diff --git a/lib/constants.json b/lib/constants.json
index bedc38d22..c659b42e4 100644
--- a/lib/constants.json
+++ b/lib/constants.json
@@ -13,10 +13,6 @@
     "reset": "reset",
     "any": "any"
   },
-  "events": {
-    "contractFilesChanged": "contractFilesChanged",
-    "contractConfigChanged": "contractConfigChanged"
-  },
   "process": {
     "processLaunchRequest": "process:launch-request",
     "processLaunchComplete": "process:launch-complete",
diff --git a/lib/core/config.js b/lib/core/config.js
index 1ad0c8f2c..66e3259b4 100644
--- a/lib/core/config.js
+++ b/lib/core/config.js
@@ -222,7 +222,6 @@ Config.prototype.loadContractsConfigFile = function() {
   const newContractsConfig = this._mergeConfig(configFilePath, configObject, this.env);
 
   if (!deepEqual(newContractsConfig, this.contractsConfig)) {
-    this.events.emit(constants.events.contractConfigChanged, newContractsConfig);
     this.contractsConfig = newContractsConfig;
   }
 };
@@ -333,8 +332,11 @@ Config.prototype.loadEmbarkConfigFile = function() {
   const contracts = this.embarkConfig.contracts;
   const newContractsFiles = this.loadFiles(contracts);
   if (!this.contractFiles || newContractsFiles.length !== this.contractFiles.length || !deepEqual(newContractsFiles, this.contractFiles)) {
-    this.events.emit(constants.events.contractFilesChanged, newContractsFiles);
-    this.contractsFiles = newContractsFiles;
+    this.contractsFiles = this.contractsFiles.concat(newContractsFiles).filter((file, index, arr) => {
+      return !arr.some((file2, index2) => {
+        return file.filename === file2.filename && index < index2;
+      });
+    });
   }
   // determine contract 'root' directories
   this.contractDirectories = contracts.map((dir) => {
diff --git a/lib/tests/test.js b/lib/tests/test.js
index da444e9db..ae9696e98 100644
--- a/lib/tests/test.js
+++ b/lib/tests/test.js
@@ -2,7 +2,6 @@ const async = require('async');
 const Engine = require('../core/engine.js');
 const TestLogger = require('./test_logger.js');
 const Web3 = require('web3');
-const constants = require('../constants');
 const Events = require('../core/events');
 const AccountParser = require('../utils/accountParser');
 // TODO: breaks module isolation; tests need to be refactored to use the engine and avoid this
@@ -272,7 +271,6 @@ class Test {
     async.waterfall([
       function getConfig(next) {
         self.engine.config.contractsConfig = {contracts: config.contracts, versions: self.versions_default};
-        self.engine.events.emit(constants.events.contractConfigChanged, self.engine.config.contractsConfig);
         next();
       },
       function getAccounts(next) {