diff --git a/backend/__tests__/utils/feedbackReactions.test.js b/backend/__tests__/utils/feedbackReactions.test.js
new file mode 100644
index 00000000..b45f2861
--- /dev/null
+++ b/backend/__tests__/utils/feedbackReactions.test.js
@@ -0,0 +1,202 @@
+/**
+ * Emoji reactions (#839) — pins the contract of the `reaction` feedback type:
+ *  - only emojis from the fixed curated set are accepted
+ *  - one reaction per guest per photo: same emoji again toggles OFF,
+ *    a different emoji SWITCHES the existing row (never a second row)
+ *  - per-guest scoping mirrors likes: guest_id when present, else the
+ *    device-hash guest_identifier — two token-guests on one device react
+ *    independently
+ *  - denormalized photos.reaction_count and the per-emoji tallies follow
+ *    visibility: hidden-by-moderator reactions disappear from both
+ *  - the long and pivoted exports carry the reaction
+ */
+
+const path = require('path');
+const fs = require('fs');
+const os = require('os');
+
+process.env.NODE_ENV = 'test';
+process.env.TEST_DATABASE_PATH = path.join(
+  fs.mkdtempSync(path.join(os.tmpdir(), 'picpeak-feedback-reactions-')), 'db.sqlite',
+);
+process.env.JWT_SECRET = process.env.JWT_SECRET || 'feedback-reactions-test-secret';
+
+const { bootCrmDb, seedMinimal } = require('../integration/helpers/crmDb');
+
+const feedbackService = require('../../src/services/feedbackService');
+const { REACTION_EMOJIS } = require('../../src/constants/reactions');
+
+const EVENT_SLUG = 'reactions-test-event';
+const GUEST_A = 'guest-a-identifier';
+const GUEST_B = 'guest-b-identifier';
+
+let db;
+let cleanup;
+let eventId;
+let photoIds;
+
+async function react(photoId, emoji, { guestIdentifier = GUEST_A, guestId = null } = {}) {
+  return feedbackService.submitFeedback(photoId, eventId, {
+    feedback_type: 'reaction',
+    reaction: emoji,
+    guest_id: guestId,
+    ip_address: '127.0.0.1',
+    user_agent: 'jest',
+  }, guestIdentifier);
+}
+
+async function reactionCountOf(photoId) {
+  const row = await db('photos').where('id', photoId).first();
+  return Number(row.reaction_count) || 0;
+}
+
+beforeAll(async () => {
+  ({ db, cleanup } = await bootCrmDb());
+  await seedMinimal(db);
+  const inserted = await db('events').insert({
+    slug: EVENT_SLUG,
+    event_type: 'wedding',
+    event_name: 'Reactions Test',
+    event_date: '2026-07-20',
+    host_email: 'host@example.com',
+    admin_email: 'admin@example.com',
+    password_hash: 'x',
+    share_link: `/gallery/${EVENT_SLUG}/share`,
+    share_token: 'reactions-test-share',
+    expires_at: new Date(Date.now() + 7 * 24 * 3600 * 1000).toISOString(),
+    is_active: 1,
+    is_archived: 0,
+    is_draft: 0,
+    created_at: new Date().toISOString(),
+  }).returning('id');
+  eventId = inserted[0]?.id ?? inserted[0];
+
+  photoIds = [];
+  for (let i = 0; i < 3; i++) {
+    const photo = await db('photos').insert({
+      event_id: eventId,
+      filename: `photo-${i}.jpg`,
+      path: `events/reactions/${i}.jpg`,
+      type: 'individual',
+      uploaded_at: new Date().toISOString(),
+    }).returning('id');
+    photoIds.push(photo[0]?.id ?? photo[0]);
+  }
+}, 120000);
+
+afterAll(async () => {
+  if (cleanup) await cleanup();
+});
+
+describe('reaction submission (#839)', () => {
+  it('rejects emojis outside the curated set', async () => {
+    await expect(react(photoIds[0], '🦄')).rejects.toThrow('Invalid reaction');
+    await expect(react(photoIds[0], undefined)).rejects.toThrow('Invalid reaction');
+    expect(await reactionCountOf(photoIds[0])).toBe(0);
+  });
+
+  it('creates a reaction row and maintains the denormalized count', async () => {
+    const result = await react(photoIds[0], '❤️');
+    expect(result.created).toBe(true);
+
+    const row = await db('photo_feedback')
+      .where({ photo_id: photoIds[0], feedback_type: 'reaction' })
+      .first();
+    expect(row.reaction).toBe('❤️');
+    expect(await reactionCountOf(photoIds[0])).toBe(1);
+    expect(await feedbackService.getPhotoReactionCounts(photoIds[0])).toEqual({ '❤️': 1 });
+  });
+
+  it('switches to another emoji in place — never a second row per guest', async () => {
+    const result = await react(photoIds[0], '🎉');
+    expect(result.updated).toBe(true);
+
+    const rows = await db('photo_feedback')
+      .where({ photo_id: photoIds[0], feedback_type: 'reaction' });
+    expect(rows).toHaveLength(1);
+    expect(rows[0].reaction).toBe('🎉');
+    expect(await feedbackService.getPhotoReactionCounts(photoIds[0])).toEqual({ '🎉': 1 });
+  });
+
+  it('tallies different guests per emoji', async () => {
+    await react(photoIds[0], '🎉', { guestIdentifier: GUEST_B });
+    expect(await feedbackService.getPhotoReactionCounts(photoIds[0])).toEqual({ '🎉': 2 });
+    expect(await reactionCountOf(photoIds[0])).toBe(2);
+  });
+
+  it('toggles off with the same emoji', async () => {
+    const result = await react(photoIds[0], '🎉');
+    expect(result.removed).toBe(true);
+    expect(await feedbackService.getPhotoReactionCounts(photoIds[0])).toEqual({ '🎉': 1 }); // GUEST_B remains
+    expect(await reactionCountOf(photoIds[0])).toBe(1);
+  });
+
+  it('scopes per guest_id when present — two token-guests on one device stay independent', async () => {
+    const first = await react(photoIds[1], '😍', { guestIdentifier: GUEST_A, guestId: 101 });
+    const second = await react(photoIds[1], '👏', { guestIdentifier: GUEST_A, guestId: 102 });
+    expect(first.created).toBe(true);
+    expect(second.created).toBe(true); // NOT treated as guest 101's switch
+    expect(await feedbackService.getPhotoReactionCounts(photoIds[1])).toEqual({ '😍': 1, '👏': 1 });
+  });
+
+  it('accepts every emoji of the curated set', async () => {
+    for (const emoji of REACTION_EMOJIS) {
+      const res = await react(photoIds[2], emoji, { guestIdentifier: `guest-${emoji}` });
+      expect(res.created).toBe(true);
+    }
+    const counts = await feedbackService.getPhotoReactionCounts(photoIds[2]);
+    expect(Object.keys(counts)).toHaveLength(REACTION_EMOJIS.length);
+  });
+
+  it('hidden reactions leave both the per-emoji tallies and reaction_count', async () => {
+    const row = await db('photo_feedback')
+      .where({ photo_id: photoIds[0], feedback_type: 'reaction' })
+      .first();
+    await feedbackService.moderateFeedback(row.id, 'hide', 1);
+
+    expect(await feedbackService.getPhotoReactionCounts(photoIds[0])).toEqual({});
+    expect(await reactionCountOf(photoIds[0])).toBe(0);
+
+    await feedbackService.moderateFeedback(row.id, 'approve', 1);
+    expect(await reactionCountOf(photoIds[0])).toBe(1);
+  });
+
+  it('toggle and switch collapse racy duplicate rows for the same guest', async () => {
+    // Simulate the check-then-insert race: two rows for one guest+photo.
+    const mk = (emoji) => ({
+      photo_id: photoIds[1], event_id: eventId, feedback_type: 'reaction',
+      reaction: emoji, guest_identifier: 'dup-guest', is_approved: true, is_hidden: false,
+      created_at: new Date(), updated_at: new Date(),
+    });
+    await db('photo_feedback').insert([mk('❤️'), mk('❤️')]);
+
+    // Switching converges to exactly ONE row with the new emoji…
+    const switched = await react(photoIds[1], '🎉', { guestIdentifier: 'dup-guest' });
+    expect(switched.updated).toBe(true);
+    let rows = await db('photo_feedback')
+      .where({ photo_id: photoIds[1], feedback_type: 'reaction', guest_identifier: 'dup-guest' });
+    expect(rows).toHaveLength(1);
+    expect(rows[0].reaction).toBe('🎉');
+
+    // …and toggle-off removes the full guest-scoped set.
+    await db('photo_feedback').insert(mk('🎉'));
+    const removed = await react(photoIds[1], '🎉', { guestIdentifier: 'dup-guest' });
+    expect(removed.removed).toBe(true);
+    rows = await db('photo_feedback')
+      .where({ photo_id: photoIds[1], feedback_type: 'reaction', guest_identifier: 'dup-guest' });
+    expect(rows).toHaveLength(0);
+  });
+
+  it('summary and exports carry reactions', async () => {
+    const summary = await feedbackService.getEventFeedbackSummary(eventId);
+    expect(Number(summary.stats.total_reactions)).toBeGreaterThan(0);
+
+    const longRows = await feedbackService.exportEventFeedback(eventId);
+    const longReaction = longRows.find((r) => r.feedback_type === 'reaction');
+    expect(longReaction.reaction).toBeTruthy();
+
+    const pivotRows = await feedbackService.exportEventFeedbackPivoted(eventId);
+    const pivotWithReaction = pivotRows.find((r) => r.reaction);
+    expect(REACTION_EMOJIS).toContain(pivotWithReaction.reaction);
+  });
+});
diff --git a/backend/migrations/core/164_add_emoji_reactions.js b/backend/migrations/core/164_add_emoji_reactions.js
new file mode 100644
index 00000000..8b0a0b4f
--- /dev/null
+++ b/backend/migrations/core/164_add_emoji_reactions.js
@@ -0,0 +1,55 @@
+/**
+ * Emoji reactions on photos (#839).
+ *
+ * - event_feedback_settings.allow_reactions: per-event toggle next to
+ *   allow_likes / allow_ratings / allow_comments. Defaults TRUE for parity
+ *   with the sibling toggles — the master feedback_enabled gate (default
+ *   false, opt-in per event) still decides whether any feedback UI shows.
+ * - photo_feedback.reaction: the emoji value for feedback_type='reaction'
+ *   rows (validated against the fixed set in constants/reactions.js).
+ * - photos.reaction_count: denormalized total, maintained by
+ *   updatePhotoFeedbackStats alongside like_count / favorite_count.
+ */
+
+exports.up = async function (knex) {
+  const hasAllowReactions = await knex.schema.hasColumn('event_feedback_settings', 'allow_reactions');
+  if (!hasAllowReactions) {
+    await knex.schema.alterTable('event_feedback_settings', (table) => {
+      table.boolean('allow_reactions').defaultTo(true);
+    });
+  }
+
+  const hasReaction = await knex.schema.hasColumn('photo_feedback', 'reaction');
+  if (!hasReaction) {
+    await knex.schema.alterTable('photo_feedback', (table) => {
+      // 16 chars: emoji are multi-byte/multi-codepoint (variation selectors),
+      // but well under 16 characters each.
+      table.string('reaction', 16);
+    });
+  }
+
+  const hasReactionCount = await knex.schema.hasColumn('photos', 'reaction_count');
+  if (!hasReactionCount) {
+    await knex.schema.alterTable('photos', (table) => {
+      table.integer('reaction_count').defaultTo(0);
+    });
+  }
+};
+
+exports.down = async function (knex) {
+  if (await knex.schema.hasColumn('photos', 'reaction_count')) {
+    await knex.schema.alterTable('photos', (table) => {
+      table.dropColumn('reaction_count');
+    });
+  }
+  if (await knex.schema.hasColumn('photo_feedback', 'reaction')) {
+    await knex.schema.alterTable('photo_feedback', (table) => {
+      table.dropColumn('reaction');
+    });
+  }
+  if (await knex.schema.hasColumn('event_feedback_settings', 'allow_reactions')) {
+    await knex.schema.alterTable('event_feedback_settings', (table) => {
+      table.dropColumn('allow_reactions');
+    });
+  }
+};
diff --git a/backend/src/constants/reactions.js b/backend/src/constants/reactions.js
new file mode 100644
index 00000000..513904ad
--- /dev/null
+++ b/backend/src/constants/reactions.js
@@ -0,0 +1,11 @@
+/**
+ * Emoji reactions (#839): the fixed, curated reaction set. Guests pick ONE
+ * of these per photo (changeable). Kept as a shared constant so the
+ * validator, the service and the export layer can never drift apart.
+ *
+ * Mirrored in frontend/src/services/feedback.service.ts (REACTION_EMOJIS) —
+ * update both together.
+ */
+const REACTION_EMOJIS = ['❤️', '😂', '😍', '👏', '🎉'];
+
+module.exports = { REACTION_EMOJIS };
diff --git a/backend/src/middleware/feedbackRateLimit.js b/backend/src/middleware/feedbackRateLimit.js
index 1c2bd13b..7dad144d 100644
--- a/backend/src/middleware/feedbackRateLimit.js
+++ b/backend/src/middleware/feedbackRateLimit.js
@@ -34,20 +34,26 @@ async function getRateLimitSettings() {
       .where('setting_key', 'feedback_rate_limits')
       .first();
     
