diff --git a/.coveralls.yml b/.coveralls.yml
deleted file mode 100644
index fe82e42b..00000000
--- a/.coveralls.yml
+++ /dev/null
@@ -1,3 +0,0 @@
-coverage_clover: coveralls.clover
-service_name: travis-ci
-json_path: ./coveralls.json
diff --git a/.travis.yml b/.travis.yml
index d1efe231..b6afbb8c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,7 +7,7 @@ php:
   - 7.4
 env:
   global:
-    - ES_VERSION=6.2.3 ES_DOWNLOAD_URL=https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-${ES_VERSION}.tar.gz
+    - ES_VERSION=6.8.2 ES_DOWNLOAD_URL=https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-${ES_VERSION}.tar.gz
   matrix:
     - SYMFONY="^4.4"
     - SYMFONY="^5.0"
@@ -28,4 +28,4 @@ script:
   - vendor/bin/phpunit --coverage-clover=coverage.clover
   - vendor/bin/phpcs -p --standard=PSR2 --ignore=vendor/,Tests/app/,var/cache ./
 after_script:
-  - travis_retry php vendor/bin/coveralls
+  - travis_retry bash <(curl -s https://codecov.io/bash)
diff --git a/Mapping/Caser.php b/Mapping/Caser.php
index 6a0022ae..073e0475 100644
--- a/Mapping/Caser.php
+++ b/Mapping/Caser.php
@@ -11,13 +11,19 @@
 
 namespace ONGR\ElasticsearchBundle\Mapping;
 
-use Doctrine\Common\Inflector\Inflector;
+use Doctrine\Inflector\Inflector;
+use Doctrine\Inflector\InflectorFactory;
 
 /**
  * Utility for string case transformations.
  */
 class Caser
 {
+    /**
+     * @var Inflector|null
+     */
+    private static $inflector;
+
     /**
      * Transforms string to camel case (e.g., resultString).
      *
@@ -27,7 +33,11 @@ class Caser
      */
     public static function camel($string)
     {
-        return Inflector::camelize($string);
+        if (!self::$inflector) {
+            self::$inflector = InflectorFactory::create()->build();
+        }
+
+        return self::$inflector->camelize($string);
     }
 
     /**
diff --git a/README.md b/README.md
index 13157a8f..f3212f8c 100644
--- a/README.md
+++ b/README.md
@@ -23,6 +23,7 @@ is the preferred and recommended way to ask questions about ONGR bundles and lib
 
 
 [![Build Status](https://travis-ci.org/ongr-io/ElasticsearchBundle.svg?branch=master)](https://travis-ci.org/ongr-io/ElasticsearchBundle)
+[![codecov](https://codecov.io/gh/ongr-io/ElasticsearchBundle/branch/master/graph/badge.svg)](https://codecov.io/gh/ongr-io/ElasticsearchBundle)
 [![Latest Stable Version](https://poser.pugx.org/ongr/elasticsearch-bundle/v/stable)](https://packagist.org/packages/ongr/elasticsearch-bundle)
 [![Total Downloads](https://poser.pugx.org/ongr/elasticsearch-bundle/downloads)](https://packagist.org/packages/ongr/elasticsearch-bundle)
 [![Scrutinizer Code Quality](https://scrutinizer-ci.com/g/ongr-io/ElasticsearchBundle/badges/quality-score.png?b=master)](https://scrutinizer-ci.com/g/ongr-io/ElasticsearchBundle/?branch=master)
diff --git a/composer.json b/composer.json
index defe1790..62752e90 100644
--- a/composer.json
+++ b/composer.json
@@ -22,7 +22,7 @@
         "symfony/property-access": "^4.4|^5.0",
         "doctrine/annotations": "^1.6",
         "doctrine/cache": "^1.7",
-        "doctrine/inflector": "^1.3",
+        "doctrine/inflector": "^1.4 || ^2.0",
         "doctrine/collections": "^1.5",
         "monolog/monolog": "^1.24",
         "elasticsearch/elasticsearch": "^6.0",