diff --git a/autogen.sh b/autogen.sh
index acebc2381a3..3608b2a418c 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -137,6 +137,15 @@ if $do_autoconf; then
 
   if $do_check; then
 
+    if test -n "$NIX_STORE"; then
+       echo "DEBUG:"
+       ls -l /bin/sh
+       /bin/sh --version
+       type command
+       command -v ls
+       set -x
+    fi
+
     echo 'Checking whether you have the necessary tools...
 (Read INSTALL.REPO for more details on building Emacs)'