diff --git a/mxqd.c b/mxqd.c
index 880059f3..ec6b6579 100644
--- a/mxqd.c
+++ b/mxqd.c
@@ -1146,6 +1146,8 @@ static void exec_reaper(struct mxq_server *server,struct mxq_group_list *glist,
                 argv[0]);
 }
 
+static char tmpdir_script[] = LIBEXECDIR "/mxq/tmpdir-setup";
+
 static unsigned long start_job(struct mxq_group_list *glist)
 {
     struct mxq_server *server;
@@ -1158,8 +1160,6 @@ static unsigned long start_job(struct mxq_group_list *glist)
 
     struct mxq_daemon *daemon;
 
-    static char tmpdir_script[] = LIBEXECDIR "/mxq/tmpdir-setup";
-
     pid_t pid;
     int res;
 
@@ -1871,31 +1871,17 @@ static void rename_outfiles(struct mxq_server *server, struct mxq_group *group,
     }
 }
 
-static char *job_tmpdir_path(unsigned long job_id) {
-    char *pathname;
-    pathname = mx_asprintf_forever("%s/%lu", MXQ_JOB_TMPDIR_MNTDIR, job_id);
-    return pathname;
-}
-
-static int unmount_and_remove(char *pathname) {
-    int res;
-    res = rmdir(pathname);
-    if (res && errno==EBUSY) {
-        res = umount(pathname);
-        if (res == 0) {
-            res = rmdir(pathname);
-        }
-    }
-    return res;
-}
-
 static void unmount_job_tmpdir(unsigned long job_id) {
-    char *pathname;
-    pathname=job_tmpdir_path(job_id);
-    if (unmount_and_remove(pathname)) {
-        mx_log_warning("failed to unmount/remove stale job tmpdir %s: %m", pathname);
-    }
-    free(pathname);
+    char *argv[] = {
+        tmpdir_script,
+        "cleanup",
+        mx_asprintf_forever("%lu", job_id),
+        NULL
+    };
+    int res = mx_call_external(tmpdir_script, argv);
+    free(argv[2]);
+    if (res == -1)
+        mx_log_err("cleanup job tmpdir: %m");
 }
 
 static void release_gpu(struct mxq_server *server, struct mxq_group *group, struct mxq_job *job) {