diff --git a/lib/sandbox/pmapi.js b/lib/sandbox/pmapi.js
index <HASH>..<HASH> 100644
--- a/lib/sandbox/pmapi.js
+++ b/lib/sandbox/pmapi.js
@@ -2,11 +2,11 @@ var EXECUTION_ASSERTION_EVENT = 'execution.assertion',
     EXECUTION_ASSERTION_EVENT_BASE = 'execution.assertion.',
 
     _ = require('lodash'),
-    VariableScope = require('postman-collection').VariableScope,
-    PostmanRequest = require('postman-collection').Request,
-    PostmanResponse = require('postman-collection').Response,
+    sdk = require('postman-collection'),
+    VariableScope = sdk.VariableScope,
+    PostmanRequest = sdk.Request,
+    PostmanResponse = sdk.Response,
     chai = require('chai'),
-    chaiPostman = require('./chai-postman'),
 
     /**
      * Use this function to assign readonly properties to an object
@@ -142,7 +142,7 @@ Postman = function Postman (bridge, execution, onRequest) {
 Postman.prototype.expect = chai.expect;
 
 // make chai use postman extension
-chai.use(chaiPostman);
+chai.use(require('chai-postman')(sdk));
 
 // export
 module.exports = Postman;
Replaced in-house chai assertions with chai-postman