diff --git a/tools/run.py b/tools/run.py
index 77b6538d41c..8530d422f86 100755
--- a/tools/run.py
+++ b/tools/run.py
@@ -21,6 +21,16 @@ if cmd and cmd[0] == '--redirect-stdout':
   kwargs = dict(stdout=subprocess.PIPE)
   cmd = cmd[2:]
 
+# --- POC harness: run ia32 ELF binaries under qemu-i386 on x64 host. ---
+try:
+  with open(cmd[0], 'rb') as _f:
+    _hdr = _f.read(20)
+  if _hdr[:4] == b'\x7fELF' and _hdr[4] == 1 and _hdr[18] == 3:  # ELFCLASS32, EM_386
+    cmd = ['/tmp/qemu-i386-static', '-L', '/tmp/i386-rt/root'] + cmd
+except (OSError, IndexError):
+  pass
+# -----------------------------------------------------------------------
+
 process = subprocess.Popen(cmd, **kwargs)
 stdout, _ = process.communicate()
 if stdout_file: