diff --git a/activitypub.c b/activitypub.c
index a259a25..663fa24 100644
--- a/activitypub.c
+++ b/activitypub.c
@@ -117,22 +117,8 @@ int actor_request(snac *snac, char *actor, d_char **data)
         }
     }
 
-#if 0
-    if (valid_status(status) && data && *data) {
-        xs *fn = xs_fmt("%s/inboxes.lst", srv_basedir);
-        FILE *f;
-
-        if ((f = fopen(fn, "a")) != NULL) {
-            char *v;
-            if (!xs_is_null(v = xs_dict_get(*data, "endpoints")) &&
-                !xs_is_null(v = xs_dict_get(v, "sharedInbox"))) {
-                fprintf(f, "%s\n", v);
-            }
-
-            fclose(f);
-        }
-    }
-#endif
+    if (valid_status(status) && data && *data)
+        inbox_add_by_actor(*data);
 
     return status;
 }
diff --git a/data.c b/data.c
index 8934f31..208c057 100644
--- a/data.c
+++ b/data.c
@@ -96,6 +96,9 @@ int srv_open(char *basedir, int auto_upgrade)
     xs *qdir = xs_fmt("%s/queue", srv_basedir);
     mkdirx(qdir);
 
+    xs *ibdir = xs_fmt("%s/inboxes", srv_basedir);
+    mkdirx(ibdir);
+
 #ifdef __OpenBSD__
     char *v = xs_dict_get(srv_config, "disable_openbsd_security");
 
@@ -1363,6 +1366,37 @@ d_char *history_list(snac *snac)
 }
 
 
+/** inbox collection **/
+
+void inbox_add(const char *inbox)
+/* collects a shared inbox */
+{
+    xs *md5 = xs_md5_hex(inbox, strlen(inbox));
+    xs *fn  = xs_fmt("%s/inboxes/%s", srv_basedir, md5);
+    FILE *f;
+
+    if ((f = fopen(fn, "w")) != NULL) {
+        pthread_mutex_lock(&data_mutex);
+
+        fprintf(f, "%s\n", inbox);
+        fclose(f);
+
+        pthread_mutex_unlock(&data_mutex);
+    }
+}
+
+
+void inbox_add_by_actor(const xs_dict *actor)
+/* collects an actor's shared inbox, if it has one */
+{
+    char *v;
+
+    if (!xs_is_null(v = xs_dict_get(actor, "endpoints")) &&
+        !xs_is_null(v = xs_dict_get(v, "sharedInbox")))
+        inbox_add(v);
+}
+
+
 /** the queue **/
 
 static xs_dict *_enqueue_put(const char *fn, xs_dict *msg)
diff --git a/snac.h b/snac.h
index bc929df..9cca864 100644
--- a/snac.h
+++ b/snac.h
@@ -132,6 +132,9 @@ d_char *history_get(snac *snac, char *id);
 int history_del(snac *snac, char *id);
 d_char *history_list(snac *snac);
 
+void inbox_add(const char *inbox);
+void inbox_add_by_actor(const xs_dict *actor);
+
 void enqueue_input(snac *snac, xs_dict *msg, xs_dict *req, int retries);
 void enqueue_output_raw(const char *keyid, const char *seckey,
                         xs_dict *msg, xs_str *inbox, int retries);
diff --git a/utils.c b/utils.c
index 384fde9..cdfa2e6 100644
--- a/utils.c
+++ b/utils.c
@@ -157,6 +157,9 @@ int snac_init(const char *basedir)
     xs *qdir = xs_fmt("%s/queue", srv_basedir);
     mkdirx(qdir);
 
+    xs *ibdir = xs_fmt("%s/inbox", srv_basedir);
+    mkdirx(ibdir);
+
     xs *gfn = xs_fmt("%s/greeting.html", srv_basedir);
     if ((f = fopen(gfn, "w")) == NULL) {
         printf("ERROR: cannot create '%s'\n", gfn);