     {
-        return (new RequestSigner($this->deviceKey->current()))
-            ->headers($method, $target, $body, CarbonImmutable::now()->getTimestamp(), RequestSigner::nonce(), $namespace);
+        return [
+            ...(new RequestSigner($this->deviceKey->current()))
+                ->headers($method, $target, $body, CarbonImmutable::now()->getTimestamp(), RequestSigner::nonce(), $namespace),
+            'Accept-Language' => app(TranslationLanguage::class)->yours(),
+        ];
     }
 
     /**
diff --git a/app/Devnull/Data/Commit.php b/app/Devnull/Data/Commit.php
index 6d19fdd..1c5defa 100644
--- a/app/Devnull/Data/Commit.php
+++ b/app/Devnull/Data/Commit.php
@@ -82,6 +82,7 @@ public function __construct(
         public ?ReplyPreview $replyPreview = null,
         public int $pasteisCount = 0,
         public ?ScoreCard $scoreCard = null,
+        public ?CommitTranslation $translation = null,
     ) {}
 
     /**
@@ -149,6 +150,7 @@ public static function fromArray(array $data): self
             replyPreview: is_array($data['reply_preview'] ?? null) ? ReplyPreview::fromArray($data['reply_preview']) : null,
             pasteisCount: max(0, (int) ($data['pasteis_count'] ?? 0)),
             scoreCard: $scoreCard,
+            translation: is_array($data['translation'] ?? null) ? CommitTranslation::fromArray($data['translation']) : null,
         );
     }
 
@@ -170,6 +172,29 @@ public function withMorePasteis(int $change): self
         return new self(...[...get_object_vars($this), 'pasteisCount' => max(0, $this->pasteisCount + $change)]);
     }
 
+    /** Whether this reader may request or display this commit's optional translation. */
+    public function canTranslateBy(?User $viewer): bool
+    {
+        return $viewer !== null && $this->isApproved() && ! $this->isDeleted()
+            && $this->author->id !== $viewer->id && $this->translation?->available === true;
+    }
+
+    /** A display-only copy; body and original excerpts are left on the source commit. */
+    public function displayingTranslation(): self
+    {
+        return $this->translation?->content === null ? $this : new self(...[
+            ...get_object_vars($this),
+            'content' => $this->translation->content,
+            'previewContent' => $this->translation->previewContent,
+        ]);
+    }
+
+    /** Replaces cached translation metadata without changing the original body. */
+    public function withTranslation(?CommitTranslation $translation): self
+    {
+        return new self(...[...get_object_vars($this), 'translation' => $translation]);
+    }
+
     public function withPinned(bool $isPinned): self
     {
         return new self(...[...get_object_vars($this), 'isPinned' => $isPinned]);
diff --git a/app/Devnull/Data/CommitTranslation.php b/app/Devnull/Data/CommitTranslation.php
new file mode 100644
index 0000000..2d798fb
--- /dev/null
+++ b/app/Devnull/Data/CommitTranslation.php
@@ -0,0 +1,100 @@
+<?php
+
+namespace App\Devnull\Data;
+
+/** The optional, cache-only translation attached to a signed commit. */
+final readonly class CommitTranslation
+{
+    /**
+     * @param  list<BodyBlock>|null  $content
+     * @param  list<BodyBlock>|null  $previewContent
+     */
+    public function __construct(
+        public string $language,
+        public ?string $sourceLanguage,
+        public ?string $sourceName,
+        public bool $available,
+        public ?array $content = null,
+        public ?array $previewContent = null,
+    ) {}
+
+    /** Whether preferences and a per-post override select this language's cached content. */
+    public function isDisplayed(string $language, bool $automatic, ?string $display = null): bool
+    {
+        return $this->language === $language && $this->content !== null
+            && ($display ?? ($automatic ? 'translated' : 'original')) === 'translated';
+    }
+
+    /**
+     * Reads optional metadata without ever assigning translated segments to the original commit body.
+     *
+     * @param  array<string, mixed>  $data
+     */
+    public static function fromArray(array $data): ?self
+    {
+        if (! is_string($data['language'] ?? null) || $data['language'] === '') {
+            return null;
+        }
+
+        $translated = is_array($data['translated'] ?? null) ? $data['translated'] : [];
+        $segments = self::segments($translated['body_segments'] ?? null);
+        $preview = self::segments($translated['preview_segments'] ?? null);
+        $body = $segments === null ? '' : self::body($segments);
+
+        return new self(
+            language: $data['language'],
+            sourceLanguage: is_string($data['source_language'] ?? null) ? $data['source_language'] : null,
+            sourceName: is_string($data['source_name'] ?? null) ? $data['source_name'] : null,
+            available: ($data['available'] ?? false) === true,
+            content: $segments === null ? null : CommitBody::blocks($body, $segments),
+            previewContent: $preview === null ? null : CommitBody::blocks(self::body($preview), $preview),
+        );
+    }
+
+    /**
+     * Rebuild fences from the highlighter's escaped code, never rendering its HTML.
+     * Mention offsets from the original are deliberately not reused.
+     *
+     * @param  list<array<string, mixed>>  $segments
+     */
+    private static function body(array $segments): string
+    {
+        $body = '';
+
+        foreach ($segments as $segment) {
+            $body .= match ($segment['type'] ?? null) {
+                'text' => is_string($segment['text'] ?? null) ? $segment['text'] : '',
+                'code' => '`'.(is_string($segment['code'] ?? null) ? $segment['code'] : '').'`',
+                'block' => self::fencedCode($segment),
+                default => '',
+            };
+        }
+
+        return $body;
+    }
+
+    /**
+     * Decodes escaped highlighter text and chooses a fence longer than any literal code backticks.
+     *
+     * @param  array<string, mixed>  $segment
+     */
+    private static function fencedCode(array $segment): string
+    {
+        $code = html_entity_decode(strip_tags(is_string($segment['html'] ?? null) ? $segment['html'] : ''), ENT_QUOTES | ENT_HTML5, 'UTF-8');
+        preg_match_all('/`+/', $code, $matches);
+        $length = max([2, ...array_map(strlen(...), $matches[0])]) + 1;
+        $fence = str_repeat('`', $length);
+
+        return "\n{$fence}\n{$code}\n{$fence}\n";
+    }
+
+    /**
+     * Missing segment arrays mean no cached translation, not an empty translated body.
+     *
+     * @return list<array<string, mixed>>|null
+     */
+    private static function segments(mixed $segments): ?array
+    {
+        return is_array($segments) ? array_values(array_filter($segments, is_array(...))) : null;
+    }
+}
diff --git a/app/Devnull/FetchInBackground.php b/app/Devnull/FetchInBackground.php
index bbb087c..c1e8159 100644
--- a/app/Devnull/FetchInBackground.php
+++ b/app/Devnull/FetchInBackground.php
@@ -67,14 +67,14 @@ public static function jsonOf(mixed $result): array
      * @param  array<string, string>  $headers
      * @return array{status: int, json: mixed, retry_after: string, from_devnull: bool}
      */
-    public function handle(string $url, array $headers, string $method = 'GET', string $body = '', bool $withImages = false, ?int $pruneBefore = null, string $contentType = 'application/json'): array
+    public function handle(string $url, array $headers, string $method = 'GET', string $body = '', bool $withImages = false, ?int $pruneBefore = null, string $contentType = 'application/json', int $requestTimeout = 20): array
     {
         if ($pruneBefore !== null) {
             DownloadImages::prune($pruneBefore);
         }
 
         try {
-            $response = Client::sendSigned(new SignedRequest($url, $headers, $method, $body, $contentType));
+            $response = Client::sendSigned(new SignedRequest($url, $headers, $method, $body, $contentType), $requestTimeout);
         } catch (ConnectionException) {
             return ['status' => 0, 'json' => null, 'retry_after' => '', 'from_devnull' => false];
         }
diff --git a/app/Devnull/ResponseCache.php b/app/Devnull/ResponseCache.php
index fadaa8a..a5d4745 100644
--- a/app/Devnull/ResponseCache.php
+++ b/app/Devnull/ResponseCache.php
@@ -240,6 +240,88 @@ public function flush(): void
         $this->store()->flush();
     }
 
+    /** Clears successful-generation protection when the account or target preference changes. */
+    public function forgetGeneratedTranslations(): void
+    {
+        $this->store()->forget('generated-translations');
+    }
+
+    /**
+     * Keeps explicit successes only, so older enclosing GETs cannot undo a write.
+     * The timestamp limits protection to requests already in flight, not future server decisions.
+     *
+     * @param  array<string, mixed>  $translation
+     */
+    public function rememberGeneratedTranslation(string $id, string $body, array $translation): void
+    {
+        $kept = $this->generatedTranslations();
+        $kept['commits'][$id] = ['body' => hash('sha256', $body), 'translation' => $translation, 'at' => microtime(true)];
+        $kept['commits'] = array_slice($kept['commits'], -self::MaxEntries, null, true);
+        $this->store()->put('generated-translations', $kept, now()->addDays(self::ShownForDays));
+    }
+
+    /**
+     * Restores successful translations throughout an older resource before both cache storage and DTO parsing.
+     * A body edit invalidates its overlay; account and target-language context never cross readers.
+     *
+     * @param  array<string, mixed>  $json
+     * @return array<string, mixed>
+     */
+    public function preserveGeneratedTranslations(array $json, float $requestedAt): array
+    {
+        $kept = $this->generatedTranslations();
+        if ($kept['commits'] === []) {
+            return $json;
+        }
+
+        $visit = function (array $node) use (&$visit, &$kept, $requestedAt): array {
+            $id = is_scalar($node['id'] ?? null) ? (string) $node['id'] : '';
+            $generated = $kept['commits'][$id] ?? null;
+
+            if ($generated !== null && is_string($node['body'] ?? null)) {
+                if ($generated['body'] !== hash('sha256', $node['body'])) {
+                    unset($kept['commits'][$id]);
+                } elseif ($generated['at'] > $requestedAt && ! isset($node['deleted_at'])
+                    && ($node['status'] ?? 'approved') === 'approved'
+                    && isset($node['author']) && ($node['author']['id'] ?? null) !== $kept['account']) {
+                    $node['translation'] = $generated['translation'];
+                }
+            }
+
+            foreach ($node as $key => $value) {
+                if (is_array($value)) {
+                    $node[$key] = $visit($value);
+                }
+            }
+
+            return $node;
+        };
+        $json = $visit($json);
+        $this->store()->put('generated-translations', $kept, now()->addDays(self::ShownForDays));
+
+        return $json;
+    }
+
+    /**
+     * One account and resolved target language own the protection, including the phone-language fallback.
+     *
+     * @return array{account: ?string, language: string, commits: array<string, array{body: string, translation: array<string, mixed>, at: float}>}
+     */
+    private function generatedTranslations(): array
+    {
+        $account = $this->userId();
+        $language = app(TranslationLanguage::class)->yours();
+        $kept = $this->store()->get('generated-translations');
+
+        if (is_array($kept) && $kept['account'] === $account && $kept['language'] === $language) {
+            return $kept;
+        }
+
+        $this->forgetGeneratedTranslations();
+
+        return ['account' => $account, 'language' => $language, 'commits' => []];
+    }
+
     // ── The app's own writes ──────────────────────
 
