diff --git a/Justfile b/Justfile
index e55d737..7783df3 100755
--- a/Justfile
+++ b/Justfile
@@ -50,7 +50,8 @@ rebuild-this-device rebuildarg="dry-activate":
 		echo System rebuild successful
 	else
 		cat ${SYSREBUILD_LOG}
-		echo System rebuild failed
+		echo ERROR: system rebuild failed
+		exit 1
 	fi
 
 	if type home-manager > /dev/null 2>&1; then
@@ -60,7 +61,8 @@ rebuild-this-device rebuildarg="dry-activate":
 			echo Home rebuild successful
 		else
 			cat ${HOMEREBUILD_LOG}
-			echo Home rebuild failed
+			echo ERROR: home rebuild failed
+			exit 1
 		fi
 	fi
 
@@ -71,7 +73,7 @@ rebuild-this-device rebuildarg="dry-activate":
 # Update the channel versions and (by default) switch to new environment
 update-this-device rebuild-mode='switch':
 	#!/usr/bin/env bash
-	set -xe
+	set -e
 
 	template=nix/os/devices/$(hostname -s)/versions.tmpl.nix
 	outfile=nix/os/devices/$(hostname -s)/versions.nix
@@ -89,12 +91,14 @@ update-this-device rebuild-mode='switch':
 		exit 1
 	}
 
-	git commit -v ${outfile} -m "nix/os/devices/$(hostname -s): bump versions"
-
 	just -v rebuild-this-device {{rebuild-mode}} || {
-		echo WARNING: Rebuilding in {{rebuild-mode}}-mode failed
+		echo ERROR: Rebuilding in {{rebuild-mode}}-mode failed
+		git checkout ${outfile}
+		exit 1
 	}
 
+	git commit -v ${outfile} -m "nix/os/devices/$(hostname -s): bump versions"
+
 # Iterate on a qtile config by running it inside Xephyr. (un-/grab the mouse with Ctrl + Shift-L)
 hm-iterate-qtile:
 	#!/usr/bin/env bash