-    if (settings && settings.setting_value) {
-      // setting_value is already a JSON object in PostgreSQL
-      return typeof settings.setting_value === 'string' 
-        ? JSON.parse(settings.setting_value)
-        : settings.setting_value;
-    }
-    
-    // Default settings
-    return {
+    // Defaults FIRST, stored values override: persisted rows predate newer
+    // action types (`reaction`, #839) — returning the stored object alone
+    // would silently drop their intended defaults to the generic 100/h.
+    const defaults = {
       rating: { max: 100, window: 3600 }, // 100 ratings per hour
       comment: { max: 20, window: 3600 }, // 20 comments per hour
       like: { max: 200, window: 3600 }, // 200 likes per hour
-      favorite: { max: 100, window: 3600 } // 100 favorites per hour
+      favorite: { max: 100, window: 3600 }, // 100 favorites per hour
+      reaction: { max: 200, window: 3600 } // reactions churn like likes (#839)
     };
+
+    if (settings && settings.setting_value) {
+      // setting_value is already a JSON object in PostgreSQL
+      const stored = typeof settings.setting_value === 'string'
+        ? JSON.parse(settings.setting_value)
+        : settings.setting_value;
+      return { ...defaults, ...stored };
+    }
+
+    return defaults;
   } catch (error) {
     logger.error('Error getting rate limit settings:', error);
     // Return defaults on error
@@ -55,7 +61,8 @@ async function getRateLimitSettings() {
       rating: { max: 100, window: 3600 },
       comment: { max: 20, window: 3600 },
       like: { max: 200, window: 3600 },
-      favorite: { max: 100, window: 3600 }
+      favorite: { max: 100, window: 3600 },
+      reaction: { max: 200, window: 3600 }
     };
   }
 }
diff --git a/backend/src/routes/adminEvents/crud.js b/backend/src/routes/adminEvents/crud.js
index 56b8252f..85f4f295 100644
--- a/backend/src/routes/adminEvents/crud.js
+++ b/backend/src/routes/adminEvents/crud.js
@@ -165,6 +165,7 @@ module.exports = (router) => {
         allow_likes = true,
         allow_comments = true,
         allow_favorites = true,
+        allow_reactions = true,
         require_name_email = false,
         moderate_comments = true,
         show_feedback_to_guests = true,
@@ -490,6 +491,7 @@ module.exports = (router) => {
           allow_likes: formatBoolean(allow_likes),
           allow_comments: formatBoolean(allow_comments),
           allow_favorites: formatBoolean(allow_favorites),
+          allow_reactions: formatBoolean(allow_reactions),
           require_name_email: formatBoolean(require_name_email),
           moderate_comments: formatBoolean(moderate_comments),
           show_feedback_to_guests: formatBoolean(show_feedback_to_guests),
@@ -1111,6 +1113,7 @@ module.exports = (router) => {
           allow_likes: sourceFeedback.allow_likes,
           allow_comments: sourceFeedback.allow_comments,
           allow_favorites: sourceFeedback.allow_favorites,
+          allow_reactions: sourceFeedback.allow_reactions,
           require_name_email: sourceFeedback.require_name_email,
           moderate_comments: sourceFeedback.moderate_comments,
           show_feedback_to_guests: sourceFeedback.show_feedback_to_guests,
diff --git a/backend/src/routes/adminFeedback.js b/backend/src/routes/adminFeedback.js
index 6519a8a1..74954378 100644
--- a/backend/src/routes/adminFeedback.js
+++ b/backend/src/routes/adminFeedback.js
@@ -233,17 +233,22 @@ router.get('/events/:eventId/feedback-analytics',
         .count('* as count')
         .first();
       
+      // Number() everywhere: Postgres COUNT() comes back as a string, and
+      // string + string in the total_feedback sum concatenates ("00006").
+      const counts = {
+        total_ratings: Number(summaryData.stats?.total_ratings) || 0,
+        total_likes: Number(summaryData.stats?.total_likes) || 0,
+        total_comments: Number(summaryData.stats?.total_comments) || 0,
+        total_favorites: Number(summaryData.stats?.total_favorites) || 0,
+        total_reactions: Number(summaryData.stats?.total_reactions) || 0,
+      };
       const summary = {
         average_rating: parseFloat(avgRatingResult?.average_rating || 0),
-        total_ratings: summaryData.stats?.total_ratings || 0,
-        total_likes: summaryData.stats?.total_likes || 0,
-        total_comments: summaryData.stats?.total_comments || 0,
-        total_favorites: summaryData.stats?.total_favorites || 0,
-        pending_moderation: pendingModeration?.count || 0,
-        total_feedback: (summaryData.stats?.total_ratings || 0) + 
-                       (summaryData.stats?.total_likes || 0) + 
-                       (summaryData.stats?.total_comments || 0) + 
-                       (summaryData.stats?.total_favorites || 0)
+        ...counts,
+        pending_moderation: Number(pendingModeration?.count) || 0,
+        total_feedback: counts.total_ratings + counts.total_likes +
+                       counts.total_comments + counts.total_favorites +
+                       counts.total_reactions
       };
       
       // Get top-rated photos
diff --git a/backend/src/routes/adminGuests.js b/backend/src/routes/adminGuests.js
index 2f24b2f7..7cbb5888 100644
--- a/backend/src/routes/adminGuests.js
+++ b/backend/src/routes/adminGuests.js
@@ -78,6 +78,7 @@ router.get(
           db.raw('COUNT(CASE WHEN photo_feedback.feedback_type = \'favorite\' THEN 1 END) AS favorites'),
           db.raw('COUNT(CASE WHEN photo_feedback.feedback_type = \'comment\' THEN 1 END) AS comments'),
           db.raw('COUNT(CASE WHEN photo_feedback.feedback_type = \'rating\' THEN 1 END) AS ratings'),
+          db.raw('COUNT(CASE WHEN photo_feedback.feedback_type = \'reaction\' THEN 1 END) AS reactions'),
           db.raw('COUNT(DISTINCT photo_feedback.photo_id) AS distinct_photos')
         )
         .orderBy('gallery_guests.created_at', 'desc');
@@ -89,6 +90,7 @@ router.get(
           favorites: parseInt(r.favorites, 10) || 0,
           comments: parseInt(r.comments, 10) || 0,
           ratings: parseInt(r.ratings, 10) || 0,
+          reactions: parseInt(r.reactions, 10) || 0,
           distinct_photos: parseInt(r.distinct_photos, 10) || 0,
         },
       }));
@@ -401,6 +403,7 @@ router.get(
           'photo_feedback.feedback_type',
           'photo_feedback.rating',
           'photo_feedback.comment_text',
+          'photo_feedback.reaction',
           'photo_feedback.created_at',
           'photos.id as photo_id',
           'photos.filename',
@@ -423,6 +426,7 @@ router.get(
         favorited: [],
         rated: [],
         commented: [],
+        reacted: [],
       };
       for (const row of feedback) {
         if (row.feedback_type === 'like') {
@@ -437,6 +441,8 @@ router.get(
             comment: row.comment_text,
             created_at: row.created_at,
           });
+        } else if (row.feedback_type === 'reaction') {
+          selections.reacted.push({ photo: photoFor(row), reaction: row.reaction });
         }
       }
 
@@ -448,6 +454,7 @@ router.get(
             favorites: selections.favorited.length,
             comments: selections.commented.length,
             ratings: selections.rated.length,
+            reactions: selections.reacted.length,
           },
         },
         selections,
diff --git a/backend/src/routes/gallery.js b/backend/src/routes/gallery.js
index 6289909e..59d3771b 100644
--- a/backend/src/routes/gallery.js
+++ b/backend/src/routes/gallery.js
@@ -1956,6 +1956,7 @@ router.get('/:slug/feedback-settings', verifyGalleryAccess, async (req, res) =>
       allow_likes: settings.allow_likes,
       allow_comments: settings.allow_comments,
       allow_favorites: settings.allow_favorites,
+      allow_reactions: settings.allow_reactions,
       show_feedback_to_guests: settings.show_feedback_to_guests,
       require_name_email: settings.require_name_email || false,
       identity_mode: settings.identity_mode || 'simple'
diff --git a/backend/src/routes/galleryFeedback.js b/backend/src/routes/galleryFeedback.js
index 9ca5f00d..f973b13a 100644
--- a/backend/src/routes/galleryFeedback.js
+++ b/backend/src/routes/galleryFeedback.js
@@ -31,6 +31,7 @@ router.get('/:slug/feedback-settings',
         allow_likes: Boolean(settings.allow_likes),
         allow_comments: Boolean(settings.allow_comments),
         allow_favorites: Boolean(settings.allow_favorites),
+        allow_reactions: Boolean(settings.allow_reactions),
         require_name_email: Boolean(settings.require_name_email),
         show_feedback_to_guests: Boolean(settings.show_feedback_to_guests),
         identity_mode: settings.identity_mode || 'simple',
@@ -117,6 +118,9 @@ router.get('/:slug/photos/:photoId/feedback',
             .then(r => r.count),
           like_count: photo.like_count || 0,
           favorite_count: photo.favorite_count || 0,
+          // Gated like the per-emoji map below — aggregate reaction data is
+          // a new surface, kept fully hidden while sharing is off.
+          reaction_count: settings.show_feedback_to_guests ? (photo.reaction_count || 0) : 0,
           comment_count: await db('photo_feedback')
             .where({ 
               photo_id: photoId, 
@@ -128,10 +132,17 @@ router.get('/:slug/photos/:photoId/feedback',
             .first()
             .then(r => r.count)
         },
+        // Per-emoji tallies for the reaction bar (#839). Gated on
+        // show_feedback_to_guests: with sharing off a guest sees only their
+        // own selection (my_feedback.reaction below), no aggregate counts.
+        reactions: settings.show_feedback_to_guests
+          ? await feedbackService.getPhotoReactionCounts(photoId)
+          : {},
         my_feedback: {
           rating: guestFeedback.find(f => f.feedback_type === 'rating')?.rating,
           liked: !!guestFeedback.find(f => f.feedback_type === 'like'),
-          favorited: !!guestFeedback.find(f => f.feedback_type === 'favorite')
+          favorited: !!guestFeedback.find(f => f.feedback_type === 'favorite'),
+          reaction: guestFeedback.find(f => f.feedback_type === 'reaction')?.reaction || null
         }
       });
     } catch (error) {
@@ -181,7 +192,8 @@ router.post('/:slug/photos/:photoId/feedback',
         rating: settings.allow_ratings,
         like: settings.allow_likes,
         comment: settings.allow_comments,
-        favorite: settings.allow_favorites
+        favorite: settings.allow_favorites,
+        reaction: settings.allow_reactions
       };
 