     /**
diff --git a/app/Devnull/RowInputs.php b/app/Devnull/RowInputs.php
index 0659a30..ac8ad7b 100644
--- a/app/Devnull/RowInputs.php
+++ b/app/Devnull/RowInputs.php
@@ -28,6 +28,7 @@ public static function for(Commit $commit, array $scope): array
 
         return [
             'viewer' => $viewer?->id,
+            'translation' => [app(TranslationLanguage::class)->yours(), app(Account::class)->automaticTranslation(), $scope['translationDisplay'] ?? [], $scope['translating'] ?? []],
             'pasteis' => $scope['pasteis'] ?? app(Account::class)->pasteis(),
             'stashed' => $scope['stashed'] ?? [],
             'unfolded' => $scope['unfolded'] ?? [],
diff --git a/app/Devnull/TranslationLanguage.php b/app/Devnull/TranslationLanguage.php
new file mode 100644
index 0000000..718497c
--- /dev/null
+++ b/app/Devnull/TranslationLanguage.php
@@ -0,0 +1,38 @@
+<?php
+
+namespace App\Devnull;
+
+use Carbon\CarbonImmutable;
+use Native\Mobile\Facades\Device;
+
+/** The saved language, or the phone's primary language, with English as the fallback. */
+final class TranslationLanguage
+{
+    /** @var array{language: string, at: int}|null */
+    private ?array $phone = null;
+
+    /** Chooses a supported account or phone language without requesting settings per row. */
+    public function yours(): string
+    {
+        $account = app(Account::class);
+        $language = $account->translationLanguage() ?? $this->phone();
+        $known = array_column($account->translationLanguages(), 'code');
+
+        return $known === [] || in_array($language, $known, true) ? $language : 'en';
+    }
+
+    /** Keeps native device info for a minute and extracts its BCP47 primary language. */
+    private function phone(): string
+    {
+        $now = CarbonImmutable::now()->getTimestamp();
+
+        if ($this->phone === null || $now - $this->phone['at'] >= 60) {
+            $info = json_decode((string) Device::getInfo(), true);
+            $locale = is_array($info) ? ($info['language'] ?? null) : null;
+            $language = is_string($locale) && preg_match('/^([a-z]{2,3})(?:[-_]|$)/i', $locale, $matches) === 1 ? strtolower($matches[1]) : 'en';
+            $this->phone = ['language' => $language, 'at' => $now];
+        }
+
+        return $this->phone['language'];
+    }
+}
diff --git a/app/NativeComponents/Concerns/ManagesTranslationSettings.php b/app/NativeComponents/Concerns/ManagesTranslationSettings.php
new file mode 100644
index 0000000..9199ef1
--- /dev/null
+++ b/app/NativeComponents/Concerns/ManagesTranslationSettings.php
@@ -0,0 +1,193 @@
+<?php
+
+namespace App\NativeComponents\Concerns;
+
+use App\Devnull\Account;
+use App\Devnull\Client;
+
+trait ManagesTranslationSettings
+{
+    public ?string $chosenTranslationLanguage = null;
+
+    public ?string $savedTranslationLanguage = null;
+
+    public bool $automaticTranslation = true;
+
+    public bool $pickingTranslationLanguage = false;
+
+    public bool $listingTranslationLanguages = false;
+
+    public string $translationLanguageQuery = '';
+
+    public bool $savingTranslationLanguage = false;
+
+    public bool $savingAutomaticTranslation = false;
+
+    public ?string $translationSettingsError = null;
+
+    /** Invalidates writes whose scoped callbacks were dropped while Account was covered. */
+    protected int $translationSettingsRevision = 0;
+
+    /** Restores pending controls on resume; fresh settings reconcile writes that succeeded off-screen. */
+    protected function recoverTranslationSettings(): void
+    {
+        $this->translationSettingsRevision++;
+
+        if ($this->savingTranslationLanguage) {
+            $this->chosenTranslationLanguage = $this->savedTranslationLanguage;
+        }
+
+        $this->savingTranslationLanguage = false;
+        $this->savingAutomaticTranslation = false;
+        $this->automaticTranslation = app(Account::class)->automaticTranslation();
+    }
+
+    /** Seeds settings from this account while a quiet settings refresh is in flight. */
+    protected function loadTranslationSettings(): void
+    {
+        $account = app(Account::class);
+        $this->savedTranslationLanguage = $this->chosenTranslationLanguage = $account->translationLanguage();
+        $this->automaticTranslation = $account->automaticTranslation();
+    }
+
+    /**
+     * Takes only fields present in a partial settings answer, retaining an unsaved language selection.
+     *
+     * @param  array<string, mixed>  $settings
+     */
+    protected function takeTranslationSettings(array $settings): void
+    {
+        $account = app(Account::class);
+        $unchanged = $this->chosenTranslationLanguage === $this->savedTranslationLanguage;
+        $account->rememberTranslationSettings($settings);
+        $this->savedTranslationLanguage = $account->translationLanguage();
+
+        if ($unchanged) {
+            $this->chosenTranslationLanguage = $this->savedTranslationLanguage;
+        }
+
+        if (! $this->savingAutomaticTranslation) {
+            $this->automaticTranslation = $account->automaticTranslation();
+        }
+    }
+
+    /** @return list<array{code: string, name: string, native_name: string}> */
+    public function translationLanguages(): array
+    {
+        return array_slice($this->matchingTranslationLanguages(), 0, 50);
+    }
+
+    /** The matches omitted to keep a large supported-language corpus within EDGE's frame budget. */
+    public function translationLanguagesMore(): int
+    {
+        return max(0, count($this->matchingTranslationLanguages()) - 50);
+    }
+
+    /** @return list<array{code: string, name: string, native_name: string}> */
+    private function matchingTranslationLanguages(): array
+    {
+        $query = mb_strtolower(trim($this->translationLanguageQuery));
+
+        return array_values(array_filter(app(Account::class)->translationLanguages(), fn (array $language): bool => $query === ''
+            || str_contains(mb_strtolower(implode(' ', $language)), $query)));
+    }
+
+    /** Human-readable selection using both English and native names. */
+    public function translationLanguageName(): string
+    {
+        foreach (app(Account::class)->translationLanguages() as $language) {
+            if ($language['code'] === $this->chosenTranslationLanguage) {
+                return $language['name'].' · '.$language['native_name'];
+            }
+        }
+
+        return $this->chosenTranslationLanguage ?? 'Use phone language';
+    }
+
+    /** Opens a fresh searchable picker; rows remain mounted until native dismissal completes. */
+    public function pickTranslationLanguage(): void
+    {
+        $this->translationLanguageQuery = '';
+        $this->listingTranslationLanguages = true;
+        $this->pickingTranslationLanguage = true;
+    }
+
+    /** Selects a supported language, or the phone default, without saving until explicitly requested. */
+    public function chooseTranslationLanguage(?string $language): void
+    {
+        if ($language !== null && ! in_array($language, array_column(app(Account::class)->translationLanguages(), 'code'), true)) {
+            return;
+        }
+
+        $this->chosenTranslationLanguage = $language;
+        $this->pickingTranslationLanguage = false;
+        $this->translationSettingsError = null;
+    }
+
+    /** Releases the picker list after the native sheet has finished dismissing. */
+    public function translationLanguageSheetClosed(): void
+    {
+        $this->pickingTranslationLanguage = false;
+        $this->listingTranslationLanguages = false;
+    }
+
+    /** Persists the submitted language because the write response contains me, not settings. */
+    public function saveTranslationLanguage(): void
+    {
+        if ($this->savingTranslationLanguage || app(Account::class)->translationLanguages() === [] || $this->current === null || $this->chosenTranslationLanguage === $this->savedTranslationLanguage) {
+            return;
+        }
+
+        $revision = $this->translationSettingsRevision;
+        $language = $this->chosenTranslationLanguage;
+        $this->savingTranslationLanguage = true;
+        $this->translationSettingsError = null;
+        $this->writeInBackground('PUT', Client::TranslationLanguagePath, ['translation_language' => $language], function (array $json) use ($language, $revision): void {
+            if ($revision !== $this->translationSettingsRevision) {
+                return;
+            }
+
+            $this->savingTranslationLanguage = false;
+            $this->takeMe($json);
+            app(Account::class)->rememberTranslationSettings(['translation_language' => $language]);
+            $this->savedTranslationLanguage = $language;
+        }, function (string $message) use ($revision): void {
+            if ($revision !== $this->translationSettingsRevision) {
+                return;
+            }
+
+            $this->savingTranslationLanguage = false;
+            $this->translationSettingsError = $message;
+        });
+    }
+
+    /** Saves an explicit switch change and restores the last saved value if devnull refuses it. */
+    public function setAutomaticTranslation(bool $enabled): void
+    {
+        if ($this->savingAutomaticTranslation || app(Account::class)->translationLanguages() === [] || $this->current === null) {
+            return;
+        }
+
+        $revision = $this->translationSettingsRevision;
+        $this->automaticTranslation = $enabled;
+        $this->savingAutomaticTranslation = true;
+        $this->translationSettingsError = null;
+        $this->writeInBackground('PUT', Client::AutomaticTranslationPath, ['enabled' => $enabled], function (array $json) use ($enabled, $revision): void {
+            if ($revision !== $this->translationSettingsRevision) {
+                return;
+            }
+
+            $this->savingAutomaticTranslation = false;
+            $this->takeMe($json);
+            app(Account::class)->rememberTranslationSettings(['automatic_translation' => $enabled]);
+        }, function (string $message) use ($revision): void {
+            if ($revision !== $this->translationSettingsRevision) {
+                return;
+            }
+
+            $this->savingAutomaticTranslation = false;
+            $this->automaticTranslation = app(Account::class)->automaticTranslation();
+            $this->translationSettingsError = $message;
+        });
+    }
+}
diff --git a/app/NativeComponents/Concerns/RefreshesInBackground.php b/app/NativeComponents/Concerns/RefreshesInBackground.php
index 600f5c3..79f9526 100644
--- a/app/NativeComponents/Concerns/RefreshesInBackground.php
+++ b/app/NativeComponents/Concerns/RefreshesInBackground.php
@@ -111,11 +111,11 @@ protected function refresh(string $path, array $query, Closure $apply, bool $aga
             return;
         }
 
-        $this->refreshing[$key] = microtime(true);
+        $requestedAt = $this->refreshing[$key] = microtime(true);
 
         FetchInBackground::dispatch($request->url, $request->headers, 'GET', '', $withImages, $withImages ? ImageCache::takePrune() : null)
             ->timeout(30)
-            ->finished(function (mixed $result) use ($key, $path, $query, $apply, $quiet, $failed, $withImages, $retried): void {
+            ->finished(function (mixed $result) use ($key, $path, $query, $apply, $quiet, $failed, $withImages, $retried, $requestedAt): void {
                 unset($this->refreshing[$key]);
 
