diff --git a/composer.json b/composer.json
index 55ace45..5631d74 100644
--- a/composer.json
+++ b/composer.json
@@ -33,7 +33,7 @@
         "symfony/process": "^5.2"
     },
     "provide": {
-        "psr/http-message-implementation": "1.0",
+        "psr/http-message-implementation": "2.0",
         "psr/http-factory-implementation": "1.0"
     },
     "scripts": {
diff --git a/composer.lock b/composer.lock
index e72c438..2fb4152 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "f9394aa4c519ac102a8998c5564a32f3",
+    "content-hash": "b05ceaccda26818c3c14d1bc0ada3173",
     "packages": [],
     "packages-dev": [
         {
@@ -4381,7 +4381,7 @@
     ],
     "aliases": [],
     "minimum-stability": "stable",
-    "stability-flags": [],
+    "stability-flags": {},
     "prefer-stable": false,
     "prefer-lowest": false,
     "platform": {
@@ -4389,6 +4389,6 @@
         "ext-curl": "*",
         "ext-mbstring": "*"
     },
-    "platform-dev": [],
+    "platform-dev": {},
     "plugin-api-version": "2.6.0"
 }
diff --git a/src/Message/Factory/Factory.php b/src/Message/Factory/Factory.php
index f4e75c1..b0b79ad 100644
--- a/src/Message/Factory/Factory.php
+++ b/src/Message/Factory/Factory.php
@@ -182,7 +182,7 @@ public function createUriFromArray(array $server): Uri
         }
 
         if (isset($server['SERVER_PORT'])) {
-            $uri = $uri->withPort($server['SERVER_PORT']);
+            $uri = $uri->withPort((int) $server['SERVER_PORT']);
         }
 
         if (isset($server['REQUEST_URI'])) {
diff --git a/src/Message/MessageTrait.php b/src/Message/MessageTrait.php
index 6094af1..317d4da 100644
--- a/src/Message/MessageTrait.php
+++ b/src/Message/MessageTrait.php
@@ -40,7 +40,7 @@ public function getProtocolVersion(): string
      *
      * @return self
      */
-    public function withProtocolVersion($version): self
+    public function withProtocolVersion(string $version): self
     {
         $this->validateProtocolVersion($version);
 
@@ -69,12 +69,8 @@ public function getHeaders(): array
      *
      * @return bool
      */
-    public function hasHeader($name): bool
+    public function hasHeader(string $name): bool
     {
-        if (!\is_string($name)) {
-            throw new \InvalidArgumentException('Header name must be a string');
-        }
-
         return isset($this->headerNames[\mb_strtolower($name)]);
     }
 
@@ -85,12 +81,8 @@ public function hasHeader($name): bool
      *
      * @return array
      */
-    public function getHeader($name): array
+    public function getHeader(string $name): array
     {
-        if (!\is_string($name)) {
-            throw new \InvalidArgumentException('Header name must be a string');
-        }
-
         $name = \mb_strtolower($name);
 
         if (!isset($this->headerNames[$name])) {
@@ -109,7 +101,7 @@ public function getHeader($name): array
      *
      * @return string
      */
-    public function getHeaderLine($name): string
+    public function getHeaderLine(string $name): string
     {
         return \implode(', ', $this->getHeader($name));
     }
@@ -122,9 +114,9 @@ public function getHeaderLine($name): string
      *
      * @return self
      */
-    public function withHeader($name, $value): self
+    public function withHeader(string $name, $value): self
     {
-        if (!\is_string($name) || $name === '') {
+        if ($name === '') {
             throw new \InvalidArgumentException('Header name must be non-empty string');
         }
 
@@ -149,9 +141,9 @@ public function withHeader($name, $value): self
      *
      * @return self
      */
-    public function withAddedHeader($name, $value): self
+    public function withAddedHeader(string $name, $value): self
     {
-        if (!\is_string($name) || $name === '') {
+        if ($name === '') {
             throw new \InvalidArgumentException('Header name must be non-empty string');
         }
 
@@ -168,9 +160,9 @@ public function withAddedHeader($name, $value): self
      *
      * @return self
      */
-    public function withoutHeader($name): self
+    public function withoutHeader(string $name): self
     {
-        if (!\is_string($name) || $name === '') {
+        if ($name === '') {
             throw new \InvalidArgumentException('Header name must be non-empty string');
         }
 
@@ -240,8 +232,8 @@ protected function setHeaders(array $headers): void
     }
 
     /**
-     * @param string $header
-     * @param mixed  $values
+     * @param string|array $header
+     * @param mixed        $values
      *
      * @throws \InvalidArgumentException
      *
@@ -278,35 +270,35 @@ protected function validateAndTrimHeader($header, $values): array
     }
 
     /**
-     * Because of PHP 8.4.
+     * @param string $protocolVersion
      *
-     * @param        $string
-     * @param string $characters
+     * @throws \InvalidArgumentException
      *
      * @return string
      */
-    protected function trim($string, string $characters = " \n\r\t\v\0"): string
+    protected function validateProtocolVersion(string $protocolVersion): string
     {
-        if (\PHP_MAJOR_VERSION >= 8 && \PHP_MINOR_VERSION >= 4) {
-            return \mb_trim((string) $string, $characters);
+        if (!\in_array($protocolVersion, static::$validProtocols, true)) {
+            throw new \InvalidArgumentException('Protocol Version must be ' . \implode(' or ', static::$validProtocols));
         }
 
-        return \trim((string) $string, $characters);
+        return $protocolVersion;
     }
 
