diff --git a/README.md b/README.md
index 4d1dc22..84dc3ee 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,6 @@
 Clockify API client
 ====================
 
-[![Build Status](https://travis-ci.org/jdecool/clockify-api.svg?branch=master)](https://travis-ci.org/jdecool/clockify-api?branch=master)
 [![Build Status](https://img.shields.io/endpoint.svg?url=https%3A%2F%2Factions-badge.atrox.dev%2Fjdecool%2Fclockify-api%2Fbadge%3Fref%3Dmaster&style=flat)](https://actions-badge.atrox.dev/jdecool/clockify-api/goto?ref=master)
 [![Scrutinizer Code Quality](https://scrutinizer-ci.com/g/jdecool/clockify-api/badges/quality-score.png?b=master)](https://scrutinizer-ci.com/g/jdecool/clockify-api/?branch=master)
 [![Latest Stable Version](https://poser.pugx.org/jdecool/clockify-api/v/stable.png)](https://packagist.org/packages/jdecool/clockify-api)
@@ -10,19 +9,16 @@ PHP client for [Clockify.me API](https://clockify.me/developers-api).
 
 ## Install it
 
-Install using [composer](https://getcomposer.org), with guzzle6-adapter:
+You need to install the library with a PSR-18 compliant HTTP client.
 
-```bash
-composer require jdecool/clockify-api php-http/guzzle6-adapter
-```
-
-Install using [composer](https://getcomposer.org), with guzzle7-adapter:
+Example using Guzzle:
 
 ```bash
-composer require jdecool/clockify-api php-http/guzzle7-adapter
+composer require jdecool/clockify-api guzzlehttp/guzzle http-interop/http-factory-guzzle
 ```
 
-The library is decoupled from any HTTP message client with [HTTPlug](http://httplug.io). That's why you need to install a client implementation `http://httplug.io/` in this example.
+The library is decoupled from any HTTP message client with [HTTPlug](http://httplug.io).
+That's why you need to install a client implementation `http://httplug.io/` in this example.
 
 ## Getting started
 
diff --git a/composer.json b/composer.json
index 7577c7c..21a73da 100644
--- a/composer.json
+++ b/composer.json
@@ -10,17 +10,17 @@
         }
     ],
     "require": {
-        "php": "^7.2",
+        "php": "^7.3",
         "ext-json": "*",
         "myclabs/php-enum": "^1.7",
-        "php-http/client-common": "^2.0",
-        "php-http/client-implementation": "^1.0",
-        "php-http/discovery": "^1.4",
-        "php-http/httplug": "^2.0"
+        "php-http/client-common": "^2.3",
+        "php-http/discovery": "^1.12",
+        "php-http/httplug": "^2.1"
     },
     "require-dev": {
         "friendsofphp/php-cs-fixer": "^2.15",
-        "php-http/mock-client": "^1.4",
+        "guzzlehttp/guzzle": "^7.0",
+        "http-interop/http-factory-guzzle": "^1.0",
         "phpstan/phpstan": "^0.11.16",
         "phpunit/phpunit": "^8.0"
     },
diff --git a/src/ClientBuilder.php b/src/ClientBuilder.php
index 2c6f438..299f7d4 100644
--- a/src/ClientBuilder.php
+++ b/src/ClientBuilder.php
@@ -6,12 +6,13 @@
 
 use Http\Client\{
     Common\HttpMethodsClient,
-    HttpClient
+    HttpClient,
 };
 use Http\Message\MessageFactory;
+use Psr\Http\Message\RequestFactoryInterface;
 use Http\Discovery\{
-    HttpClientDiscovery,
-    MessageFactoryDiscovery
+    Psr17FactoryDiscovery,
+    Psr18ClientDiscovery,
 };
 
 class ClientBuilder
@@ -19,12 +20,12 @@ class ClientBuilder
     private const ENDPOINT_V1 = 'https://api.clockify.me/api/v1/';
 
     private $httpClient;
-    private $messageFactory;
+    private $requestFactory;
 
-    public function __construct(?HttpClient $httpClient = null, ?MessageFactory $messageFactory = null)
+    public function __construct(?HttpClient $httpClient = null, ?RequestFactoryInterface $requestFactory = null)
     {
-        $this->httpClient = $httpClient ?? HttpClientDiscovery::find();
-        $this->messageFactory = $messageFactory ?? MessageFactoryDiscovery::find();
+        $this->httpClient = $httpClient ?? Psr18ClientDiscovery::find();
+        $this->requestFactory = $requestFactory ?? Psr17FactoryDiscovery::findRequestFactory();
     }
 
     public function createClientV1(string $apiKey): Client
@@ -34,7 +35,7 @@ public function createClientV1(string $apiKey): Client
 
     public function create(string $endpoint, string $apiKey): Client
     {
-        $http = new HttpMethodsClient($this->httpClient, $this->messageFactory);
+        $http = new HttpMethodsClient($this->httpClient, $this->requestFactory);
 
         return new Client($http, $endpoint, $apiKey);
     }