diff --git a/lib/logger/cmd-serializer.js b/lib/logger/cmd-serializer.js
new file mode 100644
index 0000000000000000000000000000000000000000..f3fd49fb49be97823f23258b0072fc4f9e680dbf
--- /dev/null
+++ b/lib/logger/cmd-serializer.js
@@ -0,0 +1,6 @@
+module.exports = cmdSerializer;
+
+// istanbul ignore next
+function cmdSerializer(cmd) {
+  return cmd.replace(/https:\/\/[^@]*@/g, 'https://**redacted**@');
+}
diff --git a/lib/logger/index.js b/lib/logger/index.js
index 47225db3719f5f69db15ad57bc35eabf0cb917fc..b0bfea56378deb83f077124a00b11b37b4d59357 100644
--- a/lib/logger/index.js
+++ b/lib/logger/index.js
@@ -3,15 +3,11 @@ const bunyan = require('bunyan');
 const PrettyStdout = require('./pretty-stdout').RenovateStream;
 const configSerializer = require('./config-serializer');
 const errSerializer = require('./err-serializer');
+const cmdSerializer = require('./cmd-serializer');
 
 let bunyanLogger;
 let meta = {};
 
-// istanbul ignore next
-function cmdSerializer(cmd) {
-  return cmd.replace(/https:\/\/[^@]*@/g, 'https://**redacted**@');
-}
-
 function initLogger() {
   const stdout = {
     name: 'stdout',