Comments are good

src/config.js

@@ -1,6 +1,12 @@
 const refConfig = require('./config.default.json');
 const fs = require('fs');
 
+/**
+ * Merge resources by reading object keys and keeping reference value only if it's type is different from the source
+ * @param ref - reference object/value
+ * @param src - source object/value
+ * @returns {*}
+ */
 const merge = (ref, src) => {
     if (typeof ref !== typeof src) {
         return ref;