diff --git a/pkgs/by-name/at/at/package.nix b/pkgs/by-name/at/at/package.nix
index cd1a7ea6dfcb..7c5014ad90e6 100644
--- a/pkgs/by-name/at/at/package.nix
+++ b/pkgs/by-name/at/at/package.nix
@@ -32,17 +32,16 @@ stdenv.mkDerivation (finalAttrs: {
   postPatch = ''
     # Remove chown commands and setuid bit
     substituteInPlace Makefile.in \
-      --replace ' -o root ' ' ' \
-      --replace ' -g root ' ' ' \
-      --replace ' -o $(DAEMON_USERNAME) ' ' ' \
-      --replace ' -o $(DAEMON_GROUPNAME) ' ' ' \
-      --replace ' -g $(DAEMON_GROUPNAME) ' ' ' \
-      --replace '$(DESTDIR)$(etcdir)' "$out/etc" \
-      --replace '$(DESTDIR)$(ATJOB_DIR)' "$out/var/spool/atjobs" \
-      --replace '$(DESTDIR)$(ATSPOOL_DIR)' "$out/var/spool/atspool" \
-      --replace '$(DESTDIR)$(LFILE)' "$out/var/spool/atjobs/.SEQ" \
-      --replace 'chown' '# skip chown' \
-      --replace '6755' '0755'
+      --replace-fail ' -o root ' ' ' \
+      --replace-fail ' -g root ' ' ' \
+      --replace-fail ' -o $(DAEMON_USERNAME) ' ' ' \
+      --replace-fail ' -g $(DAEMON_GROUPNAME) ' ' ' \
+      --replace-fail '$(DESTDIR)$(etcdir)' "$out/etc" \
+      --replace-fail '$(DESTDIR)$(ATJOB_DIR)' "$out/var/spool/atjobs" \
+      --replace-fail '$(DESTDIR)$(ATSPOOL_DIR)' "$out/var/spool/atspool" \
+      --replace-fail '$(DESTDIR)$(LFILE)' "$out/var/spool/atjobs/.SEQ" \
+      --replace-fail 'chown' '# skip chown' \
+      --replace-fail '6755' '0755'
   '';
 
   nativeBuildInputs = [
@@ -57,7 +56,7 @@ stdenv.mkDerivation (finalAttrs: {
     export SENDMAIL=${sendmailPath}
     # Purity: force atd.pid to be placed in /var/run regardless of
     # whether it exists now.
-    substituteInPlace ./configure --replace "test -d /var/run" "true"
+    substituteInPlace ./configure --replace-fail "test -d /var/run" "true"
   '';
 
   configureFlags = [