     /**
-     * @param string $protocolVersion
+     * Because of PHP 8.4.
      *
-     * @throws \InvalidArgumentException
+     * @param        $string
+     * @param string $characters
      *
      * @return string
      */
-    protected function validateProtocolVersion(string $protocolVersion): string
+    protected function trim($string, string $characters = " \n\r\t\v\0"): string
     {
-        if (!\in_array($protocolVersion, static::$validProtocols, true)) {
-            throw new \InvalidArgumentException('Protocol Version must be ' . \implode(' or ', static::$validProtocols));
+        if (\PHP_MAJOR_VERSION >= 8 && \PHP_MINOR_VERSION >= 4) {
+            return \mb_trim((string) $string, $characters);
         }
 
-        return $protocolVersion;
+        return \trim((string) $string, $characters);
     }
 }
diff --git a/src/Message/RequestTrait.php b/src/Message/RequestTrait.php
index b53db83..a625d8a 100644
--- a/src/Message/RequestTrait.php
+++ b/src/Message/RequestTrait.php
@@ -96,13 +96,13 @@ public function getRequestTarget(): string
     }
 
     /**
-     * @param $requestTarget
+     * @param string $requestTarget
      *
      * @throws \InvalidArgumentException
      *
      * @return self
      */
-    public function withRequestTarget($requestTarget): self
+    public function withRequestTarget(string $requestTarget): self
     {
         if (\preg_match('#\s#', $requestTarget)) {
             throw new \InvalidArgumentException('Invalid request target provided; cannot contain whitespace');
@@ -129,7 +129,7 @@ public function getMethod(): string
      *
      * @return self
      */
-    public function withMethod($method): self
+    public function withMethod(string $method): self
     {
         $method = $this->filterMethod($method);
 
@@ -155,12 +155,8 @@ public function getUri(): UriInterface
      *
      * @return self
      */
-    public function withUri(UriInterface $uri, $preserveHost = false): self
+    public function withUri(UriInterface $uri, bool $preserveHost = false): self
     {
-        if (!\is_bool($preserveHost)) {
-            throw new \InvalidArgumentException('Preserve Host must be a boolean');
-        }
-
         if ($this->uri === $uri) {
             return $this;
         }
@@ -182,12 +178,8 @@ public function withUri(UriInterface $uri, $preserveHost = false): self
      *
      * @return string
      */
-    protected function filterMethod($method): string
+    protected function filterMethod(string $method): string
     {
-        if (!\is_string($method)) {
-            throw new \InvalidArgumentException('Method must be a string');
-        }
-
         if (!\in_array($method, static::$methods, true)) {
             throw new \InvalidArgumentException(\sprintf('Method %s is invalid', $method));
         }
diff --git a/src/Message/Response.php b/src/Message/Response.php
index 6d11e20..8fc5067 100644
--- a/src/Message/Response.php
+++ b/src/Message/Response.php
@@ -233,12 +233,8 @@ public function getStatusCode(): int
      *
      * @return Response
      */
-    public function withStatus($code, $reasonPhrase = ''): self
+    public function withStatus(int $code, string $reasonPhrase = ''): self
     {
-        if (!\is_int($code)) {
-            throw new \InvalidArgumentException('Status code has to be an integer');
-        }
-
         if (!isset(static::PHRASES[$code])) {
             throw new \InvalidArgumentException('Status code has to be an integer between 100 and 799');
         }
diff --git a/src/Message/ServerRequest.php b/src/Message/ServerRequest.php
index dcdbaad..fcc81d9 100644
--- a/src/Message/ServerRequest.php
+++ b/src/Message/ServerRequest.php
@@ -182,12 +182,8 @@ public function getAttributes(): array
      *
      * @return mixed|null
      */
-    public function getAttribute($name, $default = null)
+    public function getAttribute(string $name, $default = null)
     {
-        if (!\is_string($name)) {
-            throw new \InvalidArgumentException('Name must be a string');
-        }
-
         if (!\array_key_exists($name, $this->attributes)) {
             return $default;
         }
@@ -203,12 +199,8 @@ public function getAttribute($name, $default = null)
      *
      * @return self
      */
-    public function withAttribute($name, $value): self
+    public function withAttribute(string $name, $value): self
     {
-        if (!\is_string($name)) {
-            throw new \InvalidArgumentException('Name must be a string');
-        }
-
         $new = clone $this;
         $new->attributes[$name] = $value;
 
@@ -222,12 +214,8 @@ public function withAttribute($name, $value): self
      *
      * @return self
      */
-    public function withoutAttribute($name): self
+    public function withoutAttribute(string $name): self
     {
-        if (!\is_string($name)) {
-            throw new \InvalidArgumentException('Name must be a string');
-        }
-
         if (!\array_key_exists($name, $this->attributes)) {
             return $this;
         }
diff --git a/src/Message/Stream.php b/src/Message/Stream.php
index bcdf355..b161067 100644
--- a/src/Message/Stream.php
+++ b/src/Message/Stream.php
@@ -162,16 +162,8 @@ public function isSeekable(): bool
      * @throws \InvalidArgumentException
      * @throws \RuntimeException
      */
-    public function seek($offset, $whence = \SEEK_SET): void
+    public function seek(int $offset, int $whence = \SEEK_SET): void
     {
-        if (!\is_int($offset)) {
-            throw new \InvalidArgumentException('Offset must be a int');
-        }
-
-        if (!\is_int($whence)) {
-            throw new \InvalidArgumentException('Whence must be a int');
-        }
-
         if (!$this->seekable) {
             throw new \RuntimeException('Stream is not seekable');
         }
@@ -208,12 +200,8 @@ public function isWritable(): bool
      *
      * @return int
      */
-    public function write($string)
+    public function write(string $string): int
     {
-        if (!\is_string($string)) {
-            throw new \InvalidArgumentException('Data must be a string');
-        }
-
         if (!$this->writable) {
             throw new \RuntimeException('Cannot write to a non-writable stream');
         }
@@ -241,19 +229,15 @@ public function isReadable(): bool
     }
 