                 $result = is_array($result) ? $result : [];
@@ -126,7 +126,7 @@ protected function refresh(string $path, array $query, Closure $apply, bool $aga
                     return;
                 }
 
-                $this->settleRefresh($result, $path, $query, $apply, $quiet, $failed, $withImages);
+                $this->settleRefresh($result, $path, $query, $apply, $quiet, $failed, $withImages, $requestedAt);
             })
             ->failed(function (Throwable $exception) use ($key, $quiet, $failed): void {
                 unset($this->refreshing[$key]);
@@ -190,6 +190,7 @@ protected function refreshSettings(): void
         $this->refresh(Client::SettingsPath, [], function (array $json): void {
             $settings = is_array($json['data'] ?? null) ? $json['data'] : [];
             $timezone = $settings['timezone'] ?? null;
+            app(Account::class)->rememberTranslationSettings($settings);
 
             app(Account::class)->rememberTimezone(Timezone::isKnown($timezone) ? $timezone : null);
         }, quiet: true);
@@ -212,6 +213,10 @@ protected function refused(ApiException $exception): bool
     protected function forgetRefreshes(): void
     {
         $this->refreshing = [];
+
+        if (method_exists($this, 'forgetTranslationRequests')) {
+            $this->forgetTranslationRequests();
+        }
     }
 
     /**
@@ -220,13 +225,14 @@ protected function forgetRefreshes(): void
      * @param  Closure(array<string, mixed>): void  $apply
      * @param  (Closure(): void)|null  $failed
      */
-    private function settleRefresh(array $result, string $path, array $query, Closure $apply, bool $quiet, ?Closure $failed = null, bool $withImages = false): void
+    private function settleRefresh(array $result, string $path, array $query, Closure $apply, bool $quiet, ?Closure $failed = null, bool $withImages = false, float $requestedAt = 0): void
     {
         $status = (int) ($result['status'] ?? 0);
         $successful = $status >= 200 && $status < 300;
 
         if ($successful && ($result['from_devnull'] ?? false) === true) {
             $json = is_array($result['json'] ?? null) ? $result['json'] : [];
+            $json = app(ResponseCache::class)->preserveGeneratedTranslations($json, $requestedAt);
 
             app(ResponseCache::class)->put($path, $query, $json);
 
@@ -242,6 +248,10 @@ private function settleRefresh(array $result, string $path, array $query, Closur
 
             $apply($json);
 
+            if (method_exists($this, 'refreshShownTranslations')) {
+                $this->refreshShownTranslations();
+            }
+
             return;
         }
 
diff --git a/app/NativeComponents/Concerns/ShowsCommits.php b/app/NativeComponents/Concerns/ShowsCommits.php
index da0f7fe..5cc0cff 100644
--- a/app/NativeComponents/Concerns/ShowsCommits.php
+++ b/app/NativeComponents/Concerns/ShowsCommits.php
@@ -44,6 +44,7 @@ trait ShowsCommits
 {
     use OpensCommitSheet;
     use OpensStargazers;
+    use TranslatesCommits;
     use VotesOnPolls;
     use WritesInBackground;
 
@@ -371,7 +372,8 @@ public function closeImageViewer(): void
      */
     public function openLink(string $id, int $index): void
     {
-        $link = $this->shownCommit($id)?->links()[$index] ?? null;
+        $commit = $this->shownCommit($id);
+        $link = $commit === null ? null : ($this->displayedCommit($commit)->links()[$index] ?? null);
 
         if ($link?->commit !== null) {
             $this->openCommit($link->commit);
@@ -563,9 +565,13 @@ protected function showStar(string $id, bool $starred, ?Commit $fresh = null): v
      */
     private function changeShownCommit(string $id, Closure $change): void
     {
-        $changeCopy = fn (Commit $commit): Commit => $commit->id === $id ? $change($commit) : $commit;
+        $changeCopy = function (Commit $commit) use (&$changeCopy, $id, $change): Commit {
+            $commit = $commit->id === $id ? $change($commit) : $commit;
+
+            return $commit->withPreviewReplies($changeCopy)->withQuotedCommit($changeCopy);
+        };
 
-        $this->updateShownCommits(fn (Commit $commit): Commit => $changeCopy($commit)->withPreviewReplies($changeCopy)->withQuotedCommit($changeCopy));
+        $this->updateShownCommits($changeCopy);
     }
 
     /**
@@ -575,14 +581,20 @@ private function changeShownCommit(string $id, Closure $change): void
      */
     private function everyShownCommit(): iterable
     {
-        foreach ($this->shownCommits() as $commit) {
+        $nested = function (Commit $commit) use (&$nested): iterable {
             yield $commit;
 
             if ($commit->quotedCommit !== null) {
-                yield $commit->quotedCommit;
+                yield from $nested($commit->quotedCommit);
             }
 
-            yield from $commit->replyPreview?->replies ?? [];
+            foreach ($commit->replyPreview?->replies ?? [] as $reply) {
+                yield from $nested($reply);
+            }
+        };
+
+        foreach ($this->shownCommits() as $commit) {
+            yield from $nested($commit);
         }
     }
 
diff --git a/app/NativeComponents/Concerns/TranslatesCommits.php b/app/NativeComponents/Concerns/TranslatesCommits.php
new file mode 100644
index 0000000..8c92e8b
--- /dev/null
+++ b/app/NativeComponents/Concerns/TranslatesCommits.php
@@ -0,0 +1,178 @@
+<?php
+
+namespace App\NativeComponents\Concerns;
+
+use App\Devnull\Account;
+use App\Devnull\Client;
+use App\Devnull\Data\Commit;
+use App\Devnull\Data\CommitTranslation;
+use App\Devnull\ResponseCache;
+use App\Devnull\SignedRequest;
+use App\Devnull\Toasts;
+use App\Devnull\TranslationLanguage;
+
+trait TranslatesCommits
+{
+    /** @var array<string, string> */
+    public array $translationDisplay = [];
+
+    /** @var array<string, string> */
+    public array $translating = [];
+
+    /** @var array<string, string> */
+    protected array $readingTranslations = [];
+
+    /** @var array<string, float> */
+    protected array $translationsReadAt = [];
+
+    /** Keeps the original selected even when a refresh discovers a cached translation. */
+    public function showOriginal(string $id): void
+    {
+        $this->translationDisplay[$id] = 'original';
+    }
+
+    /** Mirrors the card's eligibility checks for calls dispatched from native callbacks. */
+    public function canTranslate(Commit $commit): bool
+    {
+        return $commit->canTranslateBy(app(Account::class)->user());
+    }
+
+    /** Whether this card currently displays the cached translation rather than its original. */
+    public function isTranslated(Commit $commit): bool
+    {
+        return $this->canTranslate($commit) && $commit->translation->isDisplayed(
+            app(TranslationLanguage::class)->yours(), app(Account::class)->automaticTranslation(), $this->translationDisplay[$commit->id] ?? null,
+        );
+    }
+
+    /** A display copy only: the original body, excerpts and action payloads never change. */
+    public function displayedCommit(Commit $commit): Commit
+    {
+        return $this->isTranslated($commit) ? $commit->displayingTranslation() : $commit;
+    }
+
+    /** Generates only after an explicit tap, or reveals content already cached in this language. */
+    public function translateCommit(string $id): void
+    {
+        $commit = $this->shownCommit($id);
+
+        if ($commit === null || ! $this->canTranslate($commit) || isset($this->translating[$id])) {
+            return;
+        }
+
+        $language = app(TranslationLanguage::class)->yours();
+        $this->translationDisplay[$id] = 'translated';
+
+        if ($commit->translation?->language === $language && $commit->translation->content !== null) {
+            return;
+        }
+
+        $token = bin2hex(random_bytes(8));
+        $this->translating[$id] = $token;
+        $body = $commit->body;
+        $accountId = app(Account::class)->user()?->id;
+
+        $key = $this->translationRequestKey($id, $body, $language);
+        $this->sendInBackground(fn (Client $client): SignedRequest => $client->signedWrite('POST', Client::translationPath($id), ['language' => $language]), function (array $json) use ($id, $body, $language, $token, $key, $accountId): void {
+            if (($this->translating[$id] ?? null) !== $token) {
+                return;
+            }
+
+            unset($this->translating[$id]);
+            $this->translationRevisions[$key] = ($this->translationRevisions[$key] ?? 0) + 1;
+            $this->takeTranslation($id, $body, $language, $json, $accountId, generated: true);
+        }, function (string $message) use ($id, $token): void {
+            if (($this->translating[$id] ?? null) !== $token) {
+                return;
+            }
+
+            unset($this->translating[$id]);
+            Toasts::failed($message);
+        }, timeout: 90, requestTimeout: 80);
+    }
+
+    /** @var array<string, int> Successful explicit generations supersede older cache reads. */
+    protected array $translationRevisions = [];
+
+    /** Reads shared cache only. Scrolling or refreshing must never generate a translation. */
+    protected function refreshShownTranslations(): void
+    {
+        $language = app(TranslationLanguage::class)->yours();
+
+        foreach ($this->everyShownCommit() as $commit) {
+            if (! $this->canTranslate($commit) || ($commit->translation?->language === $language && $commit->translation->content !== null)) {
+                continue;
+            }
+
+            $key = $this->translationRequestKey($commit->id, $commit->body, $language);
+
+            if (isset($this->readingTranslations[$key]) || microtime(true) - ($this->translationsReadAt[$key] ?? 0) < 30) {
+                continue;
+            }
+
+            $revision = $this->translationRevisions[$key] ?? 0;
+            $token = bin2hex(random_bytes(8));
+            $this->readingTranslations[$key] = $token;
+            $id = $commit->id;
+            $body = $commit->body;
+            $accountId = app(Account::class)->user()?->id;
+            $this->sendInBackground(fn (Client $client): SignedRequest => $client->signedGet(Client::translationPath($id), ['language' => $language]), function (array $json) use ($id, $body, $language, $key, $token, $revision, $accountId): void {
+                if (($this->readingTranslations[$key] ?? null) !== $token) {
+                    return;
+                }
+
+                unset($this->readingTranslations[$key]);
+                $this->translationsReadAt[$key] = microtime(true);
+                if (($this->translationRevisions[$key] ?? 0) === $revision) {
+                    $this->takeTranslation($id, $body, $language, $json, $accountId);
+                }
+            }, function () use ($key, $token): void {
+                if (($this->readingTranslations[$key] ?? null) === $token) {
+                    unset($this->readingTranslations[$key]);
+                }
+            });
+        }
+    }
+
+    /** Drops callbacks NativePHP discarded under another screen, allowing resume to request again. */
+    protected function forgetTranslationRequests(): void
+    {
+        $this->translating = [];
+        $this->readingTranslations = [];
+        $this->translationsReadAt = [];
+        $this->translationRevisions = [];
+        $this->refreshSettings();
+    }
+
+    /** Identifies a translation independently of stale body edits or a changed target language. */
+    private function translationRequestKey(string $id, string $body, string $language): string
+    {
+        return hash('sha256', $id."\0".$body."\0".$language);
+    }
+
+    /**
+     * Applies matching body/language results to shown and cached copies without altering display overrides.
+     *
+     * @param  array<string, mixed>  $json
+     */
+    private function takeTranslation(string $id, string $body, string $language, array $json, ?string $accountId, bool $generated = false): void
+    {
+        if ($accountId !== app(Account::class)->user()?->id || $language !== app(TranslationLanguage::class)->yours() || ! array_key_exists('translation', $json)) {
+            return;
+        }
+
+        $data = is_array($json['translation']) ? $json['translation'] : null;
+        $translation = $data === null ? null : CommitTranslation::fromArray($data);
+
+        if ($translation !== null && $translation->language !== $language) {
+            return;
+        }
+
+        if ($generated && $translation?->content !== null && $this->shownCommit($id)?->body === $body) {
+            app(ResponseCache::class)->rememberGeneratedTranslation($id, $body, $data);
+        }
+
+        $this->changeShownCommit($id, fn (Commit $shown): Commit => $shown->body === $body ? $shown->withTranslation($translation) : $shown);
+        app(ResponseCache::class)->patchCommit($id, fn (array $kept): array => ($kept['body'] ?? null) === $body ? [...$kept, 'translation' => $data] : $kept);
+    }
+}
diff --git a/app/NativeComponents/Concerns/WritesInBackground.php b/app/NativeComponents/Concerns/WritesInBackground.php
index d7cb0b4..ec92a60 100644
--- a/app/NativeComponents/Concerns/WritesInBackground.php
+++ b/app/NativeComponents/Concerns/WritesInBackground.php
@@ -43,7 +43,7 @@ protected function writeInBackground(string $method, string $path, ?array $paylo
      * @param  Closure(array<string, mixed>): void  $done
      * @param  Closure(string, ?ApiException): void  $failed
      */
-    protected function sendInBackground(Closure $sign, Closure $done, Closure $failed, int $timeout = 30): void
+    protected function sendInBackground(Closure $sign, Closure $done, Closure $failed, int $timeout = 30, int $requestTimeout = 20): void
     {
         try {
             $request = $sign(app(Client::class));
@@ -53,7 +53,7 @@ protected function sendInBackground(Closure $sign, Closure $done, Closure $faile
             return;
         }
 
