lib/contracts/contributor.js

@@ -9,7 +9,8 @@ class Contributor extends Record {
 
   getById (id) {
     return this.functions.getContributorById(id)
-      .then(data => {
+      .then(contractData => {
+        let data = {...contractData};
         data.balanceInt = formatKredits(data.balance);
         return this.ipfs.catAndMerge(data, ContributorSerializer.deserialize);
       });

lib/utils/ipfs.js

@@ -11,7 +11,8 @@ class IPFS {
     this._ipfsAPI = ipfsClient(config);
   }
 
-  catAndMerge (data, deserialize) {
+  catAndMerge (contractData, deserialize) {
+    let data = {...contractData}; // data from ethers.js is not extensible. this copy the attributes in a new object
     // if no hash details are found simply return the data; nothing to merge
     if (!data.hashSize || data.hashSize === 0) {
       return data;