diff --git a/main.go b/main.go
index 1907ef8..d6f8b64 100644
--- a/main.go
+++ b/main.go
@@ -120,6 +120,8 @@ func main() {
 		log.Fatal(err)
 	}
 
+	sp := strings.Split(filepath.Base(*tsTarballPath), "_")
+
 	binPath, err := exec.LookPath("tar")
 	if err != nil {
 		log.Fatal(err)
@@ -131,4 +133,17 @@ func main() {
 	if err := cmd.Run(); err != nil {
 		log.Fatal(err)
 	}
+
+	{
+		binPath, err := exec.LookPath("mksquashfs")
+		if err != nil {
+			log.Fatal(err)
+		}
+		cmd := exec.Command(binPath, tmpDir, fmt.Sprintf("%s/tailscale_sysext_%s.raw", *out, sp[1]), "-quiet", "-noappend", "-all-root", "-root-mode", "755", "-b", "1M", "-comp", "xz", "-Xdict-size", "100%")
+		cmd.Stderr = os.Stderr
+		cmd.Stdout = os.Stdout
+		if err := cmd.Run(); err != nil {
+			log.Fatal(err)
+		}
+	}
 }