diff --git a/lib/contracts/contract_deployer.js b/lib/contracts/contract_deployer.js
index 71cd6900..69192692 100644
--- a/lib/contracts/contract_deployer.js
+++ b/lib/contracts/contract_deployer.js
@@ -152,16 +152,16 @@ class ContractDeployer {
           accounts = _accounts;
 
           // applying deployer account configuration, if any
-          if (typeof contract.fromIndex == 'number') {
+          if (typeof contract.fromIndex === 'number') {
             deploymentAccount = accounts[contract.fromIndex];
             if (deploymentAccount === undefined) {
               return next(__("error deploying") + " " + contract.className + ": " + __("no account found at index") + " " + contract.fromIndex + __(" check the config"));
             }
           }
-          if (typeof contract.from == 'string' && typeof contract.fromIndex != 'undefined') {
+          if (typeof contract.from === 'string' && typeof contract.fromIndex !== 'undefined') {
             self.logger.warn(__('Both "from" and "fromIndex" are defined for contract') + ' "' + contract.className + '". ' + __('Using "from" as deployer account.'));
           }
-          if (typeof contract.from == 'string') {
+          if (typeof contract.from === 'string') {
             deploymentAccount = contract.from;
           }