       if (!typeAllowed[feedbackType]) {
@@ -227,6 +239,7 @@ router.post('/:slug/photos/:photoId/feedback',
         feedback_type: feedbackType,
         rating: req.body.rating,
         comment_text: req.body.comment_text,
+        reaction: req.body.reaction,
         guest_name: req.guest?.name ?? req.body.guest_name,
         guest_email: req.guest?.email ?? req.body.guest_email,
         guest_id: req.guest?.id ?? null,
@@ -346,7 +359,8 @@ router.get('/:slug/feedback-summary',
           allow_ratings: settings.allow_ratings,
           allow_likes: settings.allow_likes,
           allow_comments: settings.allow_comments,
-          allow_favorites: settings.allow_favorites
+          allow_favorites: settings.allow_favorites,
+          allow_reactions: settings.allow_reactions
         },
         summary: guestSummary
       });
diff --git a/backend/src/services/feedbackService.js b/backend/src/services/feedbackService.js
index 97bfb43e..5647945b 100644
--- a/backend/src/services/feedbackService.js
+++ b/backend/src/services/feedbackService.js
@@ -1,6 +1,7 @@
 const { db, logActivity } = require('../database/db');
 const logger = require('../utils/logger');
 const { formatBoolean } = require('../utils/dbCompat');
+const { REACTION_EMOJIS } = require('../constants/reactions');
 
 class FeedbackService {
   /**
@@ -21,6 +22,7 @@ class FeedbackService {
           allow_likes: true,
           allow_comments: false,
           allow_favorites: true,
+          allow_reactions: true,
           require_name_email: false,
           moderate_comments: true,
           show_feedback_to_guests: true,
@@ -102,13 +104,19 @@ class FeedbackService {
 
   async submitFeedback(photoId, eventId, feedbackData, guestIdentifier) {
     try {
-      const { feedback_type, rating, comment_text, guest_name, guest_email, ip_address, user_agent, guest_id } = feedbackData;
+      const { feedback_type, rating, comment_text, reaction, guest_name, guest_email, ip_address, user_agent, guest_id } = feedbackData;
 
       // Validate feedback type
-      if (!['rating', 'like', 'comment', 'favorite'].includes(feedback_type)) {
+      if (!['rating', 'like', 'comment', 'favorite', 'reaction'].includes(feedback_type)) {
         throw new Error('Invalid feedback type');
       }
 
+      // Reactions come from a fixed curated set — anything else is rejected
+      // (the route validator enforces this too; this is the last line).
+      if (feedback_type === 'reaction' && !REACTION_EMOJIS.includes(reaction)) {
+        throw new Error('Invalid reaction');
+      }
+
       // Check if similar feedback already exists (prevent duplicates).
       // When a per-person guest_id is present, scope the check to that guest
       // so two guests on the same device can independently like a photo.
@@ -140,6 +148,41 @@ class FeedbackService {
             return { id: existing.id, updated: true };
           }
 
+          // One reaction per guest per photo, changeable (#839): the same
+          // emoji again toggles it off; a different one switches the row.
+          // Toggle/switch act on the full guest-scoped QUERY, not existing.id:
+          // like the sibling like path, the check-then-insert above can race
+          // into duplicate rows — operating on the set makes the next
+          // interaction collapse them instead of leaving a phantom count.
+          const reactionScope = () => {
+            const q = db('photo_feedback').where({
+              photo_id: photoId,
+              event_id: eventId,
+              feedback_type: 'reaction',
+            });
+            if (guest_id) q.where('guest_id', guest_id);
+            else q.where('guest_identifier', guestIdentifier);
+            return q;
+          };
+          if (feedback_type === 'reaction') {
+            if (existing.reaction === reaction) {
+              await reactionScope().delete();
+              await this.updatePhotoFeedbackStats(photoId);
+              return { removed: true };
+            }
+            // Converge to exactly one row: drop any racy duplicates, then
+            // switch the surviving row's emoji.
+            await reactionScope().whereNot('id', existing.id).delete();
+            await db('photo_feedback')
+              .where('id', existing.id)
+              .update({
+                reaction,
+                updated_at: new Date()
+              });
+            await this.updatePhotoFeedbackStats(photoId);
+            return { id: existing.id, updated: true };
+          }
+
           // For likes and favorites, toggle off if already exists.
           // Toggle-off always allowed — the cap below is on adds only, so a
           // guest at the limit can still free a slot by un-favoriting (#655).
@@ -189,6 +232,7 @@ class FeedbackService {
         feedback_type,
         rating: feedback_type === 'rating' ? rating : null,
         comment_text: feedback_type === 'comment' ? comment_text : null,
+        reaction: feedback_type === 'reaction' ? reaction : null,
         guest_name,
         guest_email,
         guest_identifier: guestIdentifier,
@@ -241,7 +285,7 @@ class FeedbackService {
       
       const feedback = await query
         .orderBy('created_at', 'desc')
-        .select('id', 'feedback_type', 'rating', 'comment_text', 'guest_name', 'created_at', 'is_approved', 'is_hidden');
+        .select('id', 'feedback_type', 'rating', 'comment_text', 'reaction', 'guest_name', 'created_at', 'is_approved', 'is_hidden');
       
       return feedback;
     } catch (error) {
@@ -257,7 +301,7 @@ class FeedbackService {
     try {
       const photos = await db('photos')
         .where('event_id', eventId)
-        .select('id', 'filename', 'feedback_count', 'like_count', 'average_rating', 'favorite_count')
+        .select('id', 'filename', 'feedback_count', 'like_count', 'average_rating', 'favorite_count', 'reaction_count')
         .orderBy('average_rating', 'desc')
         .orderBy('like_count', 'desc');
       
@@ -268,7 +312,8 @@ class FeedbackService {
           db.raw('COUNT(CASE WHEN feedback_type = ? THEN 1 END) as total_ratings', ['rating']),
           db.raw('COUNT(CASE WHEN feedback_type = ? THEN 1 END) as total_likes', ['like']),
           db.raw('COUNT(CASE WHEN feedback_type = ? THEN 1 END) as total_comments', ['comment']),
-          db.raw('COUNT(CASE WHEN feedback_type = ? THEN 1 END) as total_favorites', ['favorite'])
+          db.raw('COUNT(CASE WHEN feedback_type = ? THEN 1 END) as total_favorites', ['favorite']),
+          db.raw('COUNT(CASE WHEN feedback_type = ? THEN 1 END) as total_reactions', ['reaction'])
         )
         .first();
       
@@ -282,6 +327,31 @@ class FeedbackService {
     }
   }
 
+  /**
+   * Per-emoji reaction counts for one photo (#839): { '❤️': 3, '👏': 1 }.
+   * Only visible rows count — hidden-by-moderator reactions disappear from
+   * the tallies the same way hidden likes leave like_count.
+   */
+  async getPhotoReactionCounts(photoId) {
+    try {
+      const rows = await db('photo_feedback')
+        .where({ photo_id: photoId, feedback_type: 'reaction' })
+        .where('is_hidden', false)
+        .groupBy('reaction')
+        .select('reaction')
+        .count('id as count');
+
+      const counts = {};
+      for (const row of rows) {
+        if (row.reaction) counts[row.reaction] = Number(row.count) || 0;
+      }
+      return counts;
+    } catch (error) {
+      logger.error('Error getting photo reaction counts:', error);
+      throw error;
+    }
+  }
+
   /**
    * Update photo feedback statistics
    */
@@ -295,11 +365,12 @@ class FeedbackService {
           db.raw('COUNT(CASE WHEN feedback_type = ? AND is_approved = ? THEN 1 END) as comment_count', ['comment', formatBoolean(true)]),
           db.raw('COUNT(CASE WHEN feedback_type = ? THEN 1 END) as like_count', ['like']),
           db.raw('COUNT(CASE WHEN feedback_type = ? THEN 1 END) as favorite_count', ['favorite']),
+          db.raw('COUNT(CASE WHEN feedback_type = ? THEN 1 END) as reaction_count', ['reaction']),
           db.raw('AVG(CASE WHEN feedback_type = ? THEN rating END) as average_rating', ['rating']),
           db.raw('COUNT(DISTINCT COALESCE(CAST(guest_id AS VARCHAR), guest_identifier)) as feedback_count')
         )
         .first();
-      
+
       // Update photo table
       await db('photos')
         .where('id', photoId)
@@ -307,7 +378,8 @@ class FeedbackService {
           feedback_count: stats.feedback_count || 0,
           like_count: stats.like_count || 0,
           average_rating: stats.average_rating || 0,
-          favorite_count: stats.favorite_count || 0
+          favorite_count: stats.favorite_count || 0,
+          reaction_count: stats.reaction_count || 0
         });
     } catch (error) {
       logger.error('Error updating photo feedback stats:', error);
@@ -443,6 +515,7 @@ class FeedbackService {
           'photo_feedback.feedback_type',
           'photo_feedback.rating',
           'photo_feedback.comment_text',
+          'photo_feedback.reaction',
           'photo_feedback.guest_name',
           'photo_feedback.guest_email',
           'photo_feedback.created_at'
@@ -480,6 +553,7 @@ class FeedbackService {
           'photo_feedback.feedback_type',
           'photo_feedback.rating',
           'photo_feedback.comment_text',
+          'photo_feedback.reaction',
           'photo_feedback.guest_name',
           'photo_feedback.guest_email',
           'photo_feedback.guest_identifier',
@@ -505,6 +579,7 @@ class FeedbackService {
             is_liked: false,
             star_rating: '',
             comment: '',
+            reaction: '',
             latest_at: row.created_at,
           };
           byKey.set(key, entry);
@@ -531,6 +606,9 @@ class FeedbackService {
               entry.comment = row.comment_text;
             }
             break;
+          case 'reaction':
+            if (row.reaction) entry.reaction = row.reaction;
+            break;
           default:
             // Unknown feedback type — ignore so a future type doesn't break the export.
             break;
diff --git a/backend/src/utils/feedbackValidation.js b/backend/src/utils/feedbackValidation.js
index eacace87..ac21c3ee 100644
--- a/backend/src/utils/feedbackValidation.js
+++ b/backend/src/utils/feedbackValidation.js
@@ -1,6 +1,7 @@
 const { body, param, validationResult } = require('express-validator');
 const validator = require('validator');
 const { IDENTITY_PRESERVING_NORMALIZE_EMAIL } = require('./emailNormalization');
+const { REACTION_EMOJIS } = require('../constants/reactions');
 
 /**
  * Validation rules for feedback submission
@@ -133,14 +134,20 @@ function getValidationRules(feedbackType) {
  */
 const validateFeedbackSubmission = [
   body('feedback_type')
-    .isIn(['rating', 'like', 'comment', 'favorite'])
+    .isIn(['rating', 'like', 'comment', 'favorite', 'reaction'])
     .withMessage('Invalid feedback type'),
-  
+
   // Conditional validation based on feedback type
   body('rating')
     .if(body('feedback_type').equals('rating'))
     .isInt({ min: 1, max: 5 })
     .withMessage('Rating must be between 1 and 5'),
+
+  // Reactions (#839): fixed curated set only — no free-form emoji.
+  body('reaction')
+    .if(body('feedback_type').equals('reaction'))
+    .custom((value) => REACTION_EMOJIS.includes(value))
+    .withMessage('Invalid reaction'),
   
   body('comment_text')
     .if(body('feedback_type').equals('comment'))
@@ -183,6 +190,7 @@ const validateFeedbackSettings = [
   body('allow_likes').optional().isBoolean(),
   body('allow_comments').optional().isBoolean(),
   body('allow_favorites').optional().isBoolean(),
+  body('allow_reactions').optional().isBoolean(),
   body('require_name_email').optional().isBoolean(),
   body('moderate_comments').optional().isBoolean(),
   body('show_feedback_to_guests').optional().isBoolean(),
diff --git a/frontend/src/components/admin/AdminGuestDetail.tsx b/frontend/src/components/admin/AdminGuestDetail.tsx
index b1a1c60f..58594f3b 100644
--- a/frontend/src/components/admin/AdminGuestDetail.tsx
+++ b/frontend/src/components/admin/AdminGuestDetail.tsx
@@ -1,7 +1,7 @@
 import React, { useState } from 'react';
 import { useQuery } from '@tanstack/react-query';
 import { useTranslation } from 'react-i18next';
-import { X, Heart, Bookmark, Star, MessageCircle } from 'lucide-react';
+import { X, Heart, Bookmark, Star, MessageCircle, Smile } from 'lucide-react';
 import { Loading } from '../common';
 import { guestsService, AdminGuest } from '../../services/guests.service';
 import { AuthenticatedImage } from '../common/AuthenticatedImage';
@@ -14,7 +14,7 @@ interface AdminGuestDetailProps {
   onClose: () => void;
 }
 