     /**
-     * @param $length
+     * @param int $length
      *
      * @throws \InvalidArgumentException
      * @throws \RuntimeException
      *
      * @return string
      */
-    public function read($length): string
+    public function read(int $length): string
     {
-        if (!\is_int($length)) {
-            throw new \InvalidArgumentException('Length must be a int');
-        }
-
         if (!$this->readable) {
             throw new \RuntimeException('Cannot read from non-readable stream');
         }
@@ -318,14 +302,10 @@ public function getContents(): string
      *
      * @throws \InvalidArgumentException
      *
-     * @return array|null
+     * @return array|mixed|null
      */
-    public function getMetadata($key = null)
+    public function getMetadata(?string $key = null)
     {
-        if (!$this->isStringOrNull($key)) {
-            throw new \InvalidArgumentException('Key must be a string or NULL');
-        }
-
         if (!isset($this->stream)) {
             return $key ? null : [];
         }
@@ -428,14 +408,4 @@ public function __destruct()
     {
         $this->close();
     }
-
-    /**
-     * @param $param
-     *
-     * @return bool
-     */
-    protected function isStringOrNull($param): bool
-    {
-        return $param === null || \is_string($param);
-    }
 }
diff --git a/src/Message/UploadedFile.php b/src/Message/UploadedFile.php
index dd5be84..fa44ead 100644
--- a/src/Message/UploadedFile.php
+++ b/src/Message/UploadedFile.php
@@ -43,7 +43,7 @@ class UploadedFile implements UploadedFileInterface
 
     /**
      * @param StreamInterface|string|resource $streamOrFile
-     * @param int                             $size
+     * @param int|null                        $size
      * @param int                             $errorStatus
      * @param string|null                     $clientFilename
      * @param string|null                     $clientMediaType
@@ -52,10 +52,10 @@ class UploadedFile implements UploadedFileInterface
      */
     public function __construct(
         $streamOrFile,
-        $size,
-        $errorStatus,
-        $clientFilename = null,
-        $clientMediaType = null
+        ?int $size,
+        int $errorStatus,
+        ?string $clientFilename = null,
+        ?string $clientMediaType = null
     ) {
         $this->setError($errorStatus);
         $this->setSize($size);
@@ -90,7 +90,7 @@ public function getStream(): StreamInterface
      * @throws \InvalidArgumentException
      * @throws \RuntimeException
      */
-    public function moveTo($targetPath): void
+    public function moveTo(string $targetPath): void
     {
         $this->validateActive();
 
@@ -187,12 +187,8 @@ protected function setStreamOrFile($streamOrFile): void
      *
      * @throws \InvalidArgumentException
      */
-    protected function setError($error): void
+    protected function setError(int $error): void
     {
-        if (!\is_int($error)) {
-            throw new \InvalidArgumentException('Upload file error status must be an integer');
-        }
-
         if (!isset(static::ERRORS[$error])) {
             throw new \InvalidArgumentException('Invalid error status for UploadedFile');
         }
@@ -201,29 +197,15 @@ protected function setError($error): void
     }
 
     /**
-     * @param int $size
+     * @param int|null $size
      *
      * @throws \InvalidArgumentException
      */
-    protected function setSize($size): void
+    protected function setSize(?int $size): void
     {
-        if (!\is_int($size)) {
-            throw new \InvalidArgumentException('Upload file size must be an integer');
-        }
-
         $this->size = $size;
     }
 
-    /**
-     * @param $param
-     *
-     * @return bool
-     */
-    protected function isStringOrNull($param): bool
-    {
-        return $param === null || \is_string($param);
-    }
-
     /**
      * @param $param
      *
@@ -239,12 +221,8 @@ protected function isStringNotEmpty($param): bool
      *
      * @throws \InvalidArgumentException
      */
-    protected function setClientFilename($clientFilename): void
+    protected function setClientFilename(?string $clientFilename): void
     {
-        if (!$this->isStringOrNull($clientFilename)) {
-            throw new \InvalidArgumentException('Upload file client filename must be a string or null');
-        }
-
         $this->clientFilename = $clientFilename;
     }
 
@@ -253,12 +231,8 @@ protected function setClientFilename($clientFilename): void
      *
      * @throws \InvalidArgumentException
      */
-    protected function setClientMediaType($clientMediaType): void
+    protected function setClientMediaType(?string $clientMediaType): void
     {
-        if (!$this->isStringOrNull($clientMediaType)) {
-            throw new \InvalidArgumentException('Upload file client media type must be a string or null');
-        }
-
         $this->clientMediaType = $clientMediaType;
     }
 
diff --git a/src/Message/Uri.php b/src/Message/Uri.php
index 422e06e..7b75a23 100644
--- a/src/Message/Uri.php
+++ b/src/Message/Uri.php
@@ -139,7 +139,7 @@ public function getFragment(): string
      *
      * @return self
      */
-    public function withScheme($scheme): self
+    public function withScheme(string $scheme): self
     {
         $scheme = $this->filterScheme($scheme);
 
