diff --git a/.gitignore b/.gitignore
index 08161e2..2b73834 100644
--- a/.gitignore
+++ b/.gitignore
@@ -8,6 +8,9 @@ npm-debug.log
 .DS_Store
 .esm-cache
 
+# Bundle
+target
+
 # Typescript
 *.tsbuildinfo
 .tsbuildinfo
diff --git a/.travis.yml b/.travis.yml
index 3b571ee..885debd 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,10 +1,19 @@
 language: node_js
 node_js:
+  - "6"
   - "8"
   - "10"
   - "12"
   - "13"
 sudo: false
+
 cache:
   directories:
     - node_modules
+
+install:
+  - yarn install --ignore-engines
+
+script:
+  - 'if [ "${TRAVIS_NODE_VERSION}" = "6" ] ; then yarn build:tsc ; else yarn build:microbundle ; fi ;'
+  - yarn test
diff --git a/example/jsonrpc.js b/example/jsonrpc.js
deleted file mode 100644
index b8a8257..0000000
--- a/example/jsonrpc.js
+++ /dev/null
@@ -1,59 +0,0 @@
-"use strict";
-
-const jsonrpc = require('../jsonrpc');
-
-const requestObj = jsonrpc.request('123', 'update', {list: [1, 2, 3]});
-const notificationObj = jsonrpc.notification('update', {list: [1, 2, 3]})
-const successObj = jsonrpc.success('123', 'OK')
-const errorObj = jsonrpc.error('123', new jsonrpc.JsonRpcError('some error', 99))
-const parseObj = jsonrpc.parse('{"jsonrpc": "2.0", "method": "subtract", "params": [42, 23], "id": 1}')
-const parseObjBatch = jsonrpc.parse(
-    JSON.stringify([
-        {'jsonrpc': '2.0', 'method': 'sum', 'params': [1, 2, 4], 'id': '1'},
-        {'jsonrpc': '2.0', 'method': 'foo.get', 'params': {'name': 'myself'}},
-        {'jsonrpc': '2.0', 'result': 19, 'id': '2'},
-        {'jsonrpc': '2.0', 'error': {'code': -32600, 'message': 'Invalid Request'}, 'id': null},
-      ])
-)
-
-console.log(requestObj)
-console.log(notificationObj)
-console.log(successObj)
-console.log(errorObj)
-console.log(parseObj)
-console.log(parseObjBatch)
-
-// RequestObject {
-//     jsonrpc: '2.0',
-//     id: '123',
-//     method: 'update',
-//     params: { list: [ 1, 2, 3 ] } }
-//   NotificationObject {
-//     jsonrpc: '2.0',
-//     method: 'update',
-//     params: { list: [ 1, 2, 3 ] } }
-//   SuccessObject { jsonrpc: '2.0', id: '123', result: 'OK' }
-//   ErrorObject {
-//     jsonrpc: '2.0',
-//     id: '123',
-//     error: JsonRpcError { message: 'some error', code: 99 } }
-//   JsonRpcParsed {
-//     payload:
-//      RequestObject { jsonrpc: '2.0', id: 1, method: 'subtract', params: [ 42, 23 ] },
-//     type: 'request' }
-// [ JsonRpcParsed {
-//     payload:
-//      RequestObject { jsonrpc: '2.0', id: '1', method: 'sum', params: [Array] },
-//     type: 'request' },
-//   JsonRpcParsed {
-//     payload:
-//      NotificationObject { jsonrpc: '2.0', method: 'foo.get', params: [Object] },
-//     type: 'notification' },
-//   JsonRpcParsed {
-//     payload: SuccessObject { jsonrpc: '2.0', id: '2', result: 19 },
-//     type: 'success' },
-//   JsonRpcParsed {
-//     payload:
-//      ErrorObject { jsonrpc: '2.0', id: null, error: [JsonRpcError] },
-//     type: 'error' } ]
-
diff --git a/package.json b/package.json
index 8e5b522..8efbee8 100644
--- a/package.json
+++ b/package.json
@@ -6,7 +6,7 @@
   ],
   "license": "MIT",
   "version": "2.1.0",
-  "source": "src/main/ts/index.ts",
+  "source": "jsonrpc.ts",
   "main": "jsonrpc.js",
   "module": "jsonrpc.mjs",
   "unpkg": "jsonrpc.umd.js",
@@ -42,10 +42,10 @@
   },
   "scripts": {
     "build:tsc": "tsc -p tsconfig.build.json",
-    "build:microbundle": "microbundle jsonrpc.ts --name jsonrpc --strict",
+    "build:microbundle": "microbundle build jsonrpc.ts --name jsonrpc --strict",
     "build": "yarn build:microbundle",
     "lint": "tslint -p tsconfig.json -t stylish jsonrpc.ts",
-    "test": "npm run lint && tman"
+    "test": "yarn lint && tman"
   },
   "files": [
     "README.md",
diff --git a/test/index.js b/test/index.js
index a9798c9..357336e 100644
--- a/test/index.js
+++ b/test/index.js
@@ -4,8 +4,11 @@ const assert = require('assert')
 const tman = require('tman')
 
 test(require('../jsonrpc.js'))
-test(require('../jsonrpc.umd'))
-test(require('esm')(module)('../jsonrpc.mjs'))
+
+if (!process.version.match(/^v(6\.\d+)/)) {
+  test(require('../jsonrpc.umd'))
+  test(require('esm')(module)('../jsonrpc.mjs'))
+}
 
 require('ts-node/register')
 test(require('../jsonrpc.ts').default)