diff --git a/.travis.yml b/.travis.yml
index 2224fd0..a0c42b3 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,8 +1,26 @@
 language: php
-php:
-- 7.1
-before_install:
-- cp phpunit.xml.sample phpunit.xml
-- composer install
-script:
-- ./vendor/bin/phpunit
+jobs:
+  include:
+    - stage: php71-lowest
+      php: 7.1
+      env: dependencies=lowest
+      script: ./vendor/bin/phpunit
+    - stage: php72-lowest
+      php: 7.2
+      env: dependencies=lowest
+      script: ./vendor/bin/phpunit
+    - stage: php72
+      php: 7.2
+      script: ./vendor/bin/phpunit
+    - stage: php73
+      php: 7.3
+      script: ./vendor/bin/phpunit
+    - stage: php74
+      php: 7.4
+      script: ./vendor/bin/phpunit
+
+before_script:
+  - composer self-update -q
+  - if [ -z "$dependencies" ]; then composer install; fi;
+  - if [ "$dependencies" = "lowest" ]; then composer update --prefer-lowest -n; fi;
+  - if [ "$dependencies" = "highest" ]; then composer update -n; fi;
diff --git a/README.md b/README.md
index 272fa73..5623f9d 100644
--- a/README.md
+++ b/README.md
@@ -311,7 +311,7 @@ In order to pass the unit tests, you will need:
 
 ### To run the tests
 
-- Copy file `phpunit.xml.sample` to `phpunit.xml`
+- Copy file `phpunit.xml.dist` to `phpunit.xml`
 - Edit the new file and enter your values for `API_KEY`, `CLIENT_ID`, `CLIENT_SECRET`, `CALLBACK_URL`, `API_URL`, AND `OAUTH_TOKEN_URL`
 - Run `./vendor/bin/phpunit`
 
diff --git a/composer.json b/composer.json
index 1cce276..de3fbca 100644
--- a/composer.json
+++ b/composer.json
@@ -17,6 +17,6 @@
         "phpunit/phpunit": "7.3.*"
     },
     "require": {
-        "guzzlehttp/guzzle": "^7.0|^6.2"
+        "guzzlehttp/guzzle": "^6.3|^7.0"
     }
 }
diff --git a/library/HelloSign/Client.php b/library/HelloSign/Client.php
index dcdaf62..f1a214b 100644
--- a/library/HelloSign/Client.php
+++ b/library/HelloSign/Client.php
@@ -41,7 +41,7 @@
 class Client
 {
 
-    const VERSION = '3.6.0';
+    const VERSION = '3.7.0';
 
     const API_URL = "https://api.hellosign.com/v3/";
 
diff --git a/library/HelloSign/Test/ApiAppTest.php b/library/HelloSign/Test/ApiAppTest.php
index b2cfca0..4751683 100644
--- a/library/HelloSign/Test/ApiAppTest.php
+++ b/library/HelloSign/Test/ApiAppTest.php
@@ -30,6 +30,12 @@
 
 class ApiAppTest extends AbstractTest
 {
+    private function generateApiAppName(string $prefix): string
+    {
+        $guid = TestUtils::generateGuid(8);
+        return $prefix . $guid;
+    }
+
     /**
     * @expectedException HelloSign\Error
     * @expectedExceptionMessage An app with the same name already exists
@@ -40,7 +46,7 @@ public function testCreateApiApp()
         $wl = array('primary_button_color' => '#626567', 'primary_button_text_color' => '#ffffff');
         $wl = json_encode($wl);
 
-        $name = "Test" . rand(1, 2000);
+        $name = $this->generateApiAppName('Test');
         $domain = "www.testdomain.com";
         $callback = $_ENV['CALLBACK_URL'];
         $logo = __DIR__ . "/logo.jpg";
@@ -75,7 +81,7 @@ public function testCreateApiApp()
     */
     public function testCreateOauthApiApp()
     {
-        $name = "Test Oauth" . rand(1, 2000);
+        $name = $this->generateApiAppName('Test Oauth');
         $domain = "www.testdomain.com";
         $callback = $_ENV['CALLBACK_URL'];
         $logo = __DIR__ . "/logo.jpg";
@@ -104,7 +110,7 @@ public function testCreateOauthApiApp()
     public function testUpdateApiApp()
     {
 
-        $name = "Test" . rand(1, 2000);
+        $name = $this->generateApiAppName('Test');
         $domain = "www.testdomain.com";
 
         $app = new ApiApp;
@@ -131,7 +137,7 @@ public function testUpdateApiApp()
      */
     public function testGetApiApp()
     {
-        $name = "Test" . rand(1, 2000);
+        $name = $this->generateApiAppName('Test');
         $domain = "www.testdomain.com";
         $callback_url = $_ENV['CALLBACK_URL'];
 
diff --git a/library/HelloSign/Test/TemplateTest.php b/library/HelloSign/Test/TemplateTest.php
index 6388653..d45dd1a 100644
--- a/library/HelloSign/Test/TemplateTest.php
+++ b/library/HelloSign/Test/TemplateTest.php
@@ -41,7 +41,7 @@ class TemplateTest extends AbstractTest
      */
     public function testGetTemplatesWithPageNotFound()
     {
-        $templates = $this->client->getTemplates(9999);
+        $templates = $this->client->getTemplates(9999, 1);
     }
 
     /**
@@ -187,7 +187,7 @@ public function testUpdateTemplateFiles()
         $templates = $this->client->getTemplates();
         $template_id = $templates[0]->getId();
         $client_id = $_ENV['CLIENT_ID'];
-        
+
         $request = new \HelloSign\Template();
         $request->setClientId($client_id);
         $request->addFile(__DIR__ . '/nda.docx');
diff --git a/library/HelloSign/Test/TestUtils.php b/library/HelloSign/Test/TestUtils.php
new file mode 100644
index 0000000..a7b3565
--- /dev/null
+++ b/library/HelloSign/Test/TestUtils.php
@@ -0,0 +1,18 @@
+<?php
+
+namespace HelloSign\Test;
+
+class TestUtils
+{
+    /**
+     * @param int|null $length
+     * @return string
+     */
+    public static function generateGuid(?int $length = 40): string
+    {
+        $bytes = random_bytes((int) ceil($length / 2));
+        $guid = bin2hex($bytes);
+
+        return substr($guid, 0, $length);
+    }
+}
diff --git a/phpunit.xml.sample b/phpunit.xml.dist
similarity index 67%
rename from phpunit.xml.sample
rename to phpunit.xml.dist
index bd02a4b..453948b 100644
--- a/phpunit.xml.sample
+++ b/phpunit.xml.dist
@@ -6,9 +6,9 @@
         </testsuite>
     </testsuites>
     <php>
-      <env name="API_KEY" value="9dc85fe9ef819a2dc5aac48fd5b951ee2f5b6528c26dd398438fce6b355cb075"/>
-      <env name="CLIENT_ID" value="457519f7a1be8feca9f3533c00b98596"/>
-      <env name="CLIENT_SECRET" value="4798f37830ace2866b2ca5d19dd3ede5"/>
+      <env name="API_KEY" value="REPLACE_WITH_YOUR_KEY"/>
+      <env name="CLIENT_ID" value="REPLACE_WITH_YOUR_CLIENT_ID"/>
+      <env name="CLIENT_SECRET" value="REPLACE_WITH_YOUR_CLIENT_SECRET"/>
       <env name="CALLBACK_URL" value="http://example.com/callback"/>
       <env name="API_URL" value="https://api.hellosign.com/v3/"/>
       <env name="OAUTH_TOKEN_URL" value="https://app.hellosign.com/oauth/token"/>