@@ -162,7 +162,7 @@ public function withScheme($scheme): self
      *
      * @return self
      */
-    public function withUserInfo($user, $password = null): self
+    public function withUserInfo(string $user, ?string $password = null): self
     {
         $info = $this->filterUser($user);
         $password = $this->filterPass($password);
@@ -188,7 +188,7 @@ public function withUserInfo($user, $password = null): self
      *
      * @return self
      */
-    public function withHost($host): self
+    public function withHost(string $host): self
     {
         $host = $this->filterHost($host);
 
@@ -209,7 +209,7 @@ public function withHost($host): self
      *
      * @return self
      */
-    public function withPort($port): self
+    public function withPort(?int $port): self
     {
         $port = $this->filterPort($port);
 
@@ -230,7 +230,7 @@ public function withPort($port): self
      *
      * @return self
      */
-    public function withPath($path): self
+    public function withPath(string $path): self
     {
         $path = $this->filterPath($path);
 
@@ -251,7 +251,7 @@ public function withPath($path): self
      *
      * @return self
      */
-    public function withQuery($query): self
+    public function withQuery(string $query): self
     {
         $query = $this->filterQueryAndFragment($query);
 
@@ -272,7 +272,7 @@ public function withQuery($query): self
      *
      * @return self
      */
-    public function withFragment($fragment): self
+    public function withFragment(string $fragment): self
     {
         $fragment = $this->filterQueryAndFragment($fragment);
 
@@ -401,23 +401,6 @@ protected static function createUriString(
         return $uri;
     }
 
-    /**
-     * Because of PHP 8.4.
-     *
-     * @param        $string
-     * @param string $characters
-     *
-     * @return string
-     */
-    protected static function ltrim($string, string $characters = " \n\r\t\v\0"): string
-    {
-        if (\PHP_MAJOR_VERSION >= 8 && \PHP_MINOR_VERSION >= 4) {
-            return \mb_ltrim((string) $string, $characters);
-        }
-
-        return \ltrim((string) $string, $characters);
-    }
-
     /**
      * @param string $scheme
      * @param int    $port
@@ -436,12 +419,8 @@ protected static function isNonStandardPort(string $scheme, int $port): bool
      *
      * @return string
      */
-    protected function filterScheme($scheme): string
+    protected function filterScheme(string $scheme): string
     {
-        if (!\is_string($scheme)) {
-            throw new \InvalidArgumentException('Scheme must be a string');
-        }
-
         return \mb_strtolower($scheme);
     }
 
@@ -452,12 +431,8 @@ protected function filterScheme($scheme): string
      *
      * @return string
      */
-    protected function filterUser($user): string
+    protected function filterUser(string $user): string
     {
-        if (!\is_string($user)) {
-            throw new \InvalidArgumentException('User must be a string');
-        }
-
         return $user;
     }
 
@@ -468,12 +443,8 @@ protected function filterUser($user): string
      *
      * @return string
      */
-    protected function filterPass($pass): ?string
+    protected function filterPass(?string $pass): ?string
     {
-        if ($pass !== null && !\is_string($pass)) {
-            throw new \InvalidArgumentException('Password must be a string or NULL');
-        }
-
         return $pass;
     }
 
@@ -484,12 +455,8 @@ protected function filterPass($pass): ?string
      *
      * @return string
      */
-    protected function filterHost($host): string
+    protected function filterHost(string $host): string
     {
-        if (!\is_string($host)) {
-            throw new \InvalidArgumentException('Host must be a string');
-        }
-
         return \mb_strtolower($host);
     }
 
@@ -500,13 +467,12 @@ protected function filterHost($host): string
      *
      * @return int|null
      */
-    protected function filterPort($port): ?int
+    protected function filterPort(?int $port): ?int
     {
         if ($port === null) {
             return null;
         }
 
-        $port = (int) $port;
         if ($port < 1 || $port > 65535) {
             throw new \InvalidArgumentException(\sprintf('Invalid port: %d. Must be between 1 and 65535', $port));
         }
@@ -525,12 +491,8 @@ protected function filterPort($port): ?int
      *
      * @return string
      */
-    protected function filterPath($path): string
+    protected function filterPath(string $path): string
     {
-        if (!\is_string($path)) {
-            throw new \InvalidArgumentException('Path must be a string');
-        }
-
         return \preg_replace_callback(
             static::getPatternForFilteringPath(),
             [__CLASS__, 'rawurlencodeMatchZero'],
@@ -545,12 +507,8 @@ protected function filterPath($path): string
      *
      * @return string
      */
-    protected function filterQueryAndFragment($str): string
+    protected function filterQueryAndFragment(string $str): string
     {
-        if (!\is_string($str)) {
-            throw new \InvalidArgumentException('Query and fragment must be a string');
-        }
-
         return \preg_replace_callback(
             static::getPatternForFilteringQueryAndFragment(),
             [__CLASS__, 'rawurlencodeMatchZero'],
@@ -583,4 +541,21 @@ protected static function getPatternForFilteringQueryAndFragment(): string
     {
         return '/(?:[^' . static::CHAR_UNRESERVED . static::CHAR_SUB_DELIMS . '%:@\/\?]++|%(?![A-Fa-f0-9]{2}))/';
     }
+
+    /**
+     * Because of PHP 8.4.
+     *
+     * @param        $string
+     * @param string $characters
+     *
+     * @return string
+     */
+    protected static function ltrim($string, string $characters = " \n\r\t\v\0"): string
+    {
+        if (\PHP_MAJOR_VERSION >= 8 && \PHP_MINOR_VERSION >= 4) {
+            return \mb_ltrim((string) $string, $characters);
+        }
+
+        return \ltrim((string) $string, $characters);
+    }
 }
diff --git a/src/Psr/Message/MessageInterface.php b/src/Psr/Message/MessageInterface.php
index 40108a2..a83c985 100644
--- a/src/Psr/Message/MessageInterface.php
+++ b/src/Psr/Message/MessageInterface.php
@@ -23,7 +23,7 @@ interface MessageInterface
      *
      * @return string HTTP protocol version.
      */
-    public function getProtocolVersion();
+    public function getProtocolVersion(): string;
 
