diff --git a/.gitignore b/.gitignore
index da734f1..0013978 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,5 @@
 .puli/
-build/
 vendor/
 composer.lock
-phpspec.yml
 phpunit.xml
+.phpunit.result.cache
diff --git a/.travis.yml b/.travis.yml
index 3f32e86..cd3dbe9 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,5 +1,4 @@
 language: php
-
 sudo: false
 
 cache:
@@ -7,11 +6,9 @@ cache:
         - $HOME/.composer/cache/files
 
 php:
-    - 5.5
-    - 5.6
-    - 7.0
     - 7.1
-    - hhvm
+    - 7.2
+    - 7.3
 
 env:
     global:
@@ -24,14 +21,12 @@ branches:
 matrix:
     fast_finish: true
     include:
-        - php: 5.5
+        - php: 7.3
           env: COMPOSER_FLAGS="--prefer-stable --prefer-lowest" COVERAGE=true TEST_COMMAND="composer test-ci"
 
-before_install:
-    - travis_retry composer self-update
 
 install:
-    - travis_retry composer update ${COMPOSER_FLAGS} --prefer-source --no-interaction
+    - composer update ${COMPOSER_FLAGS} --prefer-dist --no-interaction
 
 script:
     - $TEST_COMMAND
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1f0ee3d..146f73a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,10 @@
 # Change Log
 
+## UNRELEASED
+
+- Added support for PSR-17 factories.
+- Dropped support for PHP < 7.2
+
 ## 1.0.0 - 2017-05-21
 
 No changes from 0.2.0.
diff --git a/composer.json b/composer.json
index bc193ef..329e906 100644
--- a/composer.json
+++ b/composer.json
@@ -11,15 +11,16 @@
         }
     ],
     "require": {
-        "php": "^5.5 || ^7.0",
+        "php": "^7.1",
         "psr/http-message": "^1.0",
+        "psr/http-factory": "^1.0",
         "php-http/message-factory": "^1.0.2",
-        "php-http/discovery": "^1.0"
+        "php-http/discovery": "^1.7"
     },
     "require-dev": {
-        "phpunit/phpunit": "^4.8 || ^5.4",
+        "phpunit/phpunit": "^7.5 || ^8.3",
         "php-http/message": "^1.5",
-        "zendframework/zend-diactoros": "^1.3.5"
+        "nyholm/psr7": "^1.0"
     },
     "autoload": {
         "psr-4": {
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 1277304..8c0f5b8 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -5,7 +5,7 @@
          convertErrorsToExceptions="true"
          convertNoticesToExceptions="true"
          convertWarningsToExceptions="true"
-         syntaxCheck="true">
+>
     <testsuites>
         <testsuite name="MultipartStream tests">
             <directory suffix="Test.php">./tests</directory>
diff --git a/src/MultipartStreamBuilder.php b/src/MultipartStreamBuilder.php
index 8622c00..4652210 100644
--- a/src/MultipartStreamBuilder.php
+++ b/src/MultipartStreamBuilder.php
@@ -2,8 +2,11 @@
 
 namespace Http\Message\MultipartStream;
 
+use Http\Discovery\Exception\NotFoundException;
+use Http\Discovery\Psr17FactoryDiscovery;
 use Http\Discovery\StreamFactoryDiscovery;
-use Http\Message\StreamFactory;
+use Http\Message\StreamFactory as HttplugStreamFactory;
+use Psr\Http\Message\StreamFactoryInterface;
 use Psr\Http\Message\StreamInterface;
 
 /**
@@ -16,7 +19,7 @@
 class MultipartStreamBuilder
 {
     /**
-     * @var StreamFactory
+     * @var StreamFactory|StreamFactoryInterface
      */
     private $streamFactory;
 
@@ -36,11 +39,37 @@ class MultipartStreamBuilder
     private $data = [];
 
     /**
-     * @param StreamFactory|null $streamFactory
+     * @param StreamFactory|StreamFactoryInterface|null $streamFactory
      */
-    public function __construct(StreamFactory $streamFactory = null)
+    public function __construct($streamFactory = null)
     {
-        $this->streamFactory = $streamFactory ?: StreamFactoryDiscovery::find();
+        if ($streamFactory instanceof StreamFactoryInterface || $streamFactory instanceof HttplugStreamFactory) {
+            $this->streamFactory = $streamFactory;
+
+            return;
+        }
+
+        if (null !== $streamFactory) {
+            throw new \LogicException(sprintf(
+                'First arguemnt to the constructor of "%s" must be of type "%s", "%s" or null. Got %s',
+                __CLASS__,
+                StreamFactoryInterface::class,
+                HttplugStreamFactory::class,
+                \is_object($streamFactory) ? \get_class($streamFactory) : \gettype($streamFactory)
+            ));
+        }
+
+        // Try to find a stream factory.
+        try {
+            $this->streamFactory = Psr17FactoryDiscovery::findStreamFactory();
+        } catch (NotFoundException $psr17Exception) {
+            try {
+                $this->streamFactory = StreamFactoryDiscovery::find();
+            } catch (NotFoundException $httplugException) {
+                // we could not find any factory.
+                throw $psr17Exception;
+            }
+        }
     }
 
     /**
@@ -58,7 +87,7 @@ public function __construct(StreamFactory $streamFactory = null)
      */
     public function addResource($name, $resource, array $options = [])
     {
-        $stream = $this->streamFactory->createStream($resource);
+        $stream = $this->createStream($resource);
 