-        FetchInBackground::dispatch($request->url, $request->headers, $request->method, $request->body, false, null, $request->contentType)
+        FetchInBackground::dispatch($request->url, $request->headers, $request->method, $request->body, false, null, $request->contentType, $requestTimeout)
             ->timeout($timeout)
             ->finished(function (mixed $result) use ($done, $failed): void {
                 $exception = FetchInBackground::failureOf($result);
diff --git a/app/NativeComponents/ThisDevice.php b/app/NativeComponents/ThisDevice.php
index 25c2c46..72e80d7 100644
--- a/app/NativeComponents/ThisDevice.php
+++ b/app/NativeComponents/ThisDevice.php
@@ -17,6 +17,7 @@
 use App\Devnull\Timezone;
 use App\Devnull\WhoToFollow;
 use App\NativeComponents\Concerns\LeavesDevnull;
+use App\NativeComponents\Concerns\ManagesTranslationSettings;
 use App\NativeComponents\Concerns\OpensLegalPages;
 use App\NativeComponents\Concerns\RefreshesInBackground;
 use App\NativeComponents\Concerns\SendsPushToken;
@@ -56,6 +57,7 @@
 class ThisDevice extends NativeComponent
 {
     use LeavesDevnull;
+    use ManagesTranslationSettings;
     use OpensLegalPages;
     use RefreshesInBackground;
     use SendsPushToken;
@@ -219,6 +221,7 @@ public function mount(): void
         }
 
         $this->savedTimezone = $this->chosenTimezone = app(Account::class)->timezone();
+        $this->loadTranslationSettings();
 
         $this->pushPermission = PushNotifications::checkPermission();
         $this->pushOn = PushPrompt::allowed($this->pushPermission) && PushNotifications::getToken() !== null;
@@ -235,6 +238,14 @@ public function mount(): void
         $this->revalidate();
     }
 
+    /** Reconciles preference writes completed while native callbacks were scoped to another screen. */
+    public function onResume(): void
+    {
+        $this->forgetRefreshes();
+        $this->recoverTranslationSettings();
+        $this->revalidate();
+    }
+
     protected function revalidate(): void
     {
         $this->refresh('me', [], function (array $json): void {
@@ -741,6 +752,10 @@ public function render(): View
             'phoneTimezone' => app(Timezone::class)->phone(),
             'timezoneChanged' => $current !== null && $this->timezoneChanged(),
             'timezones' => $this->listingTimezones ? $this->timezones() : ['zones' => [], 'more' => 0],
+            'translationSettingsAvailable' => app(Account::class)->translationLanguages() !== [],
+            'translationLanguageName' => $this->translationLanguageName(),
+            'translationLanguages' => $this->listingTranslationLanguages ? $this->translationLanguages() : [],
+            'translationLanguagesMore' => $this->listingTranslationLanguages ? $this->translationLanguagesMore() : 0,
             'pasteisMode' => $current?->pasteisMode ?? false,
             'showsWhoToFollow' => app(WhoToFollow::class)->shows($this->me()?->id),
             'remotes' => $current?->remotes,
@@ -844,6 +859,7 @@ private function laneOptions(CurrentUser $current): array
      */
     private function takeSettings(array $settings): void
     {
+        $this->takeTranslationSettings($settings);
         $timezone = Timezone::isKnown($settings['timezone'] ?? null) ? $settings['timezone'] : null;
         $showsLocalTime = $timezone !== null && ($settings['show_local_time'] ?? false) === true;
 
diff --git a/app/Providers/AppServiceProvider.php b/app/Providers/AppServiceProvider.php
index 70c92b4..c496e8f 100644
--- a/app/Providers/AppServiceProvider.php
+++ b/app/Providers/AppServiceProvider.php
@@ -11,6 +11,7 @@
 use App\Devnull\ResponseCache;
 use App\Devnull\SignIn;
 use App\Devnull\Timezone;
+use App\Devnull\TranslationLanguage;
 use Carbon\CarbonImmutable;
 use Illuminate\Contracts\Foundation\Application;
 use Illuminate\Support\Facades\Date;
@@ -38,6 +39,7 @@ public function register(): void
         $this->app->singleton(AppleSignIn::class);
         $this->app->singleton(ImageCache::class);
         $this->app->singleton(Timezone::class);
+        $this->app->singleton(TranslationLanguage::class);
     }
 