-type Tab = 'all' | 'liked' | 'favorited' | 'rated' | 'commented';
+type Tab = 'all' | 'liked' | 'favorited' | 'rated' | 'commented' | 'reacted';
 
 export const AdminGuestDetail: React.FC<AdminGuestDetailProps> = ({ eventId, guest, onClose }) => {
   const { t } = useTranslation();
@@ -31,6 +31,7 @@ export const AdminGuestDetail: React.FC<AdminGuestDetailProps> = ({ eventId, gue
   const favorited = selections?.favorited || [];
   const rated = selections?.rated || [];
   const commented = selections?.commented || [];
+  const reacted = selections?.reacted || [];
 
   // "all" view combines the three visual selection types.
   type GridItem = { photo: { id: number; filename: string; thumbnail_url: string }; badges: string[] };
@@ -48,6 +49,7 @@ export const AdminGuestDetail: React.FC<AdminGuestDetailProps> = ({ eventId, gue
   liked.forEach((p) => add(p, 'like'));
   favorited.forEach((p) => add(p, 'favorite'));
   rated.forEach((r) => add(r.photo, 'rating'));
+  reacted.forEach((r) => add(r.photo, r.reaction));
 
   const visibleItems: GridItem[] =
     tab === 'all'
@@ -58,6 +60,8 @@ export const AdminGuestDetail: React.FC<AdminGuestDetailProps> = ({ eventId, gue
       ? favorited.map((p) => ({ photo: p, badges: ['favorite'] }))
       : tab === 'rated'
       ? rated.map((r) => ({ photo: r.photo, badges: [`${r.rating}★`] }))
+      : tab === 'reacted'
+      ? reacted.map((r) => ({ photo: r.photo, badges: [r.reaction] }))
       : [];
 
   return (
@@ -87,7 +91,7 @@ export const AdminGuestDetail: React.FC<AdminGuestDetailProps> = ({ eventId, gue
         ) : (
           <div className="overflow-y-auto p-4">
             {/* Stats */}
-            <div className="grid grid-cols-4 gap-2 mb-4">
+            <div className="grid grid-cols-5 gap-2 mb-4">
               <div className="p-3 bg-neutral-50 dark:bg-neutral-800 rounded text-center">
                 <div className="text-2xl font-semibold text-neutral-900 dark:text-neutral-100">
                   {liked.length}
@@ -124,11 +128,20 @@ export const AdminGuestDetail: React.FC<AdminGuestDetailProps> = ({ eventId, gue
                   {t('admin.guests.columns.comments', 'Comments')}
                 </div>
               </div>
+              <div className="p-3 bg-neutral-50 dark:bg-neutral-800 rounded text-center">
+                <div className="text-2xl font-semibold text-neutral-900 dark:text-neutral-100">
+                  {reacted.length}
+                </div>
+                <div className="text-xs text-neutral-500 dark:text-neutral-400 flex items-center justify-center gap-1">
+                  <Smile className="w-3 h-3" />
+                  {t('admin.guests.columns.reactions', 'Reactions')}
+                </div>
+              </div>
             </div>
 
             {/* Tabs */}
             <div className="flex gap-1 border-b border-neutral-200 dark:border-neutral-700 mb-4">
-              {(['all', 'liked', 'favorited', 'rated', 'commented'] as const).map((k) => (
+              {(['all', 'liked', 'favorited', 'rated', 'commented', 'reacted'] as const).map((k) => (
                 <button
                   key={k}
                   type="button"
diff --git a/frontend/src/components/admin/AdminGuestsList.tsx b/frontend/src/components/admin/AdminGuestsList.tsx
index d21c1968..01ac46b7 100644
--- a/frontend/src/components/admin/AdminGuestsList.tsx
+++ b/frontend/src/components/admin/AdminGuestsList.tsx
@@ -230,6 +230,9 @@ export const AdminGuestsList: React.FC<AdminGuestsListProps> = ({ eventId, event
                   <th className="px-4 py-3 text-right text-xs font-medium text-neutral-600 dark:text-neutral-400 uppercase">
                     {t('admin.guests.columns.ratings', 'Ratings')}
                   </th>
+                  <th className="px-4 py-3 text-right text-xs font-medium text-neutral-600 dark:text-neutral-400 uppercase">
+                    {t('admin.guests.columns.reactions', 'Reactions')}
+                  </th>
                   <th className="px-4 py-3 text-left text-xs font-medium text-neutral-600 dark:text-neutral-400 uppercase">
                     {t('admin.guests.columns.lastSeen', 'Last seen')}
                   </th>
@@ -270,6 +273,9 @@ export const AdminGuestsList: React.FC<AdminGuestsListProps> = ({ eventId, event
                     <td className="px-4 py-3 text-right text-sm text-neutral-900 dark:text-neutral-100">
                       {guest.stats.ratings}
                     </td>
+                    <td className="px-4 py-3 text-right text-sm text-neutral-900 dark:text-neutral-100">
+                      {guest.stats.reactions}
+                    </td>
                     <td className="px-4 py-3 text-sm text-neutral-600 dark:text-neutral-400">
                       {fmtDate(guest.last_seen_at)}
                     </td>
diff --git a/frontend/src/components/admin/FeedbackSettings.tsx b/frontend/src/components/admin/FeedbackSettings.tsx
index 06a21cbf..1d05c2cf 100644
--- a/frontend/src/components/admin/FeedbackSettings.tsx
+++ b/frontend/src/components/admin/FeedbackSettings.tsx
@@ -1,5 +1,5 @@
 import React from 'react';
-import { MessageSquare, Star, Heart, Bookmark, Shield, Eye, User, Users } from 'lucide-react';
+import { MessageSquare, Star, Heart, Bookmark, Shield, Eye, User, Users, Smile } from 'lucide-react';
 import { Card } from '../common';
 import { useTranslation } from 'react-i18next';
 
@@ -15,6 +15,7 @@ interface FeedbackSettings {
   allow_likes: boolean;
   allow_comments: boolean;
   allow_favorites: boolean;
+  allow_reactions: boolean;
   require_name_email: boolean;
   moderate_comments: boolean;
   show_feedback_to_guests: boolean;
@@ -219,6 +220,24 @@ export const FeedbackSettings: React.FC<FeedbackSettingsProps> = ({
                     </div>
                   </div>
                 </label>
+
+                <label className="flex items-center gap-3 p-3 bg-neutral-50 dark:bg-neutral-800 rounded-lg cursor-pointer hover:bg-neutral-100 dark:hover:bg-neutral-700">
+                  <input
+                    type="checkbox"
+                    checked={settings.allow_reactions}
+                    onChange={() => handleToggle('allow_reactions')}
+                    className="w-4 h-4 text-accent bg-neutral-100 border-neutral-300 rounded focus:ring-primary-500"
+                  />
+                  <Smile className="w-5 h-5 text-neutral-600 dark:text-neutral-400" />
+                  <div className="flex-1">
+                    <div className="text-sm font-medium text-neutral-900 dark:text-neutral-100">
+                      {t('feedback.settings.reactions', 'Emoji Reactions')}
+                    </div>
+                    <div className="text-xs text-neutral-500 dark:text-neutral-400">
+                      {t('feedback.settings.reactionsDesc', 'One emoji per guest per photo (❤️ 😂 😍 👏 🎉)')}
+                    </div>
+                  </div>
+                </label>
               </div>
             </div>
 
diff --git a/frontend/src/components/gallery/GalleryView.tsx b/frontend/src/components/gallery/GalleryView.tsx
index b63eca31..aa4a8d51 100644
--- a/frontend/src/components/gallery/GalleryView.tsx
+++ b/frontend/src/components/gallery/GalleryView.tsx
@@ -721,6 +721,7 @@ export const GalleryView: React.FC<GalleryViewProps> = ({ slug, event }) => {
             allowFavorites: !!feedbackSettings?.allow_favorites,
             allowRatings: !!feedbackSettings?.allow_ratings,
             allowComments: !!feedbackSettings?.allow_comments,
+            allowReactions: !!feedbackSettings?.allow_reactions,
             requireNameEmail: !!feedbackSettings?.require_name_email,
           }}
           isSelectionMode={isSelectionMode}
@@ -967,6 +968,7 @@ export const GalleryView: React.FC<GalleryViewProps> = ({ slug, event }) => {
               allowFavorites: !!feedbackSettings?.allow_favorites,
               allowRatings: !!feedbackSettings?.allow_ratings,
               allowComments: !!feedbackSettings?.allow_comments,
+              allowReactions: !!feedbackSettings?.allow_reactions,
               requireNameEmail: !!feedbackSettings?.require_name_email,
             }}
             isSelectionMode={isSelectionMode}
diff --git a/frontend/src/components/gallery/PhotoFeedback.tsx b/frontend/src/components/gallery/PhotoFeedback.tsx
index 3b74a697..a98ab36b 100644
--- a/frontend/src/components/gallery/PhotoFeedback.tsx
+++ b/frontend/src/components/gallery/PhotoFeedback.tsx
@@ -4,6 +4,7 @@ import { feedbackService } from '../../services/feedback.service';
 import { PhotoRating } from './PhotoRating';
 import { PhotoLikes } from './PhotoLikes';
 import { PhotoFavorites } from './PhotoFavorites';
+import { PhotoReactions } from './PhotoReactions';
 import { PhotoComments } from './PhotoComments';
 import { Skeleton } from '../common';
 
@@ -45,6 +46,8 @@ export const PhotoFeedback: React.FC<PhotoFeedbackProps> = ({
   const [likeCount, setLikeCount] = useState(0);
   const [isFavorited, setIsFavorited] = useState(false);
   const [favoriteCount, setFavoriteCount] = useState(0);
+  const [myReaction, setMyReaction] = useState<string | null>(null);
+  const [reactionCounts, setReactionCounts] = useState<Record<string, number>>({});
 
   // Update local state when data loads
   useEffect(() => {
@@ -54,6 +57,8 @@ export const PhotoFeedback: React.FC<PhotoFeedbackProps> = ({
       setLikeCount(Number(feedbackData.summary.like_count) || 0);
       setIsFavorited(Boolean(feedbackData.my_feedback.favorited));
       setFavoriteCount(Number(feedbackData.summary.favorite_count) || 0);
+      setMyReaction(feedbackData.my_feedback.reaction || null);
+      setReactionCounts(feedbackData.reactions || {});
     }
   }, [feedbackData]);
 
@@ -75,6 +80,18 @@ export const PhotoFeedback: React.FC<PhotoFeedbackProps> = ({
     if (onFeedbackUpdate) onFeedbackUpdate();
   };
 
+  // Optimistic reaction switch: decrement the old emoji, increment the new.
+  const handleReactionChange = (reaction: string | null) => {
+    setReactionCounts(prev => {
+      const next = { ...prev };
+      if (myReaction) next[myReaction] = Math.max(0, (next[myReaction] || 0) - 1);
+      if (reaction) next[reaction] = (next[reaction] || 0) + 1;
+      return next;
+    });
+    setMyReaction(reaction);
+    if (onFeedbackUpdate) onFeedbackUpdate();
+  };
+
   if (settingsLoading) {
     return (
       <div className={`space-y-3 ${className}`}>
@@ -89,7 +106,8 @@ export const PhotoFeedback: React.FC<PhotoFeedbackProps> = ({
   }
 
   const hasAnyFeedbackType = settings.allow_ratings || settings.allow_likes ||
-                            settings.allow_comments || settings.allow_favorites;
+                            settings.allow_comments || settings.allow_favorites ||
+                            settings.allow_reactions;
 
   if (!hasAnyFeedbackType) {
     return null;
@@ -140,6 +158,19 @@ export const PhotoFeedback: React.FC<PhotoFeedbackProps> = ({
         </div>
       )}
 