         // validate options['headers'] exists
         if (!isset($options['headers'])) {
@@ -108,7 +137,7 @@ public function build()
         // Append end
         $streams .= "--{$this->getBoundary()}--\r\n";
 
-        return $this->streamFactory->createStream($streams);
+        return $this->createStream($streams);
     }
 
     /**
@@ -275,4 +304,31 @@ private function basename($path)
 
         return $filename;
     }
+
+    /**
+     * @param string|resource|StreamInterface $resource
+     *
+     * @return StreamInterface
+     */
+    private function createStream($resource)
+    {
+        if ($resource instanceof StreamInterface) {
+            return $resource;
+        }
+
+        if ($this->streamFactory instanceof HttplugStreamFactory) {
+            return $this->streamFactory->createStream($resource);
+        }
+
+        // Assert: We are using a PSR17 stream factory.
+        if (\is_string($resource)) {
+            return $this->streamFactory->createStream($resource);
+        }
+
+        if (\is_resource($resource)) {
+            return $this->streamFactory->createStreamFromResource($resource);
+        }
+
+        throw new \InvalidArgumentException(sprintf('First argument to "%s::createStream()" must be a string, resource or StreamInterface.', __CLASS__));
+    }
 }
diff --git a/tests/CustomMimetypeHelperTest.php b/tests/CustomMimetypeHelperTest.php
index d8d1f10..185c35c 100644
--- a/tests/CustomMimetypeHelperTest.php
+++ b/tests/CustomMimetypeHelperTest.php
@@ -3,8 +3,9 @@
 namespace tests\Http\Message\MultipartStream;
 
 use Http\Message\MultipartStream\CustomMimetypeHelper;
+use PHPUnit\Framework\TestCase;
 
-class CustomMimetypeHelperTest extends \PHPUnit_Framework_TestCase
+class CustomMimetypeHelperTest extends TestCase
 {
     public function testGetMimetypeFromExtension()
     {
diff --git a/tests/FunctionTest.php b/tests/FunctionTest.php
index 10d16d4..3d9c6ea 100644
--- a/tests/FunctionTest.php
+++ b/tests/FunctionTest.php
@@ -2,13 +2,18 @@
 
 namespace tests\Http\Message\MultipartStream;
 
+use Http\Message\MultipartStream\CustomMimetypeHelper;
 use Http\Message\MultipartStream\MultipartStreamBuilder;
-use Zend\Diactoros\Stream;
+use Nyholm\Psr7\Factory\HttplugFactory;
+use Nyholm\Psr7\Factory\Psr17Factory;
+use Nyholm\Psr7\Stream;
+use PHPUnit\Framework\TestCase;
+use Psr\Http\Message\StreamInterface;
 
 /**
  * @author Tobias Nyholm <tobias.nyholm@gmail.com>
  */
-class FunctionTest extends \PHPUnit_Framework_TestCase
+class FunctionTest extends TestCase
 {
     public function testSupportStreams()
     {
@@ -46,7 +51,7 @@ public function testSupportURIResources()
         $this->assertTrue(false !== strpos($multipartStream, 'Content-Type: image/png'));
 
         $urlContents = file_get_contents($url);
-        $this->assertContains($urlContents, $multipartStream);
+        $this->assertStringContainsString($urlContents, $multipartStream);
     }
 
     public function testResourceFilenameIsNotLocaleAware()
@@ -139,20 +144,54 @@ public function testReset()
 
         $builder->reset();
         $multipartStream = (string) $builder->build();
-        $this->assertNotContains('foobar', $multipartStream, 'Stream should not have any data after reset()');
+        $this->assertStringNotContainsString('foobar', $multipartStream, 'Stream should not have any data after reset()');
         $this->assertNotEquals($boundary, $builder->getBoundary(), 'Stream should have a new boundary after reset()');
         $this->assertNotEmpty($builder->getBoundary());
     }
 
+    public function testThrowsExceptionIfNotStreamCompatible()
+    {
+        $builder = new MultipartStreamBuilder();
+        $this->expectException(\InvalidArgumentException::class);
+        $builder->addResource('foo', []);
+    }
+
+    public function testThrowsExceptionInConstructor()
+    {
+        $this->expectException(\LogicException::class);
+        new MultipartStreamBuilder(new CustomMimetypeHelper());
+    }
+
+    /**
+     * @dataProvider getStreamFactories
+     */
+    public function testSupportDifferentFactories($factory)
+    {
+        $resource = fopen(__DIR__.'/Resources/httplug.png', 'r');
+
+        $builder = new MultipartStreamBuilder($factory);
+        $builder->addResource('image', $resource);
+
+        $multipartStream = (string) $builder->build();
+        $this->assertTrue(false !== strpos($multipartStream, 'Content-Disposition: form-data; name="image"; filename="httplug.png"'));
+        $this->assertTrue(false !== strpos($multipartStream, 'Content-Type: image/png'));
+    }
+
+    public function getStreamFactories()
+    {
+        yield 'Httplug Stream Factory' => [new HttplugFactory()];
+        yield 'PSR-17 Stream Factory' => [new Psr17Factory()];
+        yield 'Null Stream Factory' => [null];
+    }
+
     /**
      * @param string $body
      *
-     * @return Stream
+     * @return StreamInterface
      */
     private function createStream($body)
     {
-        $stream = new Stream('php://memory', 'rw');
-        $stream->write($body);
+        $stream = Stream::create($body);
         $stream->rewind();
 
         return $stream;