diff --git a/DysonNetwork.Shared/Models/ActivityHeatmap.cs b/DysonNetwork.Shared/Models/ActivityHeatmap.cs
new file mode 100644
index 0000000..b5aa8fb
--- /dev/null
+++ b/DysonNetwork.Shared/Models/ActivityHeatmap.cs
@@ -0,0 +1,19 @@
+using NodaTime;
+
+namespace DysonNetwork.Shared.Models;
+
+public class ActivityHeatmap
+{
+    public string Unit { get; set; } = "posts";
+
+    public Instant PeriodStart { get; set; }
+    public Instant PeriodEnd { get; set; }
+
+    public List<ActivityHeatmapItem> Items { get; set; } = new();
+}
+
+public class ActivityHeatmapItem
+{
+    public Instant Date { get; set; }
+    public int Count { get; set; }
+}
\ No newline at end of file
diff --git a/DysonNetwork.Sphere/Publisher/PublisherController.cs b/DysonNetwork.Sphere/Publisher/PublisherController.cs
index d4cb862..0ec75fc 100644
--- a/DysonNetwork.Sphere/Publisher/PublisherController.cs
+++ b/DysonNetwork.Sphere/Publisher/PublisherController.cs
@@ -37,6 +37,14 @@ public class PublisherController(
 
         return Ok(publisher);
     }
+    
+    [HttpGet("{name}/heatmap")]
+    public async Task<ActionResult<ActivityHeatmap>> GetPublisherHeatmap(string name)
+    {
+        var heatmap = await ps.GetPublisherHeatmap(name);
+        if (heatmap is null) return NotFound();
+        return Ok(heatmap);
+    }
 
     [HttpGet("{name}/stats")]
     public async Task<ActionResult<PublisherService.PublisherStats>> GetPublisherStats(string name)
@@ -693,4 +701,4 @@ public class PublisherController(
 
         return NoContent();
     }
-}
\ No newline at end of file
+}
diff --git a/DysonNetwork.Sphere/Publisher/PublisherService.cs b/DysonNetwork.Sphere/Publisher/PublisherService.cs
index f52ccfe..092889b 100644
--- a/DysonNetwork.Sphere/Publisher/PublisherService.cs
+++ b/DysonNetwork.Sphere/Publisher/PublisherService.cs
@@ -283,6 +283,7 @@ public class PublisherService(
     }
 
     private const string PublisherStatsCacheKey = "PublisherStats_{0}";
+    private const string PublisherHeatmapCacheKey = "PublisherHeatmap_{0}";
     private const string PublisherFeatureCacheKey = "PublisherFeature_{0}_{1}";
 
     public async Task<PublisherStats?> GetPublisherStats(string name)
@@ -325,6 +326,45 @@ public class PublisherService(
         return stats;
     }
 
+    public async Task<ActivityHeatmap?> GetPublisherHeatmap(string name)
+    {
+        var cacheKey = string.Format(PublisherHeatmapCacheKey, name);
+        var heatmap = await cache.GetAsync<ActivityHeatmap>(cacheKey);
+        if (heatmap is not null)
+            return heatmap;
+
+        var publisher = await db.Publishers.FirstOrDefaultAsync(e => e.Name == name);
+        if (publisher is null) return null;
+
+        var now = SystemClock.Instance.GetCurrentInstant();
+        var periodStart = now.Minus(Duration.FromDays(365));
+        var periodEnd = now;
+
+        var postGroups = await db.Posts
+            .Where(p => p.PublisherId == publisher.Id && p.CreatedAt >= periodStart && p.CreatedAt <= periodEnd)
+            .Select(p => p.CreatedAt.InUtc().Date)
+            .GroupBy(d => d)
+            .Select(g => new { Date = g.Key, Count = g.Count() })
+            .ToListAsync();
+
+        var items = postGroups.Select(p => new ActivityHeatmapItem
+        {
+            Date = p.Date.AtStartOfDayInZone(DateTimeZone.Utc).ToInstant(),
+            Count = p.Count
+        }).ToList();
+
+        heatmap = new ActivityHeatmap
+        {
+            Unit = "posts",
+            PeriodStart = periodStart,
+            PeriodEnd = periodEnd,
+            Items = items.OrderBy(i => i.Date).ToList()
+        };
+
+        await cache.SetAsync(cacheKey, heatmap, TimeSpan.FromMinutes(5));
+        return heatmap;
+    }
+
     public async Task SetFeatureFlag(Guid publisherId, string flag)
     {
         var featureFlag = await db.PublisherFeatures
@@ -397,4 +437,4 @@ public class PublisherService(
             return m;
         })];
     }
-}
\ No newline at end of file
+}