     /**
diff --git a/composer.json b/composer.json
index bfde957..e827e17 100644
--- a/composer.json
+++ b/composer.json
@@ -33,7 +33,7 @@
         "laravel/boost": "^2.0",
         "laravel/framework": "^13.0",
         "laravel/tinker": "^3.0",
-        "nativephp/mobile": "^4.7",
+        "nativephp/mobile": "dev-main#10c21b24f120df706ed4584f451dd9077c297398 as 4.7.0",
         "nativephp/mobile-browser": "^1.2",
         "nativephp/mobile-camera": "^1.1",
         "nativephp/mobile-clipboard": "^1.0",
@@ -43,7 +43,7 @@
         "nativephp/mobile-secure-storage": "^1.1",
         "nativephp/mobile-share": "^1.1",
         "nativephp/mobile-skia": "^1.0",
-        "nativephp/mobile-ui": "^0.9",
+        "nativephp/mobile-ui": "dev-main#55f7c42c8e639a7a37bf862e91efe37d304120b6 as 0.9.0",
         "s2br/nativephp-mobile-splashscreen": "^1.4",
         "victorycodedev/toastkit": "dev-fix/android-toasts-above-sheets as 1.4.0"
     },
diff --git a/composer.lock b/composer.lock
index e9cd601..ca38390 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "745d59f03866816f94bab0b20f027a25",
+    "content-hash": "9a26745036a24e2016ce496cc8e891a4",
     "packages": [
         {
             "name": "bacon/bacon-qr-code",
@@ -2755,16 +2755,16 @@
         },
         {
             "name": "nativephp/mobile",
-            "version": "4.7.0",
+            "version": "dev-main",
             "source": {
                 "type": "git",
                 "url": "https://github.com/NativePHP/mobile-air.git",
-                "reference": "0d7e2e6509b1a0514726e67016fecade5e9137b2"
+                "reference": "10c21b24f120df706ed4584f451dd9077c297398"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/NativePHP/mobile-air/zipball/0d7e2e6509b1a0514726e67016fecade5e9137b2",
-                "reference": "0d7e2e6509b1a0514726e67016fecade5e9137b2",
+                "url": "https://api.github.com/repos/NativePHP/mobile-air/zipball/10c21b24f120df706ed4584f451dd9077c297398",
+                "reference": "10c21b24f120df706ed4584f451dd9077c297398",
                 "shasum": ""
             },
             "require": {
@@ -2804,6 +2804,7 @@
             "suggest": {
                 "ext-zip": "Required by native:install to validate and extract the downloaded Android PHP binary archives"
             },
+            "default-branch": true,
             "type": "library",
             "extra": {
                 "laravel": {
@@ -2846,9 +2847,9 @@
             ],
             "support": {
                 "issues": "https://github.com/NativePHP/mobile-air/issues",
-                "source": "https://github.com/NativePHP/mobile-air/tree/4.7.0"
+                "source": "https://github.com/NativePHP/mobile-air/tree/main"
             },
-            "time": "2026-10-29T17:31:02+00:00"
+            "time": "2026-11-05T15:42:02+00:00"
         },
         {
             "name": "nativephp/mobile-browser",
@@ -3355,16 +3356,16 @@
         },
         {
             "name": "nativephp/mobile-ui",
-            "version": "0.9.0",
+            "version": "dev-main",
             "source": {
                 "type": "git",
                 "url": "https://github.com/NativePHP/mobile-ui.git",
-                "reference": "9cee87cbc676a6500247bec99be5d19f633a04e9"
+                "reference": "55f7c42c8e639a7a37bf862e91efe37d304120b6"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/NativePHP/mobile-ui/zipball/9cee87cbc676a6500247bec99be5d19f633a04e9",
-                "reference": "9cee87cbc676a6500247bec99be5d19f633a04e9",
+                "url": "https://api.github.com/repos/NativePHP/mobile-ui/zipball/55f7c42c8e639a7a37bf862e91efe37d304120b6",
+                "reference": "55f7c42c8e639a7a37bf862e91efe37d304120b6",
                 "shasum": ""
             },
             "require": {
@@ -3376,6 +3377,7 @@
                 "orchestra/testbench": "^10.0",
                 "pestphp/pest": "^3.0"
             },
+            "default-branch": true,
             "type": "nativephp-plugin",
             "extra": {
                 "laravel": {
@@ -11562,6 +11564,18 @@
         }
     ],
     "aliases": [
+        {
+            "package": "nativephp/mobile",
+            "version": "dev-main",
+            "alias": "4.7.0",
+            "alias_normalized": "4.7.0.0"
+        },
+        {
+            "package": "nativephp/mobile-ui",
+            "version": "dev-main",
+            "alias": "0.9.0",
+            "alias_normalized": "0.9.0.0"
+        },
         {
             "package": "victorycodedev/toastkit",
             "version": "dev-fix/android-toasts-above-sheets",
@@ -11571,6 +11585,8 @@
     ],
     "minimum-stability": "stable",
     "stability-flags": {
+        "nativephp/mobile": 20,
+        "nativephp/mobile-ui": 20,
         "victorycodedev/toastkit": 20
     },
     "prefer-stable": true,
diff --git a/resources/views/native/partials/commit-body.blade.php b/resources/views/native/partials/commit-body.blade.php
index 349ac9e..0b1d0ab 100644
--- a/resources/views/native/partials/commit-body.blade.php
+++ b/resources/views/native/partials/commit-body.blade.php
@@ -25,11 +25,20 @@
     opens the rest where it is. The commit a page is about ($focused) is always whole. $muted sets it in muted ink, for
     the commits around the one a page is about.
 --}}
-@php($size ??= 'text-[15px]')
-@php($ink = ($muted ?? false) ? 'text-theme-ink-muted' : 'text-theme-ink')
-@php($folded = ! ($focused ?? false) && $commit->isFolded() && ! in_array($commit->id, $unfolded ?? [], true))
+@php
+    $size ??= 'text-[15px]';
+    $ink = ($muted ?? false) ? 'text-theme-ink-muted' : 'text-theme-ink';
+    $translationEligible = $commit instanceof \App\Devnull\Data\Commit && $commit->canTranslateBy($viewer ?? app(\App\Devnull\Account::class)->user());
+    $translated = $translationEligible && $commit->translation->isDisplayed(
+        app(\App\Devnull\TranslationLanguage::class)->yours(),
+        app(\App\Devnull\Account::class)->automaticTranslation(),
+        $translationDisplay[$commit->id] ?? null,
+    );
+    $displayCommit = $translated ? $commit->displayingTranslation() : $commit;
+@endphp
+@php($folded = ! ($focused ?? false) && $displayCommit->isFolded() && ! in_array($commit->id, $unfolded ?? [], true))
 @php($linkIndex = 0)
-@foreach ($folded ? $commit->previewContent : $commit->content as $block)
+@foreach ($folded ? $displayCommit->previewContent : $displayCommit->content as $block)
     @if ($block->isCode())
         <native:column class="w-full mt-1 mb-1 rounded-md border border-theme-hairline bg-theme-wash">
             @if ($block->language)
@@ -70,3 +79,5 @@
         <native:text font="medium" class="{{ $size }} text-theme-primary">Show more</native:text>
     </native:pressable>
 @endif
+
+@include('native.partials.commit-translation-controls')
diff --git a/resources/views/native/partials/commit-translation-controls.blade.php b/resources/views/native/partials/commit-translation-controls.blade.php
new file mode 100644
index 0000000..abb99e6
--- /dev/null
+++ b/resources/views/native/partials/commit-translation-controls.blade.php
@@ -0,0 +1,13 @@
+{{-- Shared translation notice/actions, separate from full or compact body rendering. --}}
+@if ($translationEligible)
+    <native:column class="w-full pt-2 gap-1">
+        @if ($translated)
+            <native:text ref="translation-source-{{ $commit->id }}" class="text-xs text-theme-ink-muted">Translated from {{ $commit->translation->sourceName ?? $commit->translation->sourceLanguage ?? 'another language' }}</native:text>
+            <native:pressable ref="show-original-{{ $commit->id }}" @press="showOriginal('{{ $commit->id }}')" a11y-label="Show original" class="min-h-[44] justify-center">
+                <native:text class="text-sm text-theme-primary">Show original</native:text>
+            </native:pressable>
+        @else
+            <native:button ref="translate-{{ $commit->id }}" variant="ghost" size="sm" :loading="isset($translating[$commit->id])" :disabled="isset($translating[$commit->id])" @press="translateCommit('{{ $commit->id }}')" a11y-label="Translate commit">{{ isset($translating[$commit->id]) ? 'Translating…' : 'Translate' }}</native:button>
+        @endif
+    </native:column>
+@endif
diff --git a/resources/views/native/partials/quoted-commit.blade.php b/resources/views/native/partials/quoted-commit.blade.php
index f919a70..e8d23c5 100644
--- a/resources/views/native/partials/quoted-commit.blade.php
+++ b/resources/views/native/partials/quoted-commit.blade.php
@@ -33,7 +33,10 @@
                     @include('native.partials.status-chip', ['status' => $quoted->status, 'small' => true])
                 @endunless
             </native:row>
-            <native:text class="w-full text-[15px] leading-relaxed text-theme-ink" :max-lines="6">{{ $quoted->plainText() }}</native:text>
+            @php($quoteTranslationEligible = ! $static && $quoted->canTranslateBy($viewer ?? app(\App\Devnull\Account::class)->user()))
+            @php($quoteTranslated = $quoteTranslationEligible && $quoted->translation->isDisplayed(app(\App\Devnull\TranslationLanguage::class)->yours(), app(\App\Devnull\Account::class)->automaticTranslation(), $translationDisplay[$quoted->id] ?? null))
+            <native:text ref="quoted-body-{{ $quoted->id }}" class="w-full text-[15px] leading-relaxed text-theme-ink" :max-lines="6">{{ ($quoteTranslated ? $quoted->displayingTranslation() : $quoted)->plainText() }}</native:text>
+            @include('native.partials.commit-translation-controls', ['commit' => $quoted, 'translationEligible' => $quoteTranslationEligible, 'translated' => $quoteTranslated])
             @if ($quoted->poll)
                 @include('native.partials.commit-poll', ['commit' => $quoted, 'static' => true])
             @endif
diff --git a/resources/views/native/partials/translation-language-sheet.blade.php b/resources/views/native/partials/translation-language-sheet.blade.php
new file mode 100644
index 0000000..0d98c17
--- /dev/null
+++ b/resources/views/native/partials/translation-language-sheet.blade.php
@@ -0,0 +1,44 @@
+{{-- Only 50 matching rows are mounted at once; search includes English and native language names. --}}
+<native:bottom-sheet ref="translation-language-sheet" :visible="$pickingTranslationLanguage" detents="large" @dismiss="translationLanguageSheetClosed">
+    <native:column class="w-full flex-1">
+        <native:column class="w-full px-5 pt-6 pb-3 gap-3">
+            <native:text font="semibold" class="text-lg text-theme-ink">Translation language</native:text>
+            <native:outlined-text-input ref="translation-language-search" class="w-full" label="Find a language" native:model.debounce.300ms="translationLanguageQuery" a11y-label="Find a language" />
+        </native:column>
+        <native:scroll-view ref="translation-language-list" class="w-full flex-1">
+            <native:column class="w-full pb-10">
+                <native:pressable ref="translation-language-phone" @press="chooseTranslationLanguage(null)" a11y-label="Use phone language{{ $chosenTranslationLanguage === null ? ', selected' : '' }}">
+                    <native:row class="w-full px-5 py-4 gap-3 items-center">
+                        <native:column :width="16">
+                            @if ($chosenTranslationLanguage === null)
+                                <native:icon :ios="\App\Icons\Lucide::Check->ios()" :android="\App\Icons\Lucide::Check->android()" :size="16" class="text-theme-primary" />
+                            @endif
+                        </native:column>
+                        <native:text class="flex-1 text-[15px] text-theme-ink">Use phone language</native:text>
+                    </native:row>
+                </native:pressable>
+                @forelse ($translationLanguages as $language)
+                    <native:column class="w-full h-[1] bg-theme-hairline" />
+                    <native:pressable ref="translation-language-{{ $language['code'] }}" @press="chooseTranslationLanguage('{{ $language['code'] }}')" a11y-label="{{ $language['name'] }} {{ $language['native_name'] }}{{ $language['code'] === $chosenTranslationLanguage ? ', selected' : '' }}">
+                        <native:row class="w-full px-5 py-3 gap-3 items-center">
+                            <native:column :width="16">
+                                @if ($language['code'] === $chosenTranslationLanguage)
+                                    <native:icon :ios="\App\Icons\Lucide::Check->ios()" :android="\App\Icons\Lucide::Check->android()" :size="16" class="text-theme-primary" />
+                                @endif
+                            </native:column>
+                            <native:column class="flex-1 gap-[2]">
+                                <native:text class="text-[15px] text-theme-ink">{{ $language['name'] }}</native:text>
+                                <native:text class="text-xs text-theme-ink-muted">{{ $language['native_name'] }}</native:text>
+                            </native:column>
+                        </native:row>
+                    </native:pressable>
+                @empty
+                    <native:text ref="translation-language-none" class="w-full px-5 py-6 text-sm text-theme-ink-muted">No language matches "{{ trim($translationLanguageQuery) }}".</native:text>
+                @endforelse
+                @if ($translationLanguagesMore > 0)
+                    <native:text ref="translation-language-more" class="w-full px-5 py-4 text-sm text-theme-ink-muted">{{ $translationLanguagesMore }} more. Keep typing to find yours.</native:text>
+                @endif
+            </native:column>
+        </native:scroll-view>
+    </native:column>
+</native:bottom-sheet>
diff --git a/resources/views/native/this-device.blade.php b/resources/views/native/this-device.blade.php
index 5f22838..ebe78d1 100644
--- a/resources/views/native/this-device.blade.php
+++ b/resources/views/native/this-device.blade.php
@@ -165,6 +165,27 @@
                     </native:column>
                 </native:column>
 