+      {/* Emoji reactions (#839) */}
+      {settings.allow_reactions && (
+        <PhotoReactions
+          photoId={photoId}
+          gallerySlug={gallerySlug}
+          myReaction={myReaction}
+          reactionCounts={reactionCounts}
+          isEnabled={true}
+          requireNameEmail={settings.require_name_email || false}
+          onReactionChange={handleReactionChange}
+        />
+      )}
+
       {/* Comments Section */}
       {settings.allow_comments && showComments && (
         <div className="border-t pt-4">
diff --git a/frontend/src/components/gallery/PhotoLightbox.tsx b/frontend/src/components/gallery/PhotoLightbox.tsx
index 618541e2..84f0052c 100644
--- a/frontend/src/components/gallery/PhotoLightbox.tsx
+++ b/frontend/src/components/gallery/PhotoLightbox.tsx
@@ -79,6 +79,7 @@ export const PhotoLightbox: React.FC<PhotoLightboxProps> = ({
     allow_likes?: boolean;
     allow_ratings?: boolean;
     allow_comments?: boolean;
+    allow_reactions?: boolean;
     show_feedback_to_guests?: boolean;
     require_name_email?: boolean;
   } | null>(null);
@@ -750,12 +751,11 @@ export const PhotoLightbox: React.FC<PhotoLightboxProps> = ({
               </div>
             )}
             
-            {/* Feedback button with indicator. Gated on allow_comments
-                because likes/ratings already have their own dedicated
-                toolbar buttons above — this MessageSquare button only
-                opens the comments panel, so it has nothing to do when
-                comments are off (#518). */}
-            {feedbackEnabled && feedbackSettings?.allow_comments && (
+            {/* Feedback button with indicator. Likes/ratings have their
+                own dedicated toolbar buttons above, so this panel toggle
+                only has work to do when comments (#518) or the emoji
+                reaction bar (#839) live inside the panel. */}
+            {feedbackEnabled && (feedbackSettings?.allow_comments || feedbackSettings?.allow_reactions) && (
               <button
                 onClick={() => {
                   setShowFeedback(!showFeedback);
diff --git a/frontend/src/components/gallery/PhotoReactions.tsx b/frontend/src/components/gallery/PhotoReactions.tsx
new file mode 100644
index 00000000..37e94748
--- /dev/null
+++ b/frontend/src/components/gallery/PhotoReactions.tsx
@@ -0,0 +1,150 @@
+import React, { useState } from 'react';
+import { useTranslation } from 'react-i18next';
+import { useMutation, useQueryClient } from '@tanstack/react-query';
+import { feedbackService, REACTION_EMOJIS } from '../../services/feedback.service';
+import { toast } from 'react-toastify';
+import { FeedbackIdentityModal } from './FeedbackIdentityModal';
+import { useGuestIdentityOptional } from '../../contexts/GuestIdentityContext';
+
+interface PhotoReactionsProps {
+  photoId: string;
+  gallerySlug: string;
+  /** The guest's current reaction emoji, or null. */
+  myReaction: string | null;
+  /** Per-emoji visible counts, e.g. { '❤️': 3 }. */
+  reactionCounts: Record<string, number>;
+  isEnabled: boolean;
+  requireNameEmail?: boolean;
+  onReactionChange?: (reaction: string | null) => void;
+}
+
+// Emoji reaction bar (#839): one reaction per guest per photo, changeable —
+// tapping the current emoji removes it, tapping another switches. Fixed
+// curated set; identity handling mirrors PhotoLikes (guest-token mode vs.
+// legacy inline name/email prompt).
+export const PhotoReactions: React.FC<PhotoReactionsProps> = ({
+  photoId,
+  gallerySlug,
+  myReaction,
+  reactionCounts,
+  isEnabled,
+  requireNameEmail = false,
+  onReactionChange
+}) => {
+  const { t } = useTranslation();
+  const queryClient = useQueryClient();
+  const guestIdentity = useGuestIdentityOptional();
+  const [isSubmitting, setIsSubmitting] = useState(false);
+  const [showIdentityModal, setShowIdentityModal] = useState(false);
+  const [savedIdentity, setSavedIdentity] = useState<{ name: string; email: string } | null>(null);
+  const [pendingEmoji, setPendingEmoji] = useState<string | null>(null);
+
+  const submitReactionMutation = useMutation({
+    mutationFn: (data: { emoji: string; guest_name?: string; guest_email?: string }) =>
+      feedbackService.submitFeedback(gallerySlug, photoId, {
+        feedback_type: 'reaction',
+        reaction: data.emoji,
+        guest_name: data.guest_name || undefined,
+        guest_email: data.guest_email || undefined
+      }),
+    onMutate: async (data) => {
+      setIsSubmitting(true);
+      // Optimistic update: same emoji toggles off, another switches. The
+      // PRE-mutation value must travel via the mutation context — the
+      // onError closure sees the post-optimistic render, so reading
+      // `myReaction` there would "revert" to the already-wrong state.
+      const previousReaction = myReaction;
+      if (onReactionChange) {
+        onReactionChange(data.emoji === previousReaction ? null : data.emoji);
+      }
+      return { previousReaction };
+    },
+    onSuccess: () => {
+      queryClient.invalidateQueries({ queryKey: ['photo-feedback', gallerySlug, photoId] });
+    },
+    onError: (_error, _data, context) => {
+      if (onReactionChange) {
+        onReactionChange(context?.previousReaction ?? null); // revert optimistic update
+      }
+      toast.error(t('feedback.reactionError', 'Failed to update reaction'));
+    },
+    onSettled: () => {
+      setIsSubmitting(false);
+    }
+  });
+
+  const handleReactionClick = async (emoji: string) => {
+    if (!isEnabled || isSubmitting) return;
+
+    // Guest identity mode: ensure a per-person guest token; the server reads
+    // name/email from the token — body values are ignored.
+    if (guestIdentity?.identityMode === 'guest') {
+      try {
+        await guestIdentity.ensureIdentity();
+      } catch {
+        return; // user cancelled the prompt
+      }
+      submitReactionMutation.mutate({ emoji });
+      return;
+    }
+
+    // Simple mode: legacy inline prompt flow.
+    if (requireNameEmail && !savedIdentity) {
+      setPendingEmoji(emoji);
+      setShowIdentityModal(true);
+    } else {
+      submitReactionMutation.mutate({
+        emoji,
+        ...(savedIdentity ? { guest_name: savedIdentity.name, guest_email: savedIdentity.email } : {})
+      });
+    }
+  };
+
+  const handleIdentitySubmit = (name: string, email: string) => {
+    setSavedIdentity({ name, email });
+    setShowIdentityModal(false);
+    if (pendingEmoji) {
+      submitReactionMutation.mutate({ emoji: pendingEmoji, guest_name: name, guest_email: email });
+      setPendingEmoji(null);
+    }
+  };
+
+  if (!isEnabled) return null;
+
+  return (
+    <>
+      <div className="flex flex-wrap items-center gap-1.5" role="group" aria-label={t('feedback.reactions', 'Reactions')}>
+        {REACTION_EMOJIS.map((emoji) => {
+          const count = reactionCounts[emoji] || 0;
+          const isMine = myReaction === emoji;
+          return (
+            <button
+              key={emoji}
+              type="button"
+              onClick={() => handleReactionClick(emoji)}
+              disabled={isSubmitting}
+              className={`flex items-center gap-1 px-2.5 py-1.5 rounded-full text-sm transition-all ${
+                isMine
+                  ? 'bg-primary-100 dark:bg-primary-900/40 ring-1 ring-primary-500 scale-105'
+                  : 'bg-surface text-muted-theme hover:bg-black/10 hover:scale-105'
+              } ${isSubmitting ? 'cursor-not-allowed opacity-50' : 'cursor-pointer'}`}
+              aria-pressed={isMine}
+              aria-label={isMine
+                ? t('feedback.removeReaction', 'Remove {{emoji}} reaction', { emoji })
+                : t('feedback.reactWith', 'React with {{emoji}}', { emoji })}
+            >
+              <span className="text-base leading-none">{emoji}</span>
+              {count > 0 && <span className="font-medium">{count}</span>}
+            </button>
+          );
+        })}
+      </div>
+      <FeedbackIdentityModal
+        isOpen={showIdentityModal}
+        onClose={() => { setShowIdentityModal(false); setPendingEmoji(null); }}
+        onSubmit={handleIdentitySubmit}
+        feedbackType={t('feedback.reaction', 'reaction')}
+      />
+    </>
+  );
+};
diff --git a/frontend/src/components/gallery/layouts/BaseGalleryLayout.tsx b/frontend/src/components/gallery/layouts/BaseGalleryLayout.tsx
index e0bff52d..c97bf163 100644
--- a/frontend/src/components/gallery/layouts/BaseGalleryLayout.tsx
+++ b/frontend/src/components/gallery/layouts/BaseGalleryLayout.tsx
@@ -29,6 +29,7 @@ export interface BaseGalleryLayoutProps {
     allowFavorites?: boolean;
     allowRatings?: boolean;
     allowComments?: boolean;
+    allowReactions?: boolean;
     requireNameEmail?: boolean;
   };
   // Logout callback for full-page layouts
diff --git a/frontend/src/components/gallery/layouts/GalleryPremiumLayout.css b/frontend/src/components/gallery/layouts/GalleryPremiumLayout.css
index ed95e939..7c24d717 100644
--- a/frontend/src/components/gallery/layouts/GalleryPremiumLayout.css
+++ b/frontend/src/components/gallery/layouts/GalleryPremiumLayout.css
@@ -408,3 +408,17 @@
 .gallery-premium-animate-in {
   animation: galleryPremiumFadeIn 0.4s ease forwards;
 }
+
+/* Emoji reaction bar over the lightbox (#839). Sits above YARL's container
+   (z-index 9999) and clear of the bottom thumbnail strip. */
+.gallery-premium-lightbox-reactions {
+  position: fixed;
+  left: 50%;
+  transform: translateX(-50%);
+  bottom: 122px;
+  z-index: 10000;
+  background: rgba(20, 20, 20, 0.75);
+  border-radius: 9999px;
+  padding: 6px 10px;
+  backdrop-filter: blur(6px);
+}
diff --git a/frontend/src/components/gallery/layouts/GalleryPremiumLayout.tsx b/frontend/src/components/gallery/layouts/GalleryPremiumLayout.tsx
index cebba08f..e6338214 100644
--- a/frontend/src/components/gallery/layouts/GalleryPremiumLayout.tsx
+++ b/frontend/src/components/gallery/layouts/GalleryPremiumLayout.tsx
@@ -1,4 +1,5 @@
 import React, { useEffect, useState, useMemo, useCallback, useRef } from 'react';
+import { createPortal } from 'react-dom';
 import { MasonryPhotoAlbum } from 'react-photo-album';
 import 'react-photo-album/masonry.css';
 import Lightbox from 'yet-another-react-lightbox';
@@ -19,6 +20,7 @@ import type { BaseGalleryLayoutProps } from './BaseGalleryLayout';
 import type { Photo } from '../../../types';
 import { AuthenticatedImage } from '../../common';
 import { feedbackService } from '../../../services/feedback.service';
+import { PhotoReactions } from '../PhotoReactions';
 import { useGuestIdentityOptional } from '../../../contexts/GuestIdentityContext';
 import { FeedbackIdentityModal } from '../FeedbackIdentityModal';
 import { galleryService } from '../../../services/gallery.service';
@@ -208,6 +210,14 @@ export const GalleryPremiumLayout: React.FC<GalleryPremiumLayoutProps> = ({
     likedSeededRef.current = true;
   }, [photos]);
   const [savedIdentity, setSavedIdentity] = useState<{ name: string; email: string } | null>(null);
+  // Emoji reactions (#839) inside the premium lightbox. This layout uses
+  // yet-another-react-lightbox instead of the shared PhotoLightbox, so the
+  // reaction bar is a fixed overlay fed by its own per-photo fetch.
+  const [reactionState, setReactionState] = useState<{
+    photoId: number;
+    mine: string | null;
+    counts: Record<string, number>;
+  } | null>(null);
   const guestIdentity = useGuestIdentityOptional();
   const [showIdentityModal, setShowIdentityModal] = useState(false);
   const [pendingLikePhotoId, setPendingLikePhotoId] = useState<number | null>(null);
@@ -229,6 +239,41 @@ export const GalleryPremiumLayout: React.FC<GalleryPremiumLayoutProps> = ({
     return photos.filter(photo => photo.category_name === activeCategory);
   }, [photos, activeCategory]);
 
