diff --git a/pkgs/os-specific/bsd/openbsd/pkgs/shutdown.nix b/pkgs/os-specific/bsd/openbsd/pkgs/shutdown.nix
index 15c602455866..7dd7125a8823 100644
--- a/pkgs/os-specific/bsd/openbsd/pkgs/shutdown.nix
+++ b/pkgs/os-specific/bsd/openbsd/pkgs/shutdown.nix
@@ -1,8 +1,17 @@
-{ mkDerivation }:
+{
+  mkDerivation,
+  reboot,
+  wall,
+}:
 mkDerivation {
   path = "sbin/shutdown";
 
-  preBuild = ''
-    sed -i 's/4550/0550/' Makefile
+  postPatch = ''
+    sed -i 's/4550/0550/' $BSDSRCDIR/sbin/shutdown/Makefile
+
+    substituteInPlace $BSDSRCDIR/sbin/shutdown/pathnames.h \
+      --replace-fail /sbin/halt ${reboot}/bin/halt \
+      --replace-fail /sbin/reboot ${reboot}/bin/reboot \
+      --replace-fail /usr/bin/wall ${wall}/bin/wall
   '';
 }