diff --git a/photon/libc/sys/horizon/launch.c b/photon/libc/sys/horizon/launch.c
index ae24786..2b2e6e6 100644
--- a/photon/libc/sys/horizon/launch.c
+++ b/photon/libc/sys/horizon/launch.c
@@ -78,6 +78,10 @@ struct cleanup {
     size_t inherited_ns_len;
 
     int *fd;
+
+    /* this is used to send STDIO handles to the interpreter.
+     * the same handles are sent in both messages. */
+    mx_handle_t stdio[LAUNCH_MAX_FDS];
 };
 
 static void set_error_msg(const char *s, ...)
@@ -366,6 +370,7 @@ static int collect_handles(const struct launch_info *info, struct cleanup *clean
         b_idx++;
 
         cleanup->auto_handles[auto_idx++] = fd_handle;
+        cleanup->stdio[i] = fd_handle;
     }
 
     if (info->flags & LAUNCH_INHERIT_NS) {
@@ -1034,6 +1039,9 @@ static int send_interp_bootstrap_message(const struct launch_info *args, struct
         ARG_HANDLE(cleanup->exec.remote_exec_vmar, MX_B_HND(MX_B_VMAR_EXEC,    0)),
         ARG_HANDLE(vdso_vmo,                       MX_B_HND(MX_B_VMO_VDSO,     0)),
         ARG_HANDLE(ldsvc,                          MX_B_HND(MX_B_TUNNEL_LDSVC, cleanup->ldsvc_version)),
+        ARG_HANDLE(cleanup->stdio[0],              MX_B_HND(MX_B_FD,           0)),
+        ARG_HANDLE(cleanup->stdio[1],              MX_B_HND(MX_B_FD,           1)),
+        ARG_HANDLE(cleanup->stdio[2],              MX_B_HND(MX_B_FD,           2)),
     };
 
     static size_t handle_count = sizeof handles / sizeof handles[0];