+  const currentLightboxPhoto = lightboxIndex >= 0 ? filteredPhotos[lightboxIndex] : null;
+  const reactionsActive = feedbackEnabled && !!feedbackOptions?.allowReactions;
+
+  // Fetch the current photo's reaction tallies + my selection when the
+  // lightbox lands on it. Optimistic updates below keep it fresh in place.
+  useEffect(() => {
+    if (!currentLightboxPhoto || !reactionsActive) {
+      setReactionState(null);
+      return undefined;
+    }
+    let alive = true;
+    feedbackService.getPhotoFeedback(slug, String(currentLightboxPhoto.id))
+      .then((d) => {
+        if (!alive) return;
+        setReactionState({
+          photoId: currentLightboxPhoto.id,
+          mine: d.my_feedback.reaction || null,
+          counts: d.reactions || {},
+        });
+      })
+      .catch(() => { /* bar simply stays hidden for this photo */ });
+    return () => { alive = false; };
+  }, [currentLightboxPhoto?.id, reactionsActive, slug]);
+
+  const handleReactionChange = useCallback((next: string | null) => {
+    setReactionState((prev) => {
+      if (!prev) return prev;
+      const counts = { ...prev.counts };
+      if (prev.mine) counts[prev.mine] = Math.max(0, (counts[prev.mine] || 0) - 1);
+      if (next) counts[next] = (counts[next] || 0) + 1;
+      return { ...prev, mine: next, counts };
+    });
+    onFeedbackChange?.();
+  }, [onFeedbackChange]);
+
   // Get hero photo
   const heroPhoto = heroPhotoOverride || photos[0];
 
@@ -587,6 +632,26 @@ export const GalleryPremiumLayout: React.FC<GalleryPremiumLayoutProps> = ({
         }}
       />
 