+                @if ($translationSettingsAvailable)
+                    <native:column ref="translation-settings" class="w-full pt-10">
+                        @include('native.partials.settings-heading', [
+                            'title' => 'Translations',
+                            'description' => 'Read commits in your preferred language. Available translations can appear automatically; new translations are only made when you tap Translate.',
+                        ])
+                        <native:column class="w-full px-4 pt-4 gap-3">
+                            <native:text ref="chosen-translation-language" class="text-sm text-theme-ink">{{ $translationLanguageName }}</native:text>
+                            <native:button ref="choose-translation-language" variant="secondary" size="lg" :ios-icon-trailing="Lucide::ChevronRight->ios()" :android-icon-trailing="Lucide::ChevronRight->android()" @press="pickTranslationLanguage" class="w-full">Choose translation language</native:button>
+                            <native:button ref="save-translation-language" :variant="$myColour" size="lg" :loading="$savingTranslationLanguage" :disabled="$savingTranslationLanguage || $chosenTranslationLanguage === $savedTranslationLanguage" @press="saveTranslationLanguage" class="w-full">Save translation language</native:button>
+                            <native:row class="w-full gap-6 items-center">
+                                <native:text class="flex-1 text-sm text-theme-ink">Automatically show available translations</native:text>
+                                <native:toggle ref="automatic-translation-switch" :value="$automaticTranslation" :disabled="$savingAutomaticTranslation" @change="setAutomaticTranslation" a11y-label="Automatically show available translations" />
+                            </native:row>
+                            @if ($translationSettingsError)
+                                <native:text ref="translation-settings-error" class="text-sm text-theme-destructive">{{ $translationSettingsError }}</native:text>
+                            @endif
+                        </native:column>
+                    </native:column>
+                @endif
+
                 {{--
                     The web's pastéis mode section, word for word: its heading and two lines, with the switch beside them.
                     The switch is the system's own (a UISwitch on iOS), which takes taps since NativePHP/mobile-air#545.
@@ -374,4 +395,7 @@
     {{-- After the page, so the rows it adds and takes away never change the ids of the page's own nodes, which would
          scroll it back to the top. --}}
     @include('native.partials.timezone-sheet')
+    @if ($translationSettingsAvailable)
+        @include('native.partials.translation-language-sheet')
+    @endif
 </native:column>
diff --git a/tests/Feature/CommitTranslationsTest.php b/tests/Feature/CommitTranslationsTest.php
new file mode 100644
index 0000000..98cb19d
--- /dev/null
+++ b/tests/Feature/CommitTranslationsTest.php
@@ -0,0 +1,302 @@
+<?php
+
+use App\Devnull\Account;
+use App\Devnull\Data\Commit;
+use App\Devnull\Data\User;
+use App\Devnull\ResponseCache;
+use Illuminate\Support\Facades\Http;
+use Native\Mobile\Events\Async\AsyncTaskFinished;
+use Native\Mobile\Support\AsyncTaskRunner;
+use Native\Mobile\Support\AsyncTaskTransport;
+use Native\Mobile\Testing\Native;
+use Native\Mobile\Testing\TestableComponent;
+
+beforeEach(function () {
+    config(['devnull.url' => 'http://devnull.test']);
+    signIn();
+    app(Account::class)->rememberTranslationSettings(['translation_language' => 'en']);
+});
+
+/** @return array<string, mixed> */
+function translationJson(bool $translated = false): array
+{
+    return [
+        'language' => 'en', 'source_language' => 'fr', 'source_name' => 'French', 'available' => true,
+        'translated' => $translated ? ['body_segments' => [['type' => 'text', 'text' => 'Hello https://translated.test']], 'preview_segments' => null] : null,
+    ];
+}
+
+it('only generates on request and keeps original overrides when shared cached translations arrive', function () {
+    $commit = commitJson(['id' => 'c1', 'body' => 'Bonjour', 'author' => userJson(['id' => 'other']), 'translation' => translationJson()]);
+    serveApi([
+        'GET /api/v1/log/following' => [pageJson([$commit])],
+        'GET /api/v1/commits/c1/translation' => [['translation' => translationJson(true)]],
+        'POST /api/v1/commits/c1/translation' => [['translation' => translationJson(true)]],
+    ]);
+    $screen = Native::visit('/log', platform: 'android');
+    Http::assertNotSent(fn ($request): bool => $request->method() === 'POST' && str_contains($request->url(), '/translation'));
+    $shown = $screen->get('commits')[0];
+    expect($screen->instance()->isTranslated($shown))->toBeTrue()
+        ->and($shown->body)->toBe('Bonjour');
+
+    $screen->call('showOriginal', 'c1')->call('onResume');
+    expect($screen->instance()->isTranslated($screen->get('commits')[0]))->toBeFalse();
+    $screen->call('translateCommit', 'c1');
+    expect($screen->instance()->isTranslated($screen->get('commits')[0]))->toBeTrue();
+    Http::assertNotSent(fn ($request): bool => $request->method() === 'POST' && str_contains($request->url(), '/translation'));
+});
+
+it('deduplicates generation and ignores its answer after the preferred language changes', function () {
+    $commit = commitJson(['id' => 'c1', 'body' => 'Bonjour', 'author' => userJson(['id' => 'other']), 'translation' => translationJson()]);
+    keep('log/following', pageJson([$commit]));
+    serveApi([
+        'GET /api/v1/log/following' => [pageJson([$commit])],
+        'POST /api/v1/commits/c1/translation' => [['translation' => translationJson(true)]],
+    ]);
+    holdRefreshes();
+    $screen = Native::visit('/log', platform: 'android')->call('translateCommit', 'c1');
+    $sent = refreshesSent($screen);
+    $screen->call('translateCommit', 'c1');
+    expect(refreshesSent($screen))->toBe($sent)
+        ->and($screen->get('translating'))->toHaveKey('c1');
+
+    app(Account::class)->rememberTranslationSettings(['translation_language' => 'de']);
+    finishRefreshes($screen);
+    expect($screen->get('translating'))->toBe([])
+        ->and($screen->instance()->isTranslated($screen->get('commits')[0]))->toBeFalse()
+        ->and(kept('log/following')['data'][0]['translation']['translated'])->toBeNull();
+});
+
+it('never offers translation for own deleted unavailable or old-backend commits', function () {
+    $screen = Native::visit('/log', platform: 'android');
+    foreach ([
+        commitJson(['author' => userJson(['id' => app(Account::class)->user()->id]), 'translation' => translationJson()]),
+        commitJson(['deleted_at' => '2026-01-01', 'translation' => translationJson()]),
+        commitJson(['translation' => [...translationJson(), 'available' => false]]),
+        commitJson(),
+    ] as $json) {
+        expect($screen->instance()->canTranslate(Commit::fromArray($json)))->toBeFalse();
+    }
+});
+
+/** Completes only the selected translation request, allowing deterministic out-of-order replies. */
+function finishTranslationRequest(TestableComponent $screen, string $method): void
+{
+    foreach ($screen->bridge()->callsTo('AsyncTask.Dispatch') as $call) {
+        $id = $call['params']['id'];
+        $payload = AsyncTaskTransport::readPayload($id);
+        $work = $payload === null ? [] : unserialize($payload);
+        $args = $work['args'] ?? [];
+
+        if (($args[2] ?? null) === $method && str_contains($args[0] ?? '', '/translation')) {
+            $result = AsyncTaskRunner::normalizeResult(AsyncTaskRunner::invoke($work));
+            $screen->emitNative(AsyncTaskFinished::class, ['id' => $id, 'result' => $result]);
+
+            return;
+        }
+    }
+
+    throw new RuntimeException('No pending '.$method.' translation request.');
+}
+
+it('does not let an older cache read erase a successful explicit generation', function () {
+    $commit = commitJson(['id' => 'c1', 'body' => 'Bonjour', 'author' => userJson(['id' => 'other']), 'translation' => translationJson()]);
+    serveApi([
+        'GET /api/v1/log/following' => [pageJson([$commit])],
+        'GET /api/v1/commits/c1/translation' => [['translation' => translationJson()]],
+        'POST /api/v1/commits/c1/translation' => [['translation' => translationJson(true)]],
+    ]);
+    keep('log/following', pageJson([$commit]));
+    holdRefreshes();
+    $screen = Native::visit('/log', platform: 'android');
+    // Resume settings refresh succeeds before the log's refresh, starting the cache read.
+    serveApi([
+        'GET /api/v1/me/settings' => [['data' => ['automatic_translation' => true]]],
+        'GET /api/v1/commits/c1/translation' => [['translation' => translationJson()]],
+        'POST /api/v1/commits/c1/translation' => [['translation' => translationJson(true)]],
+    ]);
+    $screen->call('onResume');
+    foreach ($screen->bridge()->callsTo('AsyncTask.Dispatch') as $call) {
+        $payload = AsyncTaskTransport::readPayload($call['params']['id']);
+        $work = $payload === null ? [] : unserialize($payload);
+        if (str_ends_with($work['args'][0] ?? '', '/me/settings')) {
+            $result = AsyncTaskRunner::normalizeResult(AsyncTaskRunner::invoke($work));
+            $screen->emitNative(AsyncTaskFinished::class, ['id' => $call['params']['id'], 'result' => $result]);
+        }
+    }
+    foreach ($screen->bridge()->callsTo('AsyncTask.Dispatch') as $call) {
+        $payload = AsyncTaskTransport::readPayload($call['params']['id']);
+        $work = $payload === null ? [] : unserialize($payload);
+        if (str_contains($work['args'][0] ?? '', '/translation')) {
+            $readId = $call['params']['id'];
+            $readWork = $work;
+            break;
+        }
+    }
+    $screen->call('translateCommit', 'c1');
+    finishTranslationRequest($screen, 'POST');
+    $screen->assertSee('Translated from French');
+    $result = AsyncTaskRunner::normalizeResult(AsyncTaskRunner::invoke($readWork));
+    $screen->emitNative(AsyncTaskFinished::class, ['id' => $readId, 'result' => $result]);
+    $screen->assertSee('Translated from French');
+    expect(kept('log/following')['data'][0]['translation']['translated'])->not->toBeNull();
+});
+
+it('renders translated links with their own indices and retains originals for excerpts', function () {
+    $commit = commitJson(['id' => 'c1', 'body' => 'Bonjour https://original.test', 'author' => userJson(['id' => 'other']), 'translation' => translationJson(true)]);
+    serveApi(['GET /api/v1/log/following' => [pageJson([$commit])]]);
+    $screen = Native::visit('/log', platform: 'android')->assertSee('Translated from French')->assertDontSee('Bonjour');
+    $screen->call('openLink', 'c1', 0);
+    expect($screen->bridge()->callsTo('Browser.OpenInApp')[0]['params']['url'] ?? null)->toBe('https://translated.test')
