diff --git a/src/backend/src/filesystem/definitions/capabilities.js b/src/backend/src/filesystem/definitions/capabilities.js
index 95e0424d0..ef9b289d0 100644
--- a/src/backend/src/filesystem/definitions/capabilities.js
+++ b/src/backend/src/filesystem/definitions/capabilities.js
@@ -23,6 +23,7 @@ const capabilityNames = [
     'uuid',
     'operation-trace',
     'readdir-uuid-mode',
+    'update-thumbnail',
 
     // Standard Capabilities
     'read',
diff --git a/src/backend/src/modules/puterfs/lib/PuterFSProvider.js b/src/backend/src/modules/puterfs/lib/PuterFSProvider.js
index 2e3f7c553..3da11f3e5 100644
--- a/src/backend/src/modules/puterfs/lib/PuterFSProvider.js
+++ b/src/backend/src/modules/puterfs/lib/PuterFSProvider.js
@@ -64,6 +64,7 @@ class PuterFSProvider extends putility.AdvancedBase {
     get_capabilities() {
         return new Set([
             fsCapabilities.THUMBNAIL,
+            fsCapabilities.UPDATE_THUMBNAIL,
             fsCapabilities.UUID,
             fsCapabilities.OPERATION_TRACE,
             fsCapabilities.READDIR_UUID_MODE,
@@ -564,6 +565,40 @@ class PuterFSProvider extends putility.AdvancedBase {
             await lock_handle.unlock();
         }
     }
+    
+    async update_thumbnail({ context, node, thumbnail }) {
+        const {
+            actor: inputActor,
+        } = context.values;
+        const actor = inputActor ?? Context.get('actor');
+        
+        context = context ?? Context.get();
+        const services = context.get('services');
+
+        const svc_fsEntry = services.get('fsEntryService');
+        const svc_event = services.get('event');
+
+        const svc_acl = services.get('acl');
+        if ( ! await svc_acl.check(actor, node, 'write') ) {
+            throw await svc_acl.get_safe_acl_error(actor, node, 'write');
+        }
+
+        const uid = await node.get('uid');
+
+        const entryOp = await svc_fsEntry.update(uid, {
+            thumbnail
+        });
+
+        (async () => {
+            await entryOp.awaitDone();
+            svc_event.emit('fs.write.file', {
+                node,
+                context,
+            });
+        })();
+
+        return node;
+    }
 
     /**
      * Write a new file to the filesystem. Throws an error if the destination
diff --git a/src/backend/src/routers/filesystem_api/update.js b/src/backend/src/routers/filesystem_api/update.js
new file mode 100644
index 000000000..7eac77de5
--- /dev/null
+++ b/src/backend/src/routers/filesystem_api/update.js
@@ -0,0 +1,46 @@
+const APIError = require("../../api/APIError");
+const eggspress = require("../../api/eggspress");
+const FSNodeParam = require("../../api/filesystem/FSNodeParam");
+const StringParam = require("../../api/filesystem/StringParam");
+const { is_valid_url } = require("../../helpers");
+const { PuterFSProvider } = require("../../modules/puterfs/lib/PuterFSProvider");
+const { Context } = require("../../util/context");
+
+module.exports = eggspress('/update-fsentry-thumbnail', {
+    subdomain: 'api',
+    verified: true,
+    auth2: true,
+    fs: true,
+    json: true,
+    allowedMethods: ['POST'],
+    parameters: {
+        fsNode: new FSNodeParam('path'),
+        thumbnail: new StringParam('thumbnail'),
+    },
+}, async (req, res, next) => {
+    if ( ! is_valid_url(req.values.thumbnail) ) {
+        throw new APIError.create('field_invalid', null, {
+            key: 'thumbnail',
+            expected: 'a valid URL',
+            got: typeof req.values.thumbnail,
+        });
+    }
+    
+    if ( ! await req.values.fsNode.exists() ) {
+        throw new APIError.create('subject_does_not_exist');
+    }
+    
+    const svc = Context.get('services');
+    
+    const svc_mountpoint = svc.get('mountpoint');
+    const provider =
+        await svc_mountpoint.get_provider(req.values.fsNode.selector);
+        
+    provider.update_thumbnail({
+        context: Context.get(),
+        node: req.values.fsNode,
+        thumbnail: req.body.thumbnail,
+    });
+    
+    res.json({});
+});
diff --git a/src/backend/src/services/FilesystemAPIService.js b/src/backend/src/services/FilesystemAPIService.js
index 9e097b7ba..56cb3644b 100644
--- a/src/backend/src/services/FilesystemAPIService.js
+++ b/src/backend/src/services/FilesystemAPIService.js
@@ -62,6 +62,9 @@ class FilesystemAPIService extends BaseService {
         
         app.use(require('../routers/filesystem_api/search'))
         
+        // temporary or alpha
+        app.use(require('../routers/filesystem_api/update'))
+        
         // v1
         app.use(require('../routers/writeFile'))
         app.use(require('../routers/file'))