diff --git a/module/Core/test/Action/QrCodeActionTest.php b/module/Core/test/Action/QrCodeActionTest.php
new file mode 100644
index 00000000..d4924724
--- /dev/null
+++ b/module/Core/test/Action/QrCodeActionTest.php
@@ -0,0 +1,93 @@
+<?php
+namespace ShlinkioTest\Shlink\Core\Action;
+
+use PHPUnit_Framework_TestCase as TestCase;
+use Prophecy\Argument;
+use Prophecy\Prophecy\ObjectProphecy;
+use Shlinkio\Shlink\Common\Response\QrCodeResponse;
+use Shlinkio\Shlink\Core\Action\QrCodeAction;
+use Shlinkio\Shlink\Core\Entity\ShortUrl;
+use Shlinkio\Shlink\Core\Exception\InvalidShortCodeException;
+use Shlinkio\Shlink\Core\Service\UrlShortener;
+use Zend\Diactoros\Response;
+use Zend\Diactoros\ServerRequestFactory;
+use Zend\Expressive\Router\RouterInterface;
+
+class QrCodeActionTest extends TestCase
+{
+    /**
+     * @var QrCodeAction
+     */
+    protected $action;
+    /**
+     * @var ObjectProphecy
+     */
+    protected $urlShortener;
+
+    public function setUp()
+    {
+        $router = $this->prophesize(RouterInterface::class);
+        $router->generateUri(Argument::cetera())->willReturn('/foo/bar');
+
+        $this->urlShortener = $this->prophesize(UrlShortener::class);
+
+        $this->action = new QrCodeAction($router->reveal(), $this->urlShortener->reveal());
+    }
+
+    /**
+     * @test
+     */
+    public function aNonexistentShortCodeWillReturnNotFoundResponse()
+    {
+        $shortCode = 'abc123';
+        $this->urlShortener->shortCodeToUrl($shortCode)->willReturn(null)->shouldBeCalledTimes(1);
+
+        $resp = $this->action->__invoke(
+            ServerRequestFactory::fromGlobals()->withAttribute('shortCode', $shortCode),
+            new Response(),
+            function ($req, $resp) {
+                return $resp;
+            }
+        );
+        $this->assertEquals(404, $resp->getStatusCode());
+    }
+
+    /**
+     * @test
+     */
+    public function anInvalidShortCodeWillReturnNotFoundResponse()
+    {
+        $shortCode = 'abc123';
+        $this->urlShortener->shortCodeToUrl($shortCode)->willThrow(InvalidShortCodeException::class)
+                                                       ->shouldBeCalledTimes(1);
+
+        $resp = $this->action->__invoke(
+            ServerRequestFactory::fromGlobals()->withAttribute('shortCode', $shortCode),
+            new Response(),
+            function ($req, $resp) {
+                return $resp;
+            }
+        );
+        $this->assertEquals(404, $resp->getStatusCode());
+    }
+
+    /**
+     * @test
+     */
+    public function aCorrectRequestReturnsTheQrCodeResponse()
+    {
+        $shortCode = 'abc123';
+        $this->urlShortener->shortCodeToUrl($shortCode)->willReturn(new ShortUrl())->shouldBeCalledTimes(1);
+
+        $resp = $this->action->__invoke(
+            ServerRequestFactory::fromGlobals()->withAttribute('shortCode', $shortCode),
+            new Response(),
+            function ($req, $resp) {
+                return $resp;
+            }
+        );
+
+        $this->assertInstanceOf(QrCodeResponse::class, $resp);
+        $this->assertEquals(200, $resp->getStatusCode());
+    }
+}
diff --git a/module/Core/test/Middleware/QrCodeCacheMiddlewareTest.php b/module/Core/test/Middleware/QrCodeCacheMiddlewareTest.php
new file mode 100644
index 00000000..64aac3e0
--- /dev/null
+++ b/module/Core/test/Middleware/QrCodeCacheMiddlewareTest.php
@@ -0,0 +1,69 @@
+<?php
+namespace ShlinkioTest\Shlink\Core\Middleware;
+
+use Doctrine\Common\Cache\ArrayCache;
+use Doctrine\Common\Cache\Cache;
+use PHPUnit_Framework_TestCase as TestCase;
+use Shlinkio\Shlink\Core\Middleware\QrCodeCacheMiddleware;
+use Zend\Diactoros\Response;
+use Zend\Diactoros\ServerRequestFactory;
+use Zend\Diactoros\Uri;
+
+class QrCodeCacheMiddlewareTest extends TestCase
+{
+    /**
+     * @var QrCodeCacheMiddleware
+     */
+    protected $middleware;
+    /**
+     * @var Cache
+     */
+    protected $cache;
+
+    public function setUp()
+    {
+        $this->cache = new ArrayCache();
+        $this->middleware = new QrCodeCacheMiddleware($this->cache);
+    }
+
+    /**
+     * @test
+     */
+    public function noCachedPathFallbacksToNextMiddleware()
+    {
+        $isCalled = false;
+        $this->middleware->__invoke(
+            ServerRequestFactory::fromGlobals(),
+            new Response(),
+            function ($req, $resp) use (&$isCalled) {
+                $isCalled = true;
+                return $resp;
+            }
+        );
+        $this->assertTrue($isCalled);
+    }
+
+    /**
+     * @test
+     */
+    public function cachedPathReturnsCacheContent()
+    {
+        $isCalled = false;
+        $uri = (new Uri())->withPath('/foo');
+        $this->cache->save('/foo', ['body' => 'the body', 'content-type' => 'image/png']);
+
+        $resp = $this->middleware->__invoke(
+            ServerRequestFactory::fromGlobals()->withUri($uri),
+            new Response(),
+            function ($req, $resp) use (&$isCalled) {
+                $isCalled = true;
+                return $resp;
+            }
+        );
+
+        $this->assertFalse($isCalled);
+        $resp->getBody()->rewind();
+        $this->assertEquals('the body', $resp->getBody()->getContents());
+        $this->assertEquals('image/png', $resp->getHeaderLine('Content-Type'));
+    }
+}