diff --git a/tools/nextwks-tool/main.go b/tools/nextwks-tool/main.go
index d82dbcc..1886bca 100644
--- a/tools/nextwks-tool/main.go
+++ b/tools/nextwks-tool/main.go
@@ -164,16 +164,16 @@ func obtainCertsLego(domains []string, email, backupDir, legoDir, legoPath strin
 		return fmt.Errorf("creating lego dir: %w", err)
 	}
 
-	// Build lego args (v5+: flags go after the command)
+	// Build lego args (v5+: flags go after the command, use = syntax)
 	args := []string{"run",
-		"--email", email,
+		"--email=" + email,
 		"--http",
-		"--http.port", ":80",
-		"--path", legoDir,
+		"--http.port=:80",
+		"--path=" + legoDir,
 		"--accept-tos",
 	}
 	for _, d := range domains {
-		args = append(args, "--domains", d)
+		args = append(args, "--domains="+d)
 	}
 
 	cmd := exec.Command(legoPath, args...)