diff --git a/nixos/modules/virtualisation/libvirtd.nix b/nixos/modules/virtualisation/libvirtd.nix
--- a/nixos/modules/virtualisation/libvirtd.nix
+++ b/nixos/modules/virtualisation/libvirtd.nix
@@ -46,6 +46,14 @@ in {
       '';
     };
 
+    package = mkOption {
+      type = types.package;
+      default = pkgs.libvirt;
+      description = ''
+        libvirt package to use.
+      '';
+    };
+
     qemuPackage = mkOption {
       type = types.package;
       default = pkgs.qemu;
@@ -169,26 +177,26 @@ in {
       source = "/run/${dirName}/nix-helpers/qemu-bridge-helper";
     };
 
-    systemd.packages = [ pkgs.libvirt ];
+    systemd.packages = [ cfg.package ];
 
     systemd.services.libvirtd-config = {
       description = "Libvirt Virtual Machine Management Daemon - configuration";
       script = ''
         # Copy default libvirt network config .xml files to /var/lib
         # Files modified by the user will not be overwritten
-        for i in $(cd ${pkgs.libvirt}/var/lib && echo \
+        for i in $(cd ${cfg.package}/var/lib && echo \
             libvirt/qemu/networks/*.xml libvirt/qemu/networks/autostart/*.xml \
             libvirt/nwfilter/*.xml );
         do
             mkdir -p /var/lib/$(dirname $i) -m 755
-            cp -npd ${pkgs.libvirt}/var/lib/$i /var/lib/$i
+            cp -npd ${cfg.package}/var/lib/$i /var/lib/$i
         done
 
         # Copy generated qemu config to libvirt directory
         cp -f ${qemuConfigFile} /var/lib/${dirName}/qemu.conf
 
         # stable (not GC'able as in /nix/store) paths for using in <emulator> section of xml configs
-        for emulator in ${pkgs.libvirt}/libexec/libvirt_lxc ${cfg.qemuPackage}/bin/qemu-kvm ${cfg.qemuPackage}/bin/qemu-system-*; do
+        for emulator in ${cfg.package}/libexec/libvirt_lxc ${cfg.qemuPackage}/bin/qemu-kvm ${cfg.qemuPackage}/bin/qemu-system-*; do
           ln -s --force "$emulator" /run/${dirName}/nix-emulators/
         done
 
@@ -249,7 +257,7 @@ in {
 
     systemd.services.virtlogd = {
       description = "Virtual machine log manager";
-      serviceConfig.ExecStart = "@${pkgs.libvirt}/sbin/virtlogd virtlogd";
+      serviceConfig.ExecStart = "@${cfg.package}/sbin/virtlogd virtlogd";
       restartIfChanged = false;
     };
 
@@ -261,7 +269,7 @@ in {
 
     systemd.services.virtlockd = {
       description = "Virtual machine lock manager";
-      serviceConfig.ExecStart = "@${pkgs.libvirt}/sbin/virtlockd virtlockd";
+      serviceConfig.ExecStart = "@${cfg.package}/sbin/virtlockd virtlockd";
       restartIfChanged = false;
     };
 
diff --git a/pkgs/build-support/build-bazel-package/default.nix b/pkgs/build-support/build-bazel-package/default.nix
--- a/pkgs/build-support/build-bazel-package/default.nix
+++ b/pkgs/build-support/build-bazel-package/default.nix
@@ -126,7 +126,7 @@ in stdenv.mkDerivation (fBuildAttrs // {
       find $bazelOut/external -maxdepth 1 -type l | while read symlink; do
         name="$(basename "$symlink")"
         rm "$symlink"
-        test -f "$bazelOut/external/@$name.marker" && rm "$bazelOut/external/@$name.marker"
+        test -f "$bazelOut/external/@$name.marker" && rm "$bazelOut/external/@$name.marker" || true
       done
 
       # Patching symlinks to remove build directory reference