+      {/* Emoji reaction bar over the lightbox (#839). Portaled to
+          document.body: inside the layout tree an ancestor stacking context
+          (framer-motion transforms) would paint it UNDER yarl's body-level
+          portal and its backdrop would swallow every click. As a body child
+          the z-index 10000 genuinely beats yarl's 9999. */}
+      {currentLightboxPhoto && reactionsActive && reactionState?.photoId === currentLightboxPhoto.id && createPortal(
+        <div className="gallery-premium-lightbox-reactions">
+          <PhotoReactions
+            photoId={String(currentLightboxPhoto.id)}
+            gallerySlug={slug}
+            myReaction={reactionState.mine}
+            reactionCounts={reactionState.counts}
+            isEnabled={true}
+            requireNameEmail={!!feedbackOptions?.requireNameEmail}
+            onReactionChange={handleReactionChange}
+          />
+        </div>,
+        document.body
+      )}
+
       {/* Identity Modal */}
       <FeedbackIdentityModal
         isOpen={showIdentityModal}
diff --git a/frontend/src/i18n/locales/de.json b/frontend/src/i18n/locales/de.json
index a1bba566..b62ee3d6 100644
--- a/frontend/src/i18n/locales/de.json
+++ b/frontend/src/i18n/locales/de.json
@@ -2728,6 +2728,7 @@
         "favorites": "Favoriten",
         "comments": "Kommentare",
         "ratings": "Bewertungen",
+        "reactions": "Reaktionen",
         "lastSeen": "Zuletzt gesehen"
       },
       "view": "Details anzeigen",
@@ -2741,6 +2742,7 @@
         "liked": "Gemocht",
         "favorited": "Favorisiert",
         "rated": "Bewertet",
+        "reacted": "Reagiert",
         "commented": "Kommentiert"
       },
       "inviteStatus": {
@@ -2796,7 +2798,9 @@
       "event_renamed": "Ereignis umbenannt: {{eventName}}",
       "photo_rating": "Foto bewertet in {{eventName}}",
       "photo_comment": "Foto kommentiert in {{eventName}}",
+      "photo_reaction": "Foto-Reaktion in {{eventName}}",
       "guest_feedback_like": "Gast hat ein Foto geliked in {{eventName}}",
+      "guest_feedback_reaction": "Gast hat auf ein Foto in {{eventName}} reagiert",
       "guest_feedback_favorite": "Gast hat ein Foto als Favorit markiert in {{eventName}}",
       "guest_feedback_rating": "Gast hat ein Foto bewertet in {{eventName}}",
       "guest_feedback_comment": "Gast hat ein Foto kommentiert in {{eventName}}",
@@ -3337,6 +3341,12 @@
     "patternDescription": "Passwörter werden mit Ihrem Veranstaltungsnamen und -datum generiert. Beispiel: \"Location2024$August\" für bessere Sicherheit und Merkbarkeit."
   },
   "feedback": {
+    "reaction": "Reaktion",
+    "reactions": "Reaktionen",
+    "reactWith": "Mit {{emoji}} reagieren",
+    "removeReaction": "{{emoji}}-Reaktion entfernen",
+    "reactionError": "Reaktion konnte nicht aktualisiert werden",
+    "totalReactions": "Reaktionen gesamt",
     "comments": "Kommentare",
     "addComment": "Kommentar hinzufügen",
     "yourName": "Ihr Name",
@@ -3365,6 +3375,8 @@
       "comments": "Kommentare",
       "commentsDesc": "Textkommentare auf Fotos",
       "favorites": "Favoriten",
+      "reactions": "Emoji-Reaktionen",
+      "reactionsDesc": "Ein Emoji pro Gast und Foto (❤️ 😂 😍 👏 🎉)",
       "favoritesDesc": "Fotos als Favoriten markieren",
       "perGuestLimits": "Limits pro Gast",
       "perGuestLimitsDesc": "Begrenzen, wie viele Fotos jeder Gast favorisieren oder liken kann — praktisch für „Wählen Sie Ihre Top-N fürs Album“-Abläufe. 0 = unbegrenzt. Eine Senkung unter den aktuellen Stand eines Gasts lässt vorhandene Einträge bestehen; nur neue Hinzufügungen werden blockiert, bis er welche entfernt.",
@@ -3409,7 +3421,8 @@
       "rating": "Bewertungen",
       "like": "Likes",
       "comment": "Kommentare",
-      "favorite": "Favoriten"
+      "favorite": "Favoriten",
+      "reaction": "Reaktionen"
     },
     "allStatuses": "Alle Status",
     "status": {
diff --git a/frontend/src/i18n/locales/en.json b/frontend/src/i18n/locales/en.json
index 0a7fcf69..6f9d1b1c 100644
--- a/frontend/src/i18n/locales/en.json
+++ b/frontend/src/i18n/locales/en.json
@@ -2306,6 +2306,7 @@
         "favorites": "Favorites",
         "comments": "Comments",
         "ratings": "Ratings",
+        "reactions": "Reactions",
         "lastSeen": "Last seen"
       },
       "view": "View details",
@@ -2319,6 +2320,7 @@
         "liked": "Liked",
         "favorited": "Favorited",
         "rated": "Rated",
+        "reacted": "Reacted",
         "commented": "Commented"
       },
       "inviteStatus": {
@@ -2351,7 +2353,9 @@
       "photo_favorite": "Photo favorited in {{eventName}}",
       "photo_rating": "Photo rated in {{eventName}}",
       "photo_comment": "Photo commented in {{eventName}}",
+      "photo_reaction": "Photo reaction in {{eventName}}",
       "guest_feedback_like": "Guest liked a photo in {{eventName}}",
+      "guest_feedback_reaction": "Guest reacted to a photo in {{eventName}}",
       "guest_feedback_favorite": "Guest favorited a photo in {{eventName}}",
       "guest_feedback_rating": "Guest rated a photo in {{eventName}}",
       "guest_feedback_comment": "Guest commented on a photo in {{eventName}}",
@@ -3358,6 +3362,12 @@
     "patternDescription": "Passwords are generated using your event name and date. Example: \"Venue2024$August\" for better security and memorability."
   },
   "feedback": {
+    "reaction": "reaction",
+    "reactions": "Reactions",
+    "reactWith": "React with {{emoji}}",
+    "removeReaction": "Remove {{emoji}} reaction",
+    "reactionError": "Failed to update reaction",
+    "totalReactions": "Total Reactions",
     "comments": "Comments",
     "addComment": "Add Comment",
     "yourName": "Your name",
@@ -3386,6 +3396,8 @@
       "comments": "Comments",
       "commentsDesc": "Text comments on photos",
       "favorites": "Favorites",
+      "reactions": "Emoji Reactions",
+      "reactionsDesc": "One emoji per guest per photo (❤️ 😂 😍 👏 🎉)",
       "favoritesDesc": "Mark photos as favorites",
       "perGuestLimits": "Per-guest limits",
       "perGuestLimitsDesc": "Cap how many photos each guest can favorite or like — useful for \"pick your top N for the album\" workflows. Leave at 0 for no limit. Lowering a cap below an existing guest's count keeps their existing rows; only new adds are blocked until they remove some.",
@@ -3430,7 +3442,8 @@
       "rating": "Ratings",
       "like": "Likes",
       "comment": "Comments",
-      "favorite": "Favorites"
+      "favorite": "Favorites",
+      "reaction": "Reactions"
     },
     "allStatuses": "All Statuses",
     "status": {
diff --git a/frontend/src/i18n/locales/es.json b/frontend/src/i18n/locales/es.json
index dcf38e6f..c29f0479 100644
--- a/frontend/src/i18n/locales/es.json
+++ b/frontend/src/i18n/locales/es.json
@@ -1492,7 +1492,9 @@
       "photo_favorite": "Foto añadida a favoritos en {{eventName}}",
       "photo_rating": "Foto valorada en {{eventName}}",
       "photo_comment": "Comentario en foto en {{eventName}}",
+      "photo_reaction": "Reacción a una foto en {{eventName}}",
       "guest_feedback_like": "Invitado marcó me gusta en {{eventName}}",
+      "guest_feedback_reaction": "Invitado reaccionó a una foto en {{eventName}}",
       "guest_feedback_favorite": "Invitado añadió a favoritos en {{eventName}}",
       "guest_feedback_rating": "Invitado valoró una foto en {{eventName}}",
       "guest_feedback_comment": "Invitado comentó en una foto en {{eventName}}",
@@ -2348,6 +2350,12 @@
     "patternDescription": "Las contraseñas se generan usando el nombre y la fecha del evento. Ejemplo: \"Venue2024$August\" para mayor seguridad y memorización."
   },
   "feedback": {
+    "reaction": "reacción",
+    "reactions": "Reacciones",
+    "reactWith": "Reaccionar con {{emoji}}",
+    "removeReaction": "Quitar la reacción {{emoji}}",
+    "reactionError": "No se pudo actualizar la reacción",
+    "totalReactions": "Reacciones totales",
     "comments": "Comentarios",
     "addComment": "Añadir comentario",
     "yourName": "Tu nombre",
@@ -2387,6 +2395,8 @@
       "comments": "Comentarios",
       "commentsDesc": "Comentarios de texto en fotos",
       "favorites": "Favoritos",
+      "reactions": "Reacciones con emojis",
+      "reactionsDesc": "Un emoji por invitado y foto (❤️ 😂 😍 👏 🎉)",
       "favoritesDesc": "Marcar fotos como favoritas",
       "identityMode": "Modo de identidad",
       "identityModeSimple": "Feedback simple",
diff --git a/frontend/src/i18n/locales/fr.json b/frontend/src/i18n/locales/fr.json
index d5410eb2..28720ba1 100644
--- a/frontend/src/i18n/locales/fr.json
+++ b/frontend/src/i18n/locales/fr.json
@@ -1699,6 +1699,7 @@
         "favorites": "Favoris",
         "comments": "Commentaires",
         "ratings": "Notes",
+        "reactions": "Réactions",
         "lastSeen": "Dernière visite"
       },
       "view": "Voir les détails",
@@ -1712,6 +1713,7 @@
         "liked": "Aimés",
         "favorited": "Favoris",
         "rated": "Notés",
+        "reacted": "A réagi",
         "commented": "Commentés"
       },
       "inviteStatus": {
@@ -1744,7 +1746,9 @@
       "photo_favorite": "Photo marquée comme favori dans {{eventName}}",
       "photo_rating": "Photo notée dans {{eventName}}",
       "photo_comment": "Commentaire ajouté sur une photo dans {{eventName}}",
+      "photo_reaction": "Réaction à une photo dans {{eventName}}",
       "guest_feedback_like": "Un invité a aimé une photo dans {{eventName}}",
+      "guest_feedback_reaction": "Un invité a réagi à une photo dans {{eventName}}",
       "guest_feedback_favorite": "Un invité a marqué une photo comme favori dans {{eventName}}",
       "guest_feedback_rating": "Un invité a noté une photo dans {{eventName}}",
       "guest_feedback_comment": "Un invité a commenté une photo dans {{eventName}}",
@@ -2496,6 +2500,12 @@
     "patternDescription": "Les mots de passe sont générés à partir du nom de votre événement et de la date. Exemple : \"Lieu2024$Août\" pour une meilleure sécurité et mémorisation."
   },
   "feedback": {
+    "reaction": "réaction",
+    "reactions": "Réactions",
+    "reactWith": "Réagir avec {{emoji}}",
+    "removeReaction": "Retirer la réaction {{emoji}}",
+    "reactionError": "Impossible de mettre à jour la réaction",
+    "totalReactions": "Total des réactions",
     "comments": "Commentaires",
     "addComment": "Ajouter un commentaire",
     "yourName": "Votre nom",
@@ -2524,6 +2534,8 @@
       "comments": "Commentaires",
       "commentsDesc": "Commentaires textuels sur les photos",
       "favorites": "Favoris",
+      "reactions": "Réactions emoji",
+      "reactionsDesc": "Un emoji par invité et par photo (❤️ 😂 😍 👏 🎉)",
       "favoritesDesc": "Marquer les photos comme favoris",
       "identityMode": "Mode d'identité",
       "identityModeSimple": "Commentaires simples",
@@ -2562,7 +2574,8 @@
       "rating": "Notes",
       "like": "J'aimes",
       "comment": "Commentaires",
-      "favorite": "Favoris"
+      "favorite": "Favoris",
+      "reaction": "Réactions"
     },
     "allStatuses": "Tous statuts",
     "status": {
diff --git a/frontend/src/i18n/locales/nl.json b/frontend/src/i18n/locales/nl.json
index 362fba51..94f871d1 100644
--- a/frontend/src/i18n/locales/nl.json
+++ b/frontend/src/i18n/locales/nl.json
@@ -1688,6 +1688,7 @@
         "favorites": "Favorieten",
         "comments": "Opmerkingen",
         "ratings": "Beoordelingen",
+        "reactions": "Reacties",
         "lastSeen": "Laatste bezoek"
       },
       "view": "Details bekijken",
@@ -1701,6 +1702,7 @@
         "liked": "Geliked",
         "favorited": "Favoriet",
         "rated": "Beoordeeld",
+        "reacted": "Gereageerd",
         "commented": "Becommentarieerd"
       },
       "inviteStatus": {
@@ -1756,7 +1758,9 @@
       "event_renamed": "Evenement hernoemd: {{eventName}}",
       "photo_rating": "Foto beoordeeld in {{eventName}}",
       "photo_comment": "Foto becommentarieerd in {{eventName}}",
+      "photo_reaction": "Fotoreactie in {{eventName}}",
       "guest_feedback_like": "Gast heeft een foto geliked in {{eventName}}",
+      "guest_feedback_reaction": "Gast reageerde op een foto in {{eventName}}",
       "guest_feedback_favorite": "Gast heeft een foto als favoriet gemarkeerd in {{eventName}}",
       "guest_feedback_rating": "Gast heeft een foto beoordeeld in {{eventName}}",
       "guest_feedback_comment": "Gast heeft een opmerking geplaatst op een foto in {{eventName}}",
@@ -2485,6 +2489,12 @@
     "patternDescription": "Wachtwoorden worden gegenereerd met uw evenementnaam en datum. Voorbeeld: \"Locatie2024$Augustus\" voor betere beveiliging en herkenbaarheid."
   },
   "feedback": {
+    "reaction": "reactie",
+    "reactions": "Reacties",
+    "reactWith": "Reageer met {{emoji}}",
+    "removeReaction": "{{emoji}}-reactie verwijderen",
+    "reactionError": "Reactie kon niet worden bijgewerkt",
+    "totalReactions": "Totaal reacties",
     "comments": "Opmerkingen",
     "addComment": "Opmerking toevoegen",
     "yourName": "Uw naam",
@@ -2513,6 +2523,8 @@
       "comments": "Opmerkingen",
       "commentsDesc": "Tekstopmerkingen bij foto's",
       "favorites": "Favorieten",
+      "reactions": "Emoji-reacties",
+      "reactionsDesc": "Eén emoji per gast per foto (❤️ 😂 😍 👏 🎉)",
       "favoritesDesc": "Foto's als favoriet markeren",
       "identityMode": "Identiteitsmodus",
       "identityModeSimple": "Eenvoudige feedback",
@@ -2551,7 +2563,8 @@
       "rating": "Beoordelingen",
       "like": "Likes",
       "comment": "Opmerkingen",
-      "favorite": "Favorieten"
+      "favorite": "Favorieten",
+      "reaction": "Reacties"
     },
     "allStatuses": "Alle statussen",
     "status": {
diff --git a/frontend/src/i18n/locales/pt.json b/frontend/src/i18n/locales/pt.json
index 79340692..588647a8 100644
--- a/frontend/src/i18n/locales/pt.json
+++ b/frontend/src/i18n/locales/pt.json
@@ -1713,6 +1713,7 @@
         "favorites": "Favoritos",
         "comments": "Comentários",
         "ratings": "Avaliações",
+        "reactions": "Reações",
         "lastSeen": "Última visita"
       },
       "view": "Ver detalhes",
@@ -1726,6 +1727,7 @@
         "liked": "Gostou",
         "favorited": "Favorito",
         "rated": "Avaliado",
+        "reacted": "Reagiu",
         "commented": "Comentado"
       },
       "inviteStatus": {
@@ -1781,7 +1783,9 @@
       "event_renamed": "Evento renomeado: {{eventName}}",
       "photo_rating": "Foto avaliada em {{eventName}}",
       "photo_comment": "Foto comentada em {{eventName}}",
+      "photo_reaction": "Reação a uma foto em {{eventName}}",
       "guest_feedback_like": "Convidado curtiu uma foto em {{eventName}}",
+      "guest_feedback_reaction": "Convidado reagiu a uma foto em {{eventName}}",
       "guest_feedback_favorite": "Convidado adicionou uma foto aos favoritos em {{eventName}}",
       "guest_feedback_rating": "Convidado avaliou uma foto em {{eventName}}",
       "guest_feedback_comment": "Convidado comentou uma foto em {{eventName}}",
@@ -2510,6 +2514,12 @@
     "patternDescription": "As senhas são geradas usando o nome e data do evento. Ex: \"Evento2024$Agosto\" para melhor memorização."
   },
   "feedback": {
+    "reaction": "reação",
+    "reactions": "Reações",
+    "reactWith": "Reagir com {{emoji}}",
+    "removeReaction": "Remover a reação {{emoji}}",
+    "reactionError": "Não foi possível atualizar a reação",
+    "totalReactions": "Total de reações",
     "comments": "Comentários",
     "addComment": "Adicionar Comentário",
     "yourName": "Seu nome",
@@ -2538,6 +2548,8 @@
       "comments": "Comentários",
       "commentsDesc": "Comentários em texto nas fotos",
       "favorites": "Favoritos",
+      "reactions": "Reações com emojis",
+      "reactionsDesc": "Um emoji por convidado por foto (❤️ 😂 😍 👏 🎉)",
       "favoritesDesc": "Marcar fotos como favoritas",
       "identityMode": "Modo de identidade",
       "identityModeSimple": "Feedback simples",
@@ -2576,7 +2588,8 @@
       "rating": "Avaliações",
       "like": "Gostos",
       "comment": "Comentários",
-      "favorite": "Favoritos"
+      "favorite": "Favoritos",
+      "reaction": "Reações"
     },
     "allStatuses": "Todos os estados",
     "status": {
diff --git a/frontend/src/i18n/locales/ru.json b/frontend/src/i18n/locales/ru.json
index f91e3b9d..d9c68c6f 100644
--- a/frontend/src/i18n/locales/ru.json
+++ b/frontend/src/i18n/locales/ru.json
@@ -1738,6 +1738,7 @@
         "favorites": "Избранное",
         "comments": "Комментарии",
         "ratings": "Оценки",
+        "reactions": "Реакции",
         "lastSeen": "Последний визит"
       },
       "view": "Подробнее",
@@ -1751,6 +1752,7 @@
         "liked": "Понравилось",
         "favorited": "В избранном",
         "rated": "Оценено",
+        "reacted": "Отреагировал",
         "commented": "Прокомментировано"
       },
       "inviteStatus": {
@@ -1806,7 +1808,9 @@
       "event_renamed": "Событие переименовано: {{eventName}}",
       "photo_rating": "Фото оценено в {{eventName}}",
       "photo_comment": "Фото прокомментировано в {{eventName}}",
+      "photo_reaction": "Реакция на фото в {{eventName}}",
       "guest_feedback_like": "Гость поставил лайк фото в {{eventName}}",
+      "guest_feedback_reaction": "Гость отреагировал на фото в {{eventName}}",
       "guest_feedback_favorite": "Гость добавил фото в избранное в {{eventName}}",
       "guest_feedback_rating": "Гость оценил фото в {{eventName}}",
       "guest_feedback_comment": "Гость прокомментировал фото в {{eventName}}",
@@ -2535,6 +2539,12 @@
     "patternDescription": "Пароли генерируются на основе названия и даты события. Пример: «Место2024$Август» для лучшей запоминаемости и безопасности."
   },
   "feedback": {
+    "reaction": "реакция",
+    "reactions": "Реакции",
+    "reactWith": "Отреагировать {{emoji}}",
+    "removeReaction": "Убрать реакцию {{emoji}}",
+    "reactionError": "Не удалось обновить реакцию",
+    "totalReactions": "Всего реакций",
     "comments": "Комментарии",
     "addComment": "Добавить комментарий",
     "yourName": "Ваше имя",
@@ -2563,6 +2573,8 @@
       "comments": "Комментарии",
       "commentsDesc": "Текстовые комментарии к фото",
       "favorites": "Избранное",
+      "reactions": "Эмодзи-реакции",
+      "reactionsDesc": "Один эмодзи на гостя для каждого фото (❤️ 😂 😍 👏 🎉)",
       "favoritesDesc": "Отмечать фото как избранные",
       "identityMode": "Режим идентификации",
       "identityModeSimple": "Простые отзывы",
@@ -2601,7 +2613,8 @@
       "rating": "Оценки",
       "like": "Лайки",
       "comment": "Комментарии",
-      "favorite": "Избранное"
+      "favorite": "Избранное",
+      "reaction": "Реакции"
     },
     "allStatuses": "Все статусы",
     "status": {
diff --git a/frontend/src/i18n/locales/sl.json b/frontend/src/i18n/locales/sl.json
index a2698293..066dab76 100644
--- a/frontend/src/i18n/locales/sl.json
+++ b/frontend/src/i18n/locales/sl.json
@@ -1688,6 +1688,7 @@
         "favorites": "Priljubljene",
         "comments": "Komentarji",
         "ratings": "Ocene",
+        "reactions": "Odzivi",
         "lastSeen": "Nazadnje viden"
       },
       "view": "Ogled podrobnosti",
@@ -1701,6 +1702,7 @@
         "liked": "Všečkano",
         "favorited": "Dodano med priljubljene",
         "rated": "Ocenjeno",
+        "reacted": "Odzval se",
         "commented": "Komentirano"
       },
       "inviteStatus": {
@@ -1733,7 +1735,9 @@
       "photo_favorite": "Fotografija dodana med priljubljene v {{eventName}}",
       "photo_rating": "Fotografija ocenjena v {{eventName}}",
       "photo_comment": "Fotografija komentirana v {{eventName}}",
+      "photo_reaction": "Odziv na fotografijo v {{eventName}}",
       "guest_feedback_like": "Gost je všečkal fotografijo v {{eventName}}",
+      "guest_feedback_reaction": "Gost se je odzval na fotografijo v {{eventName}}",
       "guest_feedback_favorite": "Gost je dodal fotografijo med priljubljene v {{eventName}}",
       "guest_feedback_rating": "Gost je ocenil fotografijo v {{eventName}}",
       "guest_feedback_comment": "Gost je komentiral fotografijo v {{eventName}}",
@@ -2485,6 +2489,12 @@
     "patternDescription": "Gesla se ustvarijo z uporabo imena in datuma dogodka. Primer: »Lokacija2024$Avgust« za boljšo varnost in lažje pomnjenje."
   },
   "feedback": {
+    "reaction": "odziv",
+    "reactions": "Odzivi",
+    "reactWith": "Odzovi se z {{emoji}}",
+    "removeReaction": "Odstrani odziv {{emoji}}",
+    "reactionError": "Odziva ni bilo mogoče posodobiti",
+    "totalReactions": "Skupaj odzivov",
     "comments": "Komentarji",
     "addComment": "Dodaj komentar",
     "yourName": "Vaše ime",
@@ -2513,6 +2523,8 @@
       "comments": "Komentarji",
       "commentsDesc": "Besedilni komentarji na fotografijah",
       "favorites": "Priljubljene",
+      "reactions": "Emoji odzivi",
+      "reactionsDesc": "En emoji na gosta na fotografijo (❤️ 😂 😍 👏 🎉)",
       "favoritesDesc": "Označi fotografije kot priljubljene",
       "identityMode": "Način identitete",
       "identityModeSimple": "Preproste povratne informacije",
@@ -2551,7 +2563,8 @@
       "rating": "Ocene",
       "like": "Všečki",
       "comment": "Komentarji",
-      "favorite": "Priljubljene"
+      "favorite": "Priljubljene",
+      "reaction": "Odzivi"
     },
     "allStatuses": "Vsa stanja",
     "status": {
diff --git a/frontend/src/pages/admin/CreateEventPage.tsx b/frontend/src/pages/admin/CreateEventPage.tsx
index a922e2e7..af9d2fd9 100644
--- a/frontend/src/pages/admin/CreateEventPage.tsx
+++ b/frontend/src/pages/admin/CreateEventPage.tsx
@@ -64,6 +64,7 @@ interface FormData {
     allow_likes: boolean;
     allow_comments: boolean;
     allow_favorites: boolean;
+    allow_reactions: boolean;
     require_name_email: boolean;
     moderate_comments: boolean;
     show_feedback_to_guests: boolean;
@@ -132,6 +133,7 @@ export const CreateEventPage: React.FC = () => {
       allow_likes: true,
       allow_comments: true,
       allow_favorites: true,
+      allow_reactions: true,
       require_name_email: false,
       moderate_comments: true,
       show_feedback_to_guests: true,
@@ -482,6 +484,7 @@ export const CreateEventPage: React.FC = () => {
       allow_likes: feedbackSettings.allow_likes,
       allow_comments: feedbackSettings.allow_comments,
       allow_favorites: feedbackSettings.allow_favorites,
+      allow_reactions: feedbackSettings.allow_reactions,
       require_name_email: feedbackSettings.require_name_email,
       moderate_comments: feedbackSettings.moderate_comments,
       show_feedback_to_guests: feedbackSettings.show_feedback_to_guests,
diff --git a/frontend/src/pages/admin/EventDetailsPage.tsx b/frontend/src/pages/admin/EventDetailsPage.tsx
index ac3fd15a..c661bbfe 100644
--- a/frontend/src/pages/admin/EventDetailsPage.tsx
+++ b/frontend/src/pages/admin/EventDetailsPage.tsx
@@ -45,6 +45,7 @@ export const EventDetailsPage: React.FC = () => {
     allow_likes: true,
     allow_comments: true,
     allow_favorites: true,
+    allow_reactions: true,
     require_name_email: false,
     moderate_comments: true,
     show_feedback_to_guests: true,
diff --git a/frontend/src/pages/admin/EventFeedbackPage.tsx b/frontend/src/pages/admin/EventFeedbackPage.tsx
index 28a57dfc..945b7868 100644
--- a/frontend/src/pages/admin/EventFeedbackPage.tsx
+++ b/frontend/src/pages/admin/EventFeedbackPage.tsx
@@ -6,6 +6,7 @@ import {
   MessageSquare, 
   Star, 
   Heart, 
+  Smile,
   TrendingUp,
   Filter,
   Download,
@@ -249,6 +250,7 @@ export const EventFeedbackPage: React.FC = () => {
                 <option value="like">{t('feedback.types.like', 'Likes')}</option>
                 <option value="comment">{t('feedback.types.comment', 'Comments')}</option>
                 <option value="favorite">{t('feedback.types.favorite', 'Favorites')}</option>
+                <option value="reaction">{t('feedback.types.reaction', 'Reactions')}</option>
               </select>
               <select
                 value={feedbackFilter.status}
@@ -293,6 +295,9 @@ export const EventFeedbackPage: React.FC = () => {
                             {item.feedback_type === 'rating' && <Star className="w-4 h-4 text-yellow-500" />}
                             {item.feedback_type === 'like' && <Heart className="w-4 h-4 text-red-500" />}
                             {item.feedback_type === 'comment' && <MessageSquare className="w-4 h-4 text-blue-500" />}
+                            {item.feedback_type === 'reaction' && item.reaction && (
+                              <span className="text-base leading-none">{item.reaction}</span>
+                            )}
                             <span className="font-medium text-sm">
                               {item.guest_name || t('feedback.anonymous', 'Anonymous')}
                             </span>
@@ -422,7 +427,7 @@ export const EventFeedbackPage: React.FC = () => {
           ) : analytics ? (
             <>
               {/* Summary Stats */}
-              <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-4 gap-4">
+              <div className="grid grid-cols-1 md:grid-cols-2 lg:grid-cols-5 gap-4">
                 <Card>
                   <div className="p-6">
                     <div className="flex items-center gap-3 mb-2">
@@ -448,6 +453,17 @@ export const EventFeedbackPage: React.FC = () => {
                     </div>
                   </div>
                 </Card>
+                <Card>
+                  <div className="p-6">
+                    <div className="flex items-center gap-3 mb-2">
+                      <Smile className="w-8 h-8 text-amber-500" />
+                      <div>
+                        <p className="text-2xl font-bold">{analytics.summary.total_reactions || 0}</p>
+                        <p className="text-sm text-neutral-600">{t('feedback.totalReactions', 'Total Reactions')}</p>
+                      </div>
+                    </div>
+                  </div>
+                </Card>
                 <Card>
                   <div className="p-6">
                     <div className="flex items-center gap-3 mb-2">
diff --git a/frontend/src/services/admin.service.ts b/frontend/src/services/admin.service.ts
index d2dfcfc6..c48098a0 100644
--- a/frontend/src/services/admin.service.ts
+++ b/frontend/src/services/admin.service.ts
@@ -116,10 +116,12 @@ export type ActivityType =
   | "photo_favorite"
   | "photo_rating"
   | "photo_comment"
+  | "photo_reaction"
   | "guest_feedback_like"
   | "guest_feedback_favorite"
   | "guest_feedback_rating"
   | "guest_feedback_comment"
+  | "guest_feedback_reaction"
   | "word_filter_added"
   | "external_import_completed"
   | "bulk_archive_completed"
diff --git a/frontend/src/services/events.service.ts b/frontend/src/services/events.service.ts
index 0ef951c0..0acc02bd 100644
--- a/frontend/src/services/events.service.ts
+++ b/frontend/src/services/events.service.ts
@@ -36,6 +36,7 @@ interface CreateEventData {
   allow_likes?: boolean;
   allow_comments?: boolean;
   allow_favorites?: boolean;
+  allow_reactions?: boolean;
   require_name_email?: boolean;
   moderate_comments?: boolean;
   show_feedback_to_guests?: boolean;
diff --git a/frontend/src/services/feedback.service.ts b/frontend/src/services/feedback.service.ts
index 596541a9..e6c57ecc 100644
--- a/frontend/src/services/feedback.service.ts
+++ b/frontend/src/services/feedback.service.ts
@@ -2,12 +2,18 @@ import { api } from '../config/api';
 
