diff --git a/src/Manipulators/BaseManipulator.php b/src/Manipulators/BaseManipulator.php
index b2f89dc..966fd1a 100644
--- a/src/Manipulators/BaseManipulator.php
+++ b/src/Manipulators/BaseManipulator.php
@@ -20,7 +20,7 @@ abstract class BaseManipulator implements ManipulatorInterface
      *
      * @return $this
      */
-    public function setParams(array $params)
+    public function setParams(array $params): static
     {
         $this->params = $params;
 
diff --git a/src/Manipulators/Helpers/Color.php b/src/Manipulators/Helpers/Color.php
index fe88f44..ca8a187 100644
--- a/src/Manipulators/Helpers/Color.php
+++ b/src/Manipulators/Helpers/Color.php
@@ -112,7 +112,7 @@ public function parseHex(string $hex): array
      *
      * @return string The formatted color.
      */
-    public function formatted()
+    public function formatted(): string
     {
         return 'rgba('.$this->red.', '.$this->green.', '.$this->blue.', '.$this->alpha.')';
     }
diff --git a/src/Manipulators/ManipulatorInterface.php b/src/Manipulators/ManipulatorInterface.php
index 93a4153..be1119f 100644
--- a/src/Manipulators/ManipulatorInterface.php
+++ b/src/Manipulators/ManipulatorInterface.php
@@ -15,7 +15,7 @@ interface ManipulatorInterface
      *
      * @return $this
      */
-    public function setParams(array $params);
+    public function setParams(array $params): static;
 
     /**
      * Get a specific manipulation param.
diff --git a/src/Manipulators/Size.php b/src/Manipulators/Size.php
index 9ab127b..5581662 100644
--- a/src/Manipulators/Size.php
+++ b/src/Manipulators/Size.php
@@ -172,7 +172,7 @@ public function resolveMissingDimensions(ImageInterface $image, ?int $width = nu
      *
      * @return int[] The modified width and height.
      */
-    public function applyDpr(int $width, int $height, float $dpr)
+    public function applyDpr(int $width, int $height, float $dpr): array
     {
         $width = $width * $dpr;
         $height = $height * $dpr;
diff --git a/src/Responses/PsrResponseFactory.php b/src/Responses/PsrResponseFactory.php
index 0c725a9..0cb6d4b 100644
--- a/src/Responses/PsrResponseFactory.php
+++ b/src/Responses/PsrResponseFactory.php
@@ -39,7 +39,7 @@ public function __construct(ResponseInterface $response, \Closure $streamCallbac
      *
      * @return ResponseInterface Response object.
      */
-    public function create(FilesystemOperator $cache, $path)
+    public function create(FilesystemOperator $cache, string $path): ResponseInterface
     {
         $stream = $this->streamCallback->__invoke(
             $cache->readStream($path)
diff --git a/src/Responses/ResponseFactoryInterface.php b/src/Responses/ResponseFactoryInterface.php
index 48dc650..f9ddeb1 100644
--- a/src/Responses/ResponseFactoryInterface.php
+++ b/src/Responses/ResponseFactoryInterface.php
@@ -16,5 +16,5 @@ interface ResponseFactoryInterface
      *
      * @return mixed The response object.
      */
-    public function create(FilesystemOperator $cache, $path);
+    public function create(FilesystemOperator $cache, string $path);
 }
diff --git a/src/Signatures/Signature.php b/src/Signatures/Signature.php
index 5c366c9..d7f96c9 100644
--- a/src/Signatures/Signature.php
+++ b/src/Signatures/Signature.php
@@ -61,7 +61,7 @@ public function validateRequest(string $path, array $params): void
      *
      * @return string The generated HTTP signature.
      */
-    public function generateSignature(string $path, array $params)
+    public function generateSignature(string $path, array $params): string
     {
         unset($params['s']);
         ksort($params);