diff --git a/lib/dev.ml b/lib/dev.ml
index 54ef201..b90c70e 100644
--- a/lib/dev.ml
+++ b/lib/dev.ml
@@ -1888,6 +1888,7 @@ let merged_main_source = {c|
 #include <caml/callback.h>
 #include <caml/mlvalues.h>
 #include <pthread.h>
+#include <fcntl.h>
 #include <stdatomic.h>
 #include <stdint.h>
 #include <stdio.h>
@@ -1918,6 +1919,11 @@ static void flan_merged_exit(int32_t status) {
   (void)status;
   fflush(NULL);
   close(1);
+  /* ...and take fd 1 straight back, because POSIX hands out the lowest free
+   * descriptor: leave it open and the compiler thread's next socket or file
+   * becomes this process's stdout, and the next llc inherits it. The EOF is
+   * unaffected — the pipe's write end is genuinely gone. */
+  if (open("/dev/null", O_WRONLY) < 0) { /* nothing useful to do about it */ }
   for (;;) pause();
 }