diff --git a/README.md b/README.md
index 9746ea1..79b99b8 100644
--- a/README.md
+++ b/README.md
@@ -61,9 +61,8 @@ $container->withWait(new WaitForExec(['mysqladmin', 'ping', '-h', '127.0.0.1']),
 // Wait until that message is in the logs
 $container->withWait(new WaitForLog('Ready to accept connections'));
 
-
-// Wait for an HTTP request to succeed
-$container->withWait(new WaitForHttp($port, $method = 'GET', $path = '/'));
+// Wait for an http request to succeed
+$container->withWait((new WaitForHttp($port))->withMethod('GET')->withPath('/'));
 
 // Wait for all bound ports to be open
 $container->withWait(new WaitForHostPort());
diff --git a/src/Container/StartedGenericContainer.php b/src/Container/StartedGenericContainer.php
index 5ae3f82..6e2acdd 100644
--- a/src/Container/StartedGenericContainer.php
+++ b/src/Container/StartedGenericContainer.php
@@ -98,6 +98,9 @@ public function logs(): string
             ?->getBody()
             ->getContents() ?? '';
 
+        /**
+         * @var string|false $converted
+         */
         $converted = mb_convert_encoding($output, 'UTF-8', 'UTF-8');
         return $this->sanitizeOutput($converted == false ? $output : $converted);
     }
diff --git a/src/Wait/WaitForHttp.php b/src/Wait/WaitForHttp.php
index 855c55f..31d4c08 100644
--- a/src/Wait/WaitForHttp.php
+++ b/src/Wait/WaitForHttp.php
@@ -147,8 +147,8 @@ private function makeHttpRequest(string $url): int
 
     private function resolvePort(StartedTestContainer $container): void
     {
-        if ($this->port === null) {
-            $this->port = $container->getFirstMappedPort();
-        }
+        $this->port = $this->port === null
+            ? $container->getFirstMappedPort()
+            : $container->getMappedPort($this->port);
     }
 }
diff --git a/tests/Integration/GenericContainerTest.php b/tests/Integration/GenericContainerTest.php
index 7ed65bb..0b4188f 100644
--- a/tests/Integration/GenericContainerTest.php
+++ b/tests/Integration/GenericContainerTest.php
@@ -8,6 +8,7 @@
 use PHPUnit\Framework\TestCase;
 use Testcontainers\Container\GenericContainer;
 use Testcontainers\Wait\WaitForHostPort;
+use Testcontainers\Wait\WaitForHttp;
 
 class GenericContainerTest extends TestCase
 {
@@ -111,7 +112,7 @@ public function testShouldCopyFileWithPermissions(): void
         $container->stop();
     }
 
-    public function testShouldReturnFirstMappedPort(): void
+    public function testShouldReturnFirstMappedPortWithWaitForHostPort(): void
     {
         $container = (new GenericContainer('nginx'))
             ->withExposedPorts(80)
@@ -124,6 +125,32 @@ public function testShouldReturnFirstMappedPort(): void
         $container->stop();
     }
 
+    public function testShouldReturnFirstMappedPortWithWaitForHttp(): void
+    {
+        $container = (new GenericContainer('nginx'))
+            ->withExposedPorts(80)
+            ->withWait((new WaitForHttp())->withMethod('GET')->withPath('/'))
+            ->start();
+        $firstMappedPort = $container->getFirstMappedPort();
+
+        self::assertSame($firstMappedPort, $container->getMappedPort(80));
+
+        $container->stop();
+    }
+
+    public function testShouldReturnMappedPortWithWaitForHttp(): void
+    {
+        $container = (new GenericContainer('nginx'))
+            ->withExposedPorts(80)
+            ->withWait((new WaitForHttp(80))->withMethod('GET')->withPath('/'))
+            ->start();
+        $mappedPort = $container->getMappedPort(80);
+
+        self::assertSame($mappedPort, $container->getFirstMappedPort());
+
+        $container->stop();
+    }
+
     public function testShouldSetLabels(): void
     {
         $labels = [