     /**
      * Return an instance with the specified HTTP protocol version.
@@ -38,7 +38,7 @@ public function getProtocolVersion();
      * @param string $version HTTP protocol version
      * @return static
      */
-    public function withProtocolVersion($version);
+    public function withProtocolVersion(string $version): MessageInterface;
 
     /**
      * Retrieves all message header values.
@@ -65,7 +65,7 @@ public function withProtocolVersion($version);
      *     key MUST be a header name, and each value MUST be an array of strings
      *     for that header.
      */
-    public function getHeaders();
+    public function getHeaders(): array;
 
     /**
      * Checks if a header exists by the given case-insensitive name.
@@ -75,7 +75,7 @@ public function getHeaders();
      *     name using a case-insensitive string comparison. Returns false if
      *     no matching header name is found in the message.
      */
-    public function hasHeader($name);
+    public function hasHeader(string $name): bool;
 
     /**
      * Retrieves a message header value by the given case-insensitive name.
@@ -91,7 +91,7 @@ public function hasHeader($name);
      *    header. If the header does not appear in the message, this method MUST
      *    return an empty array.
      */
-    public function getHeader($name);
+    public function getHeader(string $name): array;
 
     /**
      * Retrieves a comma-separated string of the values for a single header.
@@ -112,7 +112,7 @@ public function getHeader($name);
      *    concatenated together using a comma. If the header does not appear in
      *    the message, this method MUST return an empty string.
      */
-    public function getHeaderLine($name);
+    public function getHeaderLine(string $name): string;
 
     /**
      * Return an instance with the provided value replacing the specified header.
@@ -129,7 +129,7 @@ public function getHeaderLine($name);
      * @return static
      * @throws \InvalidArgumentException for invalid header names or values.
      */
-    public function withHeader($name, $value);
+    public function withHeader(string $name, $value): MessageInterface;
 
     /**
      * Return an instance with the specified header appended with the given value.
@@ -147,7 +147,7 @@ public function withHeader($name, $value);
      * @return static
      * @throws \InvalidArgumentException for invalid header names or values.
      */
-    public function withAddedHeader($name, $value);
+    public function withAddedHeader(string $name, $value): MessageInterface;
 
     /**
      * Return an instance without the specified header.
@@ -161,14 +161,14 @@ public function withAddedHeader($name, $value);
      * @param string $name Case-insensitive header field name to remove.
      * @return static
      */
-    public function withoutHeader($name);
+    public function withoutHeader(string $name): MessageInterface;
 
     /**
      * Gets the body of the message.
      *
      * @return StreamInterface Returns the body as a stream.
      */
-    public function getBody();
+    public function getBody(): StreamInterface;
 
     /**
      * Return an instance with the specified message body.
@@ -183,5 +183,5 @@ public function getBody();
      * @return static
      * @throws \InvalidArgumentException When the body is not valid.
      */
-    public function withBody(StreamInterface $body);
-}
\ No newline at end of file
+    public function withBody(StreamInterface $body): MessageInterface;
+}
diff --git a/src/Psr/Message/RequestInterface.php b/src/Psr/Message/RequestInterface.php
index 5b1c9c0..33f85e5 100644
--- a/src/Psr/Message/RequestInterface.php
+++ b/src/Psr/Message/RequestInterface.php
@@ -39,7 +39,7 @@ interface RequestInterface extends MessageInterface
      *
      * @return string
      */
-    public function getRequestTarget();
+    public function getRequestTarget(): string;
 
     /**
      * Return an instance with the specific request-target.
@@ -55,17 +55,18 @@ public function getRequestTarget();
      *
      * @link http://tools.ietf.org/html/rfc7230#section-5.3 (for the various
      *     request-target forms allowed in request messages)
-     * @param mixed $requestTarget
+     * @param string $requestTarget
      * @return static
      */
-    public function withRequestTarget($requestTarget);
+    public function withRequestTarget(string $requestTarget): RequestInterface;
+
 
     /**
      * Retrieves the HTTP method of the request.
      *
      * @return string Returns the request method.
      */
-    public function getMethod();
+    public function getMethod(): string;
 
     /**
      * Return an instance with the provided HTTP method.
@@ -82,7 +83,7 @@ public function getMethod();
      * @return static
      * @throws \InvalidArgumentException for invalid HTTP methods.
      */
-    public function withMethod($method);
+    public function withMethod(string $method): RequestInterface;
 
     /**
      * Retrieves the URI instance.
@@ -93,7 +94,7 @@ public function withMethod($method);
      * @return UriInterface Returns a UriInterface instance
      *     representing the URI of the request.
      */
-    public function getUri();
+    public function getUri(): UriInterface;
 
