diff --git a/data.c b/data.c
index d0ed7b9..61438b7 100644
--- a/data.c
+++ b/data.c
@@ -1500,6 +1500,50 @@ int actor_get(snac *snac1, const char *actor, xs_dict **data)
 }
 
 
+/** user limiting (announce blocks) **/
+
+int limited(snac *user, const char *id, int cmd)
+/* announce messages from a followed (0: check, 1: limit; 2: unlimit) */
+{
+    int ret = 0;
+    xs *fn = xs_fmt("%s/limited/", user->basedir);
+    mkdirx(fn);
+
+    xs *md5 = xs_md5_hex(id, strlen(id));
+    fn = xs_str_cat(fn, md5);
+
+    switch (cmd) {
+    case 0: /** check **/
+        ret = !!(mtime(fn) > 0.0);
+        break;
+
+    case 1: /** limit **/
+        if (mtime(fn) > 0.0)
+            ret = -1;
+        else {
+            FILE *f;
+
+            if ((f = fopen(fn, "w")) != NULL) {
+                fprintf(f, "%s\n", id);
+                fclose(f);
+            }
+            else
+                ret = -2;
+        }
+        break;
+
+    case 2: /** unlimit **/
+        if (mtime(fn) > 0.0)
+            ret = unlink(fn);
+        else
+            ret = -1;
+        break;
+    }
+
+    return ret;
+}
+
+
 /** static data **/
 
 xs_str *_static_fn(snac *snac, const char *id)
diff --git a/snac.h b/snac.h
index 2b60165..4652827 100644
--- a/snac.h
+++ b/snac.h
@@ -1,7 +1,7 @@
 /* snac - A simple, minimalistic ActivityPub instance */
 /* copyright (c) 2022 - 2023 grunfink et al. / MIT license */
 
-#define VERSION "2.39"
+#define VERSION "2.40-dev"
 
 #define USER_AGENT "snac/" VERSION
 
@@ -132,6 +132,11 @@ int unpin(snac *user, const char *id);
 int is_pinned(snac *user, const char *id);
 xs_list *pinned_list(snac *user);
 
+int limited(snac *user, const char *id, int cmd);
+#define is_limited(user, id) limited((user), (id), 0)
+#define limit(user, id) limited((user), (id), 1)
+#define unlimit(user, id) limited((user), (id), 2)
+
 void hide(snac *snac, const char *id);
 int is_hidden(snac *snac, const char *id);