diff --git a/mxqd.c b/mxqd.c
index bd0fbb0b..16d3f814 100644
--- a/mxqd.c
+++ b/mxqd.c
@@ -983,7 +983,7 @@ static int init_child_process(struct mxq_group_list *glist, struct mxq_job *job)
         return 0;
     }
 
-    res = setreuid(group->user_uid, group->user_uid);
+    res = setreuid(-1, group->user_uid);
     if (res == -1) {
         mx_log_err("job=%s(%d):%lu:%lu setreuid(%d, %d) failed: %m",
             group->user_name, group->user_uid, group->group_id, job->job_id,
@@ -1098,7 +1098,7 @@ static int mxq_redirect_input(char *stdin_fname)
     return 1;
 }
 
-static int user_process(struct mxq_group_list *glist, struct mxq_job *job)
+static int user_process(struct mxq_server *server, struct mxq_group_list *glist, struct mxq_job *job)
 {
     int res;
     char **argv;
@@ -1146,7 +1146,30 @@ static int user_process(struct mxq_group_list *glist, struct mxq_job *job)
         return -errno;
     }
 
-    res = execvp(argv[0], argv);
+    int argc = 0;
+    while (argv[argc] != NULL)
+        argc++;
+
+    char **new_argv = mx_calloc_forever(argc+4+1, sizeof(char *));
+    new_argv[0] = LIBEXECDIR "/mxq/mxq_reaper";
+    new_argv[1] = mx_asprintf_forever("%d", group->user_uid);
+    new_argv[2] = mx_asprintf_forever("%s/%lu.stat", server->finished_jobsdir, job->job_id);
+    new_argv[3] = "--";
+    for (int i = 0; i < argc ; i++)
+        new_argv[i+4] = argv[i];
+    new_argv[argc+4] = NULL;
+
+    res = setuid(0);
+    if (res == -1) {
+        mx_log_err("job=%s(%d):%lu:%lu setuid(0) failed: %m",
+                    group->user_name,
+                    group->user_uid,
+                    group->group_id,
+                    job->job_id);
+        return -errno;
+    }
+
+    res = execvp(new_argv[0], new_argv);
     mx_log_err("job=%s(%d):%lu:%lu execvp(\"%s\", ...): %m",
                 group->user_name,
                 group->user_uid,
@@ -1169,16 +1192,6 @@ static int is_reaper(pid_t pid) {
 }
 
 static int reaper_process(struct mxq_server *server,struct mxq_group_list *glist, struct mxq_job *job) {
-    pid_t pid;
-    struct rusage rusage;
-    int status = 0;
-    pid_t  waited_pid;
-    int    waited_status;
-    struct timeval now;
-    struct timeval realtime;
-    _mx_cleanup_free_ char *finished_job_filename=NULL;
-    _mx_cleanup_free_ char *finished_job_tmpfilename=NULL;
-    FILE *out;
     int res;
 
     struct mxq_group *group;
@@ -1203,85 +1216,9 @@ static int reaper_process(struct mxq_server *server,struct mxq_group_list *glist
         return res;
     }
 
-    pid = fork();
-    if (pid < 0) {
-        mx_log_err("fork: %m");
-        return pid;
-    } else if (pid == 0) {
-        mx_log_debug("starting user process.");
-        res = user_process(glist, job);
-        _exit(EX__MAX+1);
-    }
-    gettimeofday(&job->stats_starttime, NULL);
-
-    while (1) {
-        waited_pid = wait(&waited_status);
-        if (waited_pid < 0) {
-            if (errno==ECHILD) {
-                break;
-            } else {
-                mx_log_warning("reaper: wait: %m");
-                sleep(1);
-            }
-        }
-        if (waited_pid == pid) {
-            status = waited_status;
-        }
-    }
-    gettimeofday(&now, NULL);
-    timersub(&now, &job->stats_starttime, &realtime);
-
-    if (realtime.tv_sec<30) {
-        int wait=30-realtime.tv_sec;
-        mx_log_warning("user process finished to fast (%ld seconds) : delaying termination for %d seconds",realtime.tv_sec,wait);
-        sleep(wait);
-    }
-
-    res = getrusage(RUSAGE_CHILDREN, &rusage);
-    if (res < 0) {
-        mx_log_err("reaper: getrusage: %m");
-        return(res);
-    }
-
-    finished_job_filename = mx_asprintf_forever("%s/%lu.stat", server->finished_jobsdir, job->job_id);
-    finished_job_tmpfilename = mx_asprintf_forever("%s.tmp", finished_job_filename);
-
-    out=fopen(finished_job_tmpfilename,"w");
-    if (!out) {
-        mx_log_fatal("%s: %m",finished_job_tmpfilename);
-        return (-errno);
-    }
-
-    fprintf(out,"1 %d %d %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld %ld\n",
-        getpid(),
-        status,
-        realtime.tv_sec,realtime.tv_usec,
-        rusage.ru_utime.tv_sec,rusage.ru_utime.tv_usec,
-        rusage.ru_stime.tv_sec,rusage.ru_stime.tv_usec,
-        rusage.ru_maxrss,
-        rusage.ru_ixrss,
-        rusage.ru_idrss,
-        rusage.ru_isrss,
-        rusage.ru_minflt,
-        rusage.ru_majflt,
-        rusage.ru_nswap,
-        rusage.ru_inblock,
-        rusage.ru_oublock,
-        rusage.ru_msgsnd,
-        rusage.ru_msgrcv,
-        rusage.ru_nsignals,
-        rusage.ru_nvcsw,
-        rusage.ru_nivcsw
-    );
-    fflush(out);
-    fsync(fileno(out));
-    fclose(out);
-    res=rename(finished_job_tmpfilename,finished_job_filename);
-    if (res<0)  {
-        mx_log_fatal("rename %s: %m",finished_job_tmpfilename);
-        return(res);
-    }
-    return(0);
+    res = user_process(server, glist, job);
+    mx_log_err("user process:: %m");
+    return res;
 }
 
 static unsigned long start_job(struct mxq_group_list *glist)