+        ->and($screen->get('commits')[0]->plainText())->toBe('Bonjour https://original.test');
+    $screen->tap('show-original-c1')->assertSee('Bonjour')->assertDontSee('Translated from French');
+    $screen->tap('translate-c1')->assertSee('Translated from French');
+    Http::assertNotSent(fn ($request): bool => str_contains($request->url(), '/translation'));
+});
+
+it('shows loading, retries failures, and rejects a generated answer for an edited body', function () {
+    $commit = commitJson(['id' => 'c1', 'body' => 'Bonjour', 'author' => userJson(['id' => 'other']), 'translation' => translationJson()]);
+    keep('log/following', pageJson([$commit]));
+    serveApi(['POST /api/v1/commits/c1/translation' => [['message' => 'Translation unavailable. Try again.'], 503]]);
+    holdRefreshes();
+    $screen = Native::visit('/log', platform: 'android')->tap('translate-c1')->assertSee('Translating…');
+    finishTranslationRequest($screen, 'POST');
+    $screen->assertSee('Translate')->assertDontSee('Translating…');
+    expect($screen->get('translating'))->toBe([]);
+
+    serveApi(['POST /api/v1/commits/c1/translation' => [['translation' => translationJson(true)]]]);
+    $screen->tap('translate-c1');
+    $edited = [...$commit, 'body' => 'Changed body'];
+    $screen->set('commits', [Commit::fromArray($edited)]);
+    keep('log/following', pageJson([$edited]));
+    finishTranslationRequest($screen, 'POST');
+    $screen->assertDontSee('Translated from French');
+    expect(kept('log/following')['data'][0]['translation']['translated'])->toBeNull();
+});
+
+it('patches nested quote and reply caches and clears dropped generation state on resume', function () {
+    $nested = commitJson(['id' => 'translated', 'body' => 'Bonjour', 'author' => userJson(['id' => 'other']), 'translation' => translationJson()]);
+    $outer = commitJson(['id' => 'outer', 'quoted_commit_id' => 'translated', 'quoted_commit' => $nested, 'reply_preview' => ['data' => [$nested], 'next_cursor' => null]]);
+    keep('log/following', pageJson([$outer]));
+    keep('commits/translated', ['data' => $nested]);
+    serveApi(['POST /api/v1/commits/translated/translation' => [['translation' => translationJson(true)]]]);
+    holdRefreshes();
+    $screen = Native::visit('/log', platform: 'android')->call('translateCommit', 'translated');
+    finishTranslationRequest($screen, 'POST');
+    expect($screen->get('commits')[0]->quotedCommit->translation->content)->not->toBeNull()
+        ->and($screen->get('commits')[0]->replyPreview->replies[0]->translation->content)->not->toBeNull()
+        ->and(kept('log/following')['data'][0]['reply_preview']['data'][0]['translation']['translated'])->not->toBeNull()
+        ->and(kept('log/following')['data'][0]['quoted_commit']['translation']['translated'])->not->toBeNull()
+        ->and(kept('commits/translated')['data']['translation']['translated'])->not->toBeNull();
+
+    $screen->set('translating', ['translated' => 'dropped'])->call('onResume')->assertSet('translating', []);
+});
+
+it('invalidates cached rows when automatic display changes and preserves explicit original overrides', function () {
+    $commit = commitJson(['id' => 'c1', 'body' => 'Bonjour', 'author' => userJson(['id' => 'other']), 'translation' => translationJson(true)]);
+    serveApi(['GET /api/v1/log/following' => [pageJson([$commit])]]);
+    $screen = Native::visit('/log', platform: 'android')->assertSee('Translated from French');
+    app(Account::class)->rememberTranslationSettings(['automatic_translation' => false]);
+    $screen->call('showMore', 'c1')->assertDontSee('Translated from French')->assertSee('Bonjour');
+    $screen->tap('translate-c1')->assertSee('Translated from French')->tap('show-original-c1')->assertSee('Bonjour');
+    app(Account::class)->rememberTranslationSettings(['automatic_translation' => true]);
+    $screen->call('showMore', 'c1')->assertDontSee('Translated from French');
+});
+
+it('preserves explicit generation when an older enclosing resource lands after a cache miss', function (string $screenType, bool $nested) {
+    $commit = commitJson(['id' => 'c1', 'body' => 'Bonjour', 'author' => userJson(['id' => 'other']), 'translation' => translationJson()]);
+    $outer = $nested ? commitJson(['id' => 'outer', 'quoted_commit_id' => 'c1', 'quoted_commit' => $commit, 'reply_preview' => ['data' => [$commit], 'next_cursor' => null]]) : $commit;
+    $path = $screenType === 'feed' ? 'log/following' : 'commits/'.$outer['id'];
+    $resource = $screenType === 'feed' ? pageJson([$outer]) : commitPageJson($outer);
+    serveApi([
+        'GET /api/v1/'.$path => [$resource],
+        'GET /api/v1/commits/c1/translation' => [['translation' => translationJson()]],
+        'POST /api/v1/commits/c1/translation' => [['translation' => translationJson(true)]],
+    ]);
+    holdRefreshes();
+    $screen = Native::visit($screenType === 'feed' ? '/log' : '/log/commits/'.$outer['id'], platform: 'android');
+    finishRefreshes($screen);
+    $screen->assertDontSee('Translated from French');
+    Http::assertSent(fn ($request): bool => $request->method() === 'GET' && str_contains($request->url(), '/commits/c1/translation'));
+
+    $screen->call('retry');
+    foreach ($screen->bridge()->callsTo('AsyncTask.Dispatch') as $call) {
+        $payload = AsyncTaskTransport::readPayload($call['params']['id']);
+        $work = $payload === null ? [] : unserialize($payload);
+        if (parse_url($work['args'][0] ?? '', PHP_URL_PATH) === '/api/v1/'.$path) {
+            $resourceId = $call['params']['id'];
+            $resourceWork = $work;
+        }
+    }
+    $screen->call('translateCommit', 'c1');
+    finishTranslationRequest($screen, 'POST');
+    $screen->assertSee('Translated from French');
+    $result = AsyncTaskRunner::normalizeResult(AsyncTaskRunner::invoke($resourceWork));
+    $screen->emitNative(AsyncTaskFinished::class, ['id' => $resourceId, 'result' => $result])->assertSee('Translated from French');
+    $kept = kept($path)['data'];
+    $cachedCommit = $screenType === 'feed' ? $kept[0] : ($kept['commit'] ?? $kept);
+    expect(($nested ? $cachedCommit['quoted_commit'] : $cachedCommit)['translation']['translated'])->not->toBeNull();
+    if ($nested) {
+        expect($cachedCommit['reply_preview']['data'][0]['translation']['translated'])->not->toBeNull();
+    }
+})->with([
+    'feed' => ['feed', false],
+    'nested feed' => ['feed', true],
+    'detail' => ['detail', false],
+    'nested detail' => ['detail', true],
+]);
+
+it('invalidates successful-generation protection on body account or target preference changes', function () {
+    $cache = app(ResponseCache::class);
+    $commit = commitJson(['id' => 'c1', 'body' => 'Bonjour', 'author' => userJson(['id' => 'other']), 'translation' => translationJson()]);
+    $before = microtime(true) - 1;
+    $cache->rememberGeneratedTranslation('c1', 'Bonjour', translationJson(true));
+    expect($cache->preserveGeneratedTranslations($commit, $before)['translation']['translated'])->not->toBeNull()
+        ->and($cache->preserveGeneratedTranslations($commit, microtime(true) + 1)['translation']['translated'])->toBeNull();
+    $cache->preserveGeneratedTranslations([...$commit, 'body' => 'Edited'], $before);
+    expect($cache->preserveGeneratedTranslations($commit, $before)['translation']['translated'])->toBeNull();
+
+    $cache->rememberGeneratedTranslation('c1', 'Bonjour', translationJson(true));
+    app(Account::class)->rememberTranslationSettings(['translation_language' => 'de']);
+    app(Account::class)->rememberTranslationSettings(['translation_language' => 'en']);
+    expect($cache->preserveGeneratedTranslations($commit, $before)['translation']['translated'])->toBeNull();
+
+    $cache->rememberGeneratedTranslation('c1', 'Bonjour', translationJson(true));
+    $originalUser = app(Account::class)->user();
+    app(Account::class)->remember(User::fromArray(userJson(['id' => 'different'])));
+    app(Account::class)->remember($originalUser);
+    expect($cache->preserveGeneratedTranslations($commit, $before)['translation']['translated'])->toBeNull();
+});
+
+it('renders only truncated translated code until the collapsed card is expanded', function () {
+    $translation = [...translationJson(true), 'translated' => [
+        'body_segments' => [['type' => 'block', 'language' => 'php', 'html' => '<pre><code>first line'."\n".'full-only last line</code></pre>']],
+        'preview_segments' => [['type' => 'block', 'language' => 'php', 'html' => '<pre><code>first line'."\n".'…</code></pre>']],
+    ]];
+    $commit = commitJson(['id' => 'c1', 'body' => 'Bonjour', 'author' => userJson(['id' => 'other']), 'translation' => $translation]);
+    serveApi(['GET /api/v1/log/following' => [pageJson([$commit])]]);
+    Native::visit('/log', platform: 'android')->assertSee('first line')->assertDontSee('full-only last line')
+        ->tap('show-more-c1')->assertSee('full-only last line');
+});
+
+it('keeps translated quoted excerpts compact with independent controls and original static composer text', function (string $screenType) {
+    $quoted = commitJson(['id' => 'c1', 'body' => 'Bonjour original', 'author' => userJson(['id' => 'other']), 'translation' => translationJson(true)]);
+    $outer = commitJson(['id' => 'outer', 'quoted_commit_id' => 'c1', 'quoted_commit' => $quoted]);
+    serveApi(['GET /api/v1/commits/outer' => [commitPageJson($outer)], 'GET /api/v1/log/following' => [pageJson([$outer])]]);
+    $screen = Native::visit($screenType === 'feed' ? '/log' : '/log/commits/outer', platform: 'android')->assertSee('Translated from French');
+    expect(nodeByRef($screen, 'quoted-body-c1')['props']['max_lines'])->toBe(6);
+    $screen->tap('show-original-c1')->assertSee('Bonjour original')->assertDontSee('Translated from French');
+    expect($screen->navigationIntent())->toBeNull();
+    $screen->tap('translate-c1')->assertSee('Translated from French');
+    expect($screen->navigationIntent())->toBeNull()
+        ->and(nodeByRef($screen, 'quoted-body-c1')['props']['max_lines'])->toBe(6);
+    Http::assertNotSent(fn ($request): bool => str_contains($request->url(), '/translation'));
+
+    $screen->call('quoteCommit', 'c1');
+    $static = nodeByRef($screen, 'quote-card');
+    expect(treeShows($static, 'Bonjour original'))->toBeTrue()
+        ->and(treeShows($static, 'Translated from French'))->toBeFalse()
+        ->and(findNode($static, fn (array $node): bool => ($node['ref'] ?? null) === 'show-original-c1'))->toBeNull();
+    $screen->dismissSheet('sheet')->tap('quoted-outer')->assertNavigatedTo('/log/commits/c1');
+    expect($screen->navigationIntent()->data['commit']->body)->toBe('Bonjour original');
+})->with(['feed', 'detail']);
diff --git a/tests/Feature/Screens/ProfileTest.php b/tests/Feature/Screens/ProfileTest.php
index eea451e..c8002da 100644
--- a/tests/Feature/Screens/ProfileTest.php
+++ b/tests/Feature/Screens/ProfileTest.php
@@ -219,7 +219,8 @@ function adaCommitJson(array $overrides = []): array
         ->follow()
         ->goBack();
 