     /**
      * Returns an instance with the provided URI.
@@ -125,5 +126,5 @@ public function getUri();
      * @param bool $preserveHost Preserve the original state of the Host header.
      * @return static
      */
-    public function withUri(UriInterface $uri, $preserveHost = false);
-}
\ No newline at end of file
+    public function withUri(UriInterface $uri, bool $preserveHost = false): RequestInterface;
+}
diff --git a/src/Psr/Message/ResponseInterface.php b/src/Psr/Message/ResponseInterface.php
index 5f7344b..e9299a9 100644
--- a/src/Psr/Message/ResponseInterface.php
+++ b/src/Psr/Message/ResponseInterface.php
@@ -27,7 +27,7 @@ interface ResponseInterface extends MessageInterface
      *
      * @return int Status code.
      */
-    public function getStatusCode();
+    public function getStatusCode(): int;
 
     /**
      * Return an instance with the specified status code and, optionally, reason phrase.
@@ -49,7 +49,7 @@ public function getStatusCode();
      * @return static
      * @throws \InvalidArgumentException For invalid status code arguments.
      */
-    public function withStatus($code, $reasonPhrase = '');
+    public function withStatus(int $code, string $reasonPhrase = ''): ResponseInterface;
 
     /**
      * Gets the response reason phrase associated with the status code.
@@ -64,5 +64,5 @@ public function withStatus($code, $reasonPhrase = '');
      * @link http://www.iana.org/assignments/http-status-codes/http-status-codes.xhtml
      * @return string Reason phrase; must return an empty string if none present.
      */
-    public function getReasonPhrase();
-}
\ No newline at end of file
+    public function getReasonPhrase(): string;
+}
diff --git a/src/Psr/Message/ServerRequestInterface.php b/src/Psr/Message/ServerRequestInterface.php
index 42baf11..8625d0e 100644
--- a/src/Psr/Message/ServerRequestInterface.php
+++ b/src/Psr/Message/ServerRequestInterface.php
@@ -51,7 +51,7 @@ interface ServerRequestInterface extends RequestInterface
      *
      * @return array
      */
-    public function getServerParams();
+    public function getServerParams(): array;
 
     /**
      * Retrieve cookies.
@@ -63,7 +63,7 @@ public function getServerParams();
      *
      * @return array
      */
-    public function getCookieParams();
+    public function getCookieParams(): array;
 
     /**
      * Return an instance with the specified cookies.
@@ -82,7 +82,7 @@ public function getCookieParams();
      * @param array $cookies Array of key/value pairs representing cookies.
      * @return static
      */
-    public function withCookieParams(array $cookies);
+    public function withCookieParams(array $cookies): ServerRequestInterface;
 
     /**
      * Retrieve query string arguments.
@@ -96,7 +96,7 @@ public function withCookieParams(array $cookies);
      *
      * @return array
      */
-    public function getQueryParams();
+    public function getQueryParams(): array;
 
     /**
      * Return an instance with the specified query string arguments.
@@ -120,7 +120,7 @@ public function getQueryParams();
      *     $_GET.
      * @return static
      */
-    public function withQueryParams(array $query);
+    public function withQueryParams(array $query): ServerRequestInterface;
 
     /**
      * Retrieve normalized file upload data.
@@ -134,7 +134,7 @@ public function withQueryParams(array $query);
      * @return array An array tree of UploadedFileInterface instances; an empty
      *     array MUST be returned if no data is present.
      */
-    public function getUploadedFiles();
+    public function getUploadedFiles(): array;
 
     /**
      * Create a new instance with the specified uploaded files.
@@ -147,7 +147,7 @@ public function getUploadedFiles();
      * @return static
      * @throws \InvalidArgumentException if an invalid structure is provided.
      */
-    public function withUploadedFiles(array $uploadedFiles);
+    public function withUploadedFiles(array $uploadedFiles): ServerRequestInterface;
 
     /**
      * Retrieve any parameters provided in the request body.
@@ -194,7 +194,7 @@ public function getParsedBody();
      * @throws \InvalidArgumentException if an unsupported argument type is
      *     provided.
      */
-    public function withParsedBody($data);
+    public function withParsedBody($data): ServerRequestInterface;
 
     /**
      * Retrieve attributes derived from the request.
@@ -207,7 +207,7 @@ public function withParsedBody($data);
      *
      * @return array Attributes derived from the request.
      */
-    public function getAttributes();
+    public function getAttributes(): array;
 
     /**
      * Retrieve a single derived request attribute.
@@ -224,7 +224,7 @@ public function getAttributes();
      * @param mixed $default Default value to return if the attribute does not exist.
      * @return mixed
      */
-    public function getAttribute($name, $default = null);
+    public function getAttribute(string $name, $default = null);
 
     /**
      * Return an instance with the specified derived request attribute.
@@ -241,7 +241,7 @@ public function getAttribute($name, $default = null);
      * @param mixed $value The value of the attribute.
      * @return static
      */
-    public function withAttribute($name, $value);
+    public function withAttribute(string $name, $value): ServerRequestInterface;
 
     /**
      * Return an instance that removes the specified derived request attribute.
@@ -257,5 +257,5 @@ public function withAttribute($name, $value);
      * @param string $name The attribute name.
      * @return static
      */
-    public function withoutAttribute($name);
-}
\ No newline at end of file
+    public function withoutAttribute(string $name): ServerRequestInterface;
+}
diff --git a/src/Psr/Message/StreamInterface.php b/src/Psr/Message/StreamInterface.php
index c7b3368..a62aabb 100644
--- a/src/Psr/Message/StreamInterface.php
+++ b/src/Psr/Message/StreamInterface.php
@@ -25,14 +25,14 @@ interface StreamInterface
      * @see http://php.net/manual/en/language.oop5.magic.php#object.tostring
      * @return string
      */
-    public function __toString();
+    public function __toString(): string;
 