 export type IdentityMode = 'simple' | 'guest';
 
+// Emoji reactions (#839): the fixed curated set. Mirrored in
+// backend/src/constants/reactions.js — update both together.
+export const REACTION_EMOJIS = ['❤️', '😂', '😍', '👏', '🎉'] as const;
+export type ReactionEmoji = (typeof REACTION_EMOJIS)[number];
+
 export interface FeedbackSettings {
   feedback_enabled: boolean;
   allow_ratings: boolean;
   allow_likes: boolean;
   allow_comments: boolean;
   allow_favorites: boolean;
+  allow_reactions: boolean;
   require_name_email: boolean;
   moderate_comments: boolean;
   show_feedback_to_guests: boolean;
@@ -28,10 +34,11 @@ export interface PhotoFeedback {
   id: number;
   photo_id: number;
   event_id: number;
-  feedback_type: 'rating' | 'like' | 'comment' | 'favorite';
+  feedback_type: 'rating' | 'like' | 'comment' | 'favorite' | 'reaction';
   rating?: number;
   comment_text?: string;
   comment?: string;
+  reaction?: string;
   guest_name?: string;
   guest_email?: string;
   is_approved: boolean;
@@ -49,6 +56,7 @@ export interface FeedbackSummary {
   total_ratings: number;
   like_count: number;
   favorite_count: number;
+  reaction_count?: number;
   comment_count: number;
 }
 
@@ -56,11 +64,14 @@ export interface MyFeedback {
   rating?: number;
   liked: boolean;
   favorited: boolean;
+  reaction?: string | null;
 }
 
 export interface FeedbackResponse {
   feedback: PhotoFeedback[];
   summary: FeedbackSummary;
+  /** Per-emoji tallies for the reaction bar (#839), e.g. { '❤️': 3 }. */
+  reactions?: Record<string, number>;
   my_feedback: MyFeedback;
   pagination?: {
     page: number;
@@ -77,6 +88,7 @@ export interface FeedbackAnalytics {
     total_likes: number;
     total_comments: number;
     total_favorites: number;
+    total_reactions?: number;
     pending_moderation: number;
   };
   topRated: Array<{
@@ -198,9 +210,10 @@ class FeedbackService {
   }
 
   async submitFeedback(slug: string, photoId: string, feedback: {
-    feedback_type: 'rating' | 'like' | 'comment' | 'favorite';
+    feedback_type: 'rating' | 'like' | 'comment' | 'favorite' | 'reaction';
     rating?: number;
     comment_text?: string;
+    reaction?: string;
     guest_name?: string;
     guest_email?: string;
   }) {
diff --git a/frontend/src/services/guests.service.ts b/frontend/src/services/guests.service.ts
index f6184870..95451f77 100644
--- a/frontend/src/services/guests.service.ts
+++ b/frontend/src/services/guests.service.ts
@@ -17,6 +17,7 @@ export interface AdminGuestStats {
   favorites: number;
   comments: number;
   ratings: number;
+  reactions: number;
   distinct_photos: number;
 }
 
@@ -45,6 +46,7 @@ export interface AdminGuestSelections {
   favorited: AdminGuestPhoto[];
   rated: Array<{ photo: AdminGuestPhoto; rating: number }>;
   commented: Array<{ photo: AdminGuestPhoto; comment: string; created_at: string }>;
+  reacted: Array<{ photo: AdminGuestPhoto; reaction: string }>;
 }
 
 export interface AdminGuestDetail {