-    Http::assertSentCount(7);
+    Http::assertSentCount(8);
+    Http::assertSent(fn ($request): bool => str_ends_with($request->url(), '/me/settings'));
 });
 
 it('shows the pinned commit above the rest, marked as pinned', function () {
diff --git a/tests/Feature/TranslationPreferencesTest.php b/tests/Feature/TranslationPreferencesTest.php
new file mode 100644
index 0000000..c9c3a91
--- /dev/null
+++ b/tests/Feature/TranslationPreferencesTest.php
@@ -0,0 +1,154 @@
+<?php
+
+use App\Devnull\Account;
+use App\Devnull\Client;
+use App\Devnull\TranslationLanguage;
+use App\NativeComponents\ThisDevice;
+use Illuminate\Support\Facades\Http;
+use Native\Mobile\Events\Async\AsyncTaskFinished;
+use Native\Mobile\Support\AsyncTaskTransport;
+use Native\Mobile\Testing\Native;
+
+it('defaults automatic display on and preserves translation preferences across partial settings answers', function () {
+    $account = app(Account::class);
+    expect($account->automaticTranslation())->toBeTrue()
+        ->and($account->translationLanguage())->toBeNull();
+
+    $languages = [['code' => 'pt', 'name' => 'Portuguese', 'native_name' => 'Português']];
+    $account->rememberTranslationSettings([
+        'translation_language' => 'pt',
+        'automatic_translation' => false,
+        'translation_languages' => [...$languages, null, ['code' => 7]],
+    ]);
+    $account->rememberTranslationSettings(['timezone' => 'Europe/Lisbon']);
+
+    expect($account->translationLanguage())->toBe('pt')
+        ->and($account->automaticTranslation())->toBeFalse()
+        ->and($account->translationLanguages())->toBe($languages);
+
+    $account->rememberTranslationSettings(['translation_language' => null, 'automatic_translation' => true]);
+    expect($account->translationLanguage())->toBeNull()
+        ->and($account->automaticTranslation())->toBeTrue();
+});
+
+it('clears account translation preferences on signout', function () {
+    $account = app(Account::class);
+    $account->rememberTranslationSettings(['translation_language' => 'fr', 'automatic_translation' => false]);
+    $account->forget();
+
+    expect($account->translationLanguage())->toBeNull()
+        ->and($account->automaticTranslation())->toBeTrue()
+        ->and($account->translationLanguages())->toBe([]);
+});
+
+it('uses the phone primary language or English and sends it on signed requests', function () {
+    config(['devnull.url' => 'http://devnull.test']);
+    signIn();
+    Native::fakeBridge()->respondTo('Device.GetInfo', ['info' => json_encode(['language' => 'pt-BR'])]);
+    app()->forgetInstance(TranslationLanguage::class);
+    $client = app(Client::class);
+
+    expect($client->signedGet('log/recent')->headers['Accept-Language'])->toBe('pt')
+        ->and($client->signedWrite('POST', Client::translationPath('a/b'), ['language' => 'pt'])->url)->toEndWith('/commits/a%2Fb/translation');
+
+    app(Account::class)->rememberTranslationSettings(['translation_language' => 'fr']);
+    expect($client->signedGet('log/recent')->headers['Accept-Language'])->toBe('fr');
+
+    app(Account::class)->rememberTranslationSettings(['translation_language' => null, 'translation_languages' => [['code' => 'en', 'name' => 'English', 'native_name' => 'English']]]);
+    expect($client->signedGet('log/recent')->headers['Accept-Language'])->toBe('en');
+});
+
+it('searches English and native language names and saves sent preferences despite a me-only response', function () {
+    config(['devnull.url' => 'http://devnull.test']);
+    signIn();
+    $languages = [
+        ['code' => 'en', 'name' => 'English', 'native_name' => 'English'],
+        ['code' => 'de', 'name' => 'German', 'native_name' => 'Deutsch'],
+    ];
+    serveApi([
+        'GET /api/v1/me' => [currentUserJson()],
+        'GET /api/v1/me/settings' => [['data' => ['translation_language' => null, 'automatic_translation' => true, 'translation_languages' => $languages]]],
+        'PUT /api/v1/me/translation-language' => [currentUserJson()],
+        'PUT /api/v1/me/automatic-translation' => [currentUserJson()],
+    ]);
+    $screen = Native::test(ThisDevice::class);
+    $screen->set('translationLanguageQuery', 'Deutsch');
+    expect($screen->instance()->translationLanguages())->toBe([$languages[1]]);
+    $screen->set('translationLanguageQuery', 'German');
+    expect($screen->instance()->translationLanguages())->toBe([$languages[1]]);
+
+    $screen->call('chooseTranslationLanguage', 'de')->call('saveTranslationLanguage')->call('setAutomaticTranslation', false);
+    expect(app(Account::class)->translationLanguage())->toBe('de')
+        ->and(app(Account::class)->automaticTranslation())->toBeFalse()
+        ->and($screen->get('savedTranslationLanguage'))->toBe('de');
+    Http::assertSent(fn ($request): bool => $request->method() === 'PUT' && str_ends_with($request->url(), '/me/translation-language') && $request['translation_language'] === 'de');
+    Http::assertSent(fn ($request): bool => $request->method() === 'PUT' && str_ends_with($request->url(), '/me/automatic-translation') && $request['enabled'] === false);
+});
+
+it('renders a bounded searchable language picker and hides unsupported settings on older servers', function () {
+    config(['devnull.url' => 'http://devnull.test']);
+    signIn();
+    serveApi(['GET /api/v1/me' => [currentUserJson()], 'GET /api/v1/me/settings' => [['data' => ['timezone' => null]]]]);
+    Native::test(ThisDevice::class)->assertDontSee('Choose translation language');
+    $languages = array_map(fn (int $index): array => ['code' => 'l'.$index, 'name' => 'Language '.$index, 'native_name' => 'Native '.$index], range(1, 125));
+    app(Account::class)->rememberTranslationSettings(['translation_languages' => $languages]);
+    $screen = Native::test(ThisDevice::class)->tap('choose-translation-language')->assertSee('Translation language')->assertSee('75 more. Keep typing to find yours.');
+    expect($screen->instance()->translationLanguages())->toHaveCount(50);
+    $screen->input('translation-language-search', 'Native 125')->assertSee('Language 125');
+    expect($screen->instance()->translationLanguages())->toHaveCount(1);
+    $screen->tap('translation-language-l125')->assertSet('chosenTranslationLanguage', 'l125')->assertSet('pickingTranslationLanguage', false);
+});
+
+it('restores automatic display and leaves the language retryable when saves fail', function () {
+    config(['devnull.url' => 'http://devnull.test']);
+    signIn();
+    serveApi([
+        'GET /api/v1/me' => [currentUserJson()],
+        'GET /api/v1/me/settings' => [['data' => ['translation_languages' => [['code' => 'de', 'name' => 'German', 'native_name' => 'Deutsch']]]]],
+        'PUT /api/v1/me/automatic-translation' => [['message' => 'Try again.'], 503],
+        'PUT /api/v1/me/translation-language' => [['message' => 'Try again.'], 503],
+    ]);
+    $screen = Native::test(ThisDevice::class)->call('setAutomaticTranslation', false)->assertSet('automaticTranslation', true)->assertSee('Try again.');
+    $screen->call('chooseTranslationLanguage', 'de')->call('saveTranslationLanguage')->assertSet('savingTranslationLanguage', false)->assertSet('savedTranslationLanguage', null)->assertSet('chosenTranslationLanguage', 'de');
+    expect(app(Account::class)->translationLanguage())->toBeNull();
+});
+
+it('recovers dropped preference writes on Account resume and ignores obsolete callbacks', function (string $setting) {
+    config(['devnull.url' => 'http://devnull.test']);
+    signIn();
+    $languages = [
+        ['code' => 'de', 'name' => 'German', 'native_name' => 'Deutsch'],
+        ['code' => 'fr', 'name' => 'French', 'native_name' => 'Français'],
+    ];
+    serveApi([
+        'GET /api/v1/me' => [currentUserJson()],
+        'GET /api/v1/me/settings' => [['data' => ['translation_language' => null, 'automatic_translation' => true, 'translation_languages' => $languages]]],
+    ]);
+    holdRefreshes();
+    $screen = Native::test(ThisDevice::class);
+    finishRefreshes($screen);
+    if ($setting === 'language') {
+        $screen->call('chooseTranslationLanguage', 'de')->call('saveTranslationLanguage')->assertSet('savingTranslationLanguage', true);
+    } else {
+        $screen->call('setAutomaticTranslation', false)->assertSet('savingAutomaticTranslation', true);
+    }
+    foreach ($screen->bridge()->callsTo('AsyncTask.Dispatch') as $call) {
+        $payload = AsyncTaskTransport::readPayload($call['params']['id']);
+        $work = $payload === null ? [] : unserialize($payload);
+        if (($work['args'][2] ?? null) === 'PUT') {
+            $obsoleteId = $call['params']['id'];
+        }
+    }
+    // Its completion was dropped off-screen; the fresh server state may also reflect a later settings change.
+    serveApi([
+        'GET /api/v1/me' => [currentUserJson()],
+        'GET /api/v1/me/settings' => [['data' => ['translation_language' => 'fr', 'automatic_translation' => true, 'translation_languages' => $languages]]],
+    ]);
+    $screen->call('onResume')->assertSet('savingTranslationLanguage', false)->assertSet('savingAutomaticTranslation', false);
+    finishRefreshes($screen);
+    $screen->assertSet('savedTranslationLanguage', 'fr')->assertSet('chosenTranslationLanguage', 'fr')->assertSet('automaticTranslation', true);
+    $screen->emitNative(AsyncTaskFinished::class, ['id' => $obsoleteId, 'result' => ['status' => 200, 'from_devnull' => true, 'json' => currentUserJson()]]);
+    expect(app(Account::class)->translationLanguage())->toBe('fr')
+        ->and(app(Account::class)->automaticTranslation())->toBeTrue();
+    $screen->assertSet('savedTranslationLanguage', 'fr')->assertSet('automaticTranslation', true);
+})->with(['language', 'automatic']);
diff --git a/tests/Unit/CommitTranslationTest.php b/tests/Unit/CommitTranslationTest.php
new file mode 100644
index 0000000..b54c5e2
--- /dev/null
+++ b/tests/Unit/CommitTranslationTest.php
@@ -0,0 +1,41 @@
+<?php
+
+use App\Devnull\Data\Commit;
+use App\Devnull\Data\CommitTranslation;
+
+it('keeps translated rich content separate from original excerpts and links', function () {
+    $commit = Commit::fromArray([
+        'id' => 'translated',
+        'body' => 'Bonjour https://original.test',
+        'translation' => [
+            'language' => 'en',
+            'source_language' => 'fr',
+            'source_name' => 'French',
+            'available' => true,
+            'translated' => [
+                'body_segments' => [
+                    ['type' => 'text', 'text' => 'Hello https://translated.test '],
+                    ['type' => 'code', 'code' => 'literal()'],
+                    ['type' => 'block', 'language' => 'php', 'html' => '<pre><code><span>&lt;?php</span> echo &quot;hi&quot;;</code></pre>'],
+                ],
+                'preview_segments' => [['type' => 'text', 'text' => 'Hello…']],
+            ],
+        ],
+    ]);
+
+    expect($commit->body)->toBe('Bonjour https://original.test')
+        ->and($commit->plainText())->toBe('Bonjour https://original.test')
+        ->and($commit->links()[0]->href)->toBe('https://original.test')
+        ->and($commit->translation->sourceName)->toBe('French')
+        ->and($commit->translation->content[0]->runs[1]->link->href)->toBe('https://translated.test')
+        ->and($commit->translation->content[1]->code)->toBe('<?php echo "hi";')
+        ->and($commit->translation->previewContent[0]->runs[0]->text)->toBe('Hello…')
+        ->and($commit->withStar(true)->translation)->toBe($commit->translation);
+});
+
+it('tolerates absent translations and cache misses without inventing content', function () {
+    expect(Commit::fromArray(['body' => 'original'])->translation)->toBeNull()
+        ->and(CommitTranslation::fromArray([]))->toBeNull()
+        ->and(CommitTranslation::fromArray(['language' => 'en', 'available' => true, 'translated' => null])->content)->toBeNull()
+        ->and(Commit::fromArray(['body' => 'original', 'deleted_at' => '2026-01-01', 'translation' => ['language' => 'en']])->translation)->toBeNull();
+});