     /**
      * Closes the stream and any underlying resources.
      *
      * @return void
      */
-    public function close();
+    public function close(): void;
 
     /**
      * Separates any underlying resources from the stream.
@@ -48,7 +48,7 @@ public function detach();
      *
      * @return int|null Returns the size in bytes if known, or null if unknown.
      */
-    public function getSize();
+    public function getSize(): ?int;
 
     /**
      * Returns the current position of the file read/write pointer
@@ -56,21 +56,21 @@ public function getSize();
      * @return int Position of the file pointer
      * @throws \RuntimeException on error.
      */
-    public function tell();
+    public function tell(): int;
 
     /**
      * Returns true if the stream is at the end of the stream.
      *
      * @return bool
      */
-    public function eof();
+    public function eof(): bool;
 
     /**
      * Returns whether or not the stream is seekable.
      *
      * @return bool
      */
-    public function isSeekable();
+    public function isSeekable(): bool;
 
     /**
      * Seek to a position in the stream.
@@ -84,7 +84,7 @@ public function isSeekable();
      *     SEEK_END: Set position to end-of-stream plus offset.
      * @throws \RuntimeException on failure.
      */
-    public function seek($offset, $whence = SEEK_SET);
+    public function seek(int $offset, int $whence = SEEK_SET): void;
 
     /**
      * Seek to the beginning of the stream.
@@ -96,14 +96,14 @@ public function seek($offset, $whence = SEEK_SET);
      * @link http://www.php.net/manual/en/function.fseek.php
      * @throws \RuntimeException on failure.
      */
-    public function rewind();
+    public function rewind(): void;
 
     /**
      * Returns whether or not the stream is writable.
      *
      * @return bool
      */
-    public function isWritable();
+    public function isWritable(): bool;
 
     /**
      * Write data to the stream.
@@ -112,14 +112,14 @@ public function isWritable();
      * @return int Returns the number of bytes written to the stream.
      * @throws \RuntimeException on failure.
      */
-    public function write($string);
+    public function write(string $string): int;
 
     /**
      * Returns whether or not the stream is readable.
      *
      * @return bool
      */
-    public function isReadable();
+    public function isReadable(): bool;
 
     /**
      * Read data from the stream.
@@ -131,7 +131,7 @@ public function isReadable();
      *     if no bytes are available.
      * @throws \RuntimeException if an error occurs.
      */
-    public function read($length);
+    public function read(int $length): string;
 
     /**
      * Returns the remaining contents in a string
@@ -140,7 +140,7 @@ public function read($length);
      * @throws \RuntimeException if unable to read or an error occurs while
      *     reading.
      */
-    public function getContents();
+    public function getContents(): string;
 
     /**
      * Get stream metadata as an associative array or retrieve a specific key.
@@ -149,10 +149,10 @@ public function getContents();
      * stream_get_meta_data() function.
      *
      * @link http://php.net/manual/en/function.stream-get-meta-data.php
-     * @param string $key Specific metadata to retrieve.
+     * @param string|null $key Specific metadata to retrieve.
      * @return array|mixed|null Returns an associative array if no key is
      *     provided. Returns a specific key value if a key is provided and the
      *     value is found, or null if the key is not found.
      */
-    public function getMetadata($key = null);
-}
\ No newline at end of file
+    public function getMetadata(?string $key = null);
+}
diff --git a/src/Psr/Message/UploadedFileFactoryInterface.php b/src/Psr/Message/UploadedFileFactoryInterface.php
index 03270e3..d7adbf0 100644
--- a/src/Psr/Message/UploadedFileFactoryInterface.php
+++ b/src/Psr/Message/UploadedFileFactoryInterface.php
@@ -15,10 +15,10 @@ interface UploadedFileFactoryInterface
      *
      * @param StreamInterface $stream Underlying stream representing the
      *     uploaded file content.
-     * @param int $size in bytes
+     * @param int|null $size in bytes
      * @param int $error PHP file upload error
-     * @param string $clientFilename Filename as provided by the client, if any.
-     * @param string $clientMediaType Media type as provided by the client, if any.
+     * @param string|null $clientFilename Filename as provided by the client, if any.
+     * @param string|null $clientMediaType Media type as provided by the client, if any.
      *
      * @return UploadedFileInterface
      *
@@ -26,9 +26,9 @@ interface UploadedFileFactoryInterface
      */
     public function createUploadedFile(
         StreamInterface $stream,
-        int $size = null,
+        ?int $size = null,
         int $error = \UPLOAD_ERR_OK,
-        string $clientFilename = null,
-        string $clientMediaType = null
+        ?string $clientFilename = null,
+        ?string $clientMediaType = null
     ): UploadedFileInterface;
-}
\ No newline at end of file
+}
diff --git a/src/Psr/Message/UploadedFileInterface.php b/src/Psr/Message/UploadedFileInterface.php
index eba5756..f13ed10 100644
--- a/src/Psr/Message/UploadedFileInterface.php
+++ b/src/Psr/Message/UploadedFileInterface.php
@@ -28,7 +28,7 @@ interface UploadedFileInterface
      * @throws \RuntimeException in cases when no stream is available or can be
      *     created.
      */
-    public function getStream();
+    public function getStream(): StreamInterface;
 
     /**
      * Move the uploaded file to a new location.
@@ -62,7 +62,7 @@ public function getStream();
      * @throws \RuntimeException on any error during the move operation, or on
      *     the second or subsequent call to the method.
      */
-    public function moveTo($targetPath);
+    public function moveTo(string $targetPath): void;
 
     /**
      * Retrieve the file size.
@@ -73,7 +73,7 @@ public function moveTo($targetPath);
      *
      * @return int|null The file size in bytes or null if unknown.
      */
-    public function getSize();
+    public function getSize(): ?int;
 
     /**
      * Retrieve the error associated with the uploaded file.
@@ -89,7 +89,7 @@ public function getSize();
      * @see http://php.net/manual/en/features.file-upload.errors.php
      * @return int One of PHP's UPLOAD_ERR_XXX constants.
      */
-    public function getError();
+    public function getError(): int;
 
     /**
      * Retrieve the filename sent by the client.
@@ -104,7 +104,7 @@ public function getError();
      * @return string|null The filename sent by the client or null if none
      *     was provided.
      */
-    public function getClientFilename();
+    public function getClientFilename(): ?string;
 
     /**
      * Retrieve the media type sent by the client.
@@ -119,5 +119,5 @@ public function getClientFilename();
      * @return string|null The media type sent by the client or null if none
      *     was provided.
      */
-    public function getClientMediaType();
-}
\ No newline at end of file
+    public function getClientMediaType(): ?string;
+}
diff --git a/src/Psr/Message/UriInterface.php b/src/Psr/Message/UriInterface.php
index 6adb8fc..15e2cf2 100644
--- a/src/Psr/Message/UriInterface.php
+++ b/src/Psr/Message/UriInterface.php
@@ -1,4 +1,5 @@
 <?php
+
 namespace Psr\Http\Message;
 
 /**
@@ -37,7 +38,7 @@ interface UriInterface
      * @see https://tools.ietf.org/html/rfc3986#section-3.1
      * @return string The URI scheme.
      */
-    public function getScheme();
+    public function getScheme(): string;
 
     /**
      * Retrieve the authority component of the URI.
@@ -57,7 +58,7 @@ public function getScheme();
      * @see https://tools.ietf.org/html/rfc3986#section-3.2
      * @return string The URI authority, in "[user-info@]host[:port]" format.
      */
-    public function getAuthority();
+    public function getAuthority(): string;
 
     /**
      * Retrieve the user information component of the URI.
@@ -74,7 +75,7 @@ public function getAuthority();
      *
      * @return string The URI user information, in "username[:password]" format.
      */
-    public function getUserInfo();
+    public function getUserInfo(): string;
 
     /**
      * Retrieve the host component of the URI.
@@ -87,7 +88,7 @@ public function getUserInfo();
      * @see http://tools.ietf.org/html/rfc3986#section-3.2.2
      * @return string The URI host.
      */
-    public function getHost();
+    public function getHost(): string;
 
     /**
      * Retrieve the port component of the URI.
@@ -104,7 +105,7 @@ public function getHost();
      *
      * @return null|int The URI port.
      */
-    public function getPort();
+    public function getPort(): ?int;
 
     /**
      * Retrieve the path component of the URI.
@@ -131,7 +132,7 @@ public function getPort();
      * @see https://tools.ietf.org/html/rfc3986#section-3.3
      * @return string The URI path.
      */
-    public function getPath();
+    public function getPath(): string;
 
     /**
      * Retrieve the query string of the URI.
@@ -153,7 +154,7 @@ public function getPath();
      * @see https://tools.ietf.org/html/rfc3986#section-3.4
      * @return string The URI query string.
      */
-    public function getQuery();
+    public function getQuery(): string;
 
     /**
      * Retrieve the fragment component of the URI.
@@ -171,7 +172,7 @@ public function getQuery();
      * @see https://tools.ietf.org/html/rfc3986#section-3.5
      * @return string The URI fragment.
      */
-    public function getFragment();
+    public function getFragment(): string;
 
     /**
      * Return an instance with the specified scheme.
@@ -188,7 +189,7 @@ public function getFragment();
      * @return static A new instance with the specified scheme.
      * @throws \InvalidArgumentException for invalid or unsupported schemes.
      */
-    public function withScheme($scheme);
+    public function withScheme(string $scheme): UriInterface;
 
     /**
      * Return an instance with the specified user information.
@@ -204,7 +205,7 @@ public function withScheme($scheme);
      * @param null|string $password The password associated with $user.
      * @return static A new instance with the specified user information.
      */
-    public function withUserInfo($user, $password = null);
+    public function withUserInfo(string $user, ?string $password = null): UriInterface;
 
     /**
      * Return an instance with the specified host.
@@ -218,7 +219,7 @@ public function withUserInfo($user, $password = null);
      * @return static A new instance with the specified host.
      * @throws \InvalidArgumentException for invalid hostnames.
      */
-    public function withHost($host);
+    public function withHost(string $host): UriInterface;
 
     /**
      * Return an instance with the specified port.
@@ -237,7 +238,7 @@ public function withHost($host);
      * @return static A new instance with the specified port.
      * @throws \InvalidArgumentException for invalid ports.
      */
-    public function withPort($port);
+    public function withPort(?int $port): UriInterface;
 
     /**
      * Return an instance with the specified path.
@@ -261,7 +262,7 @@ public function withPort($port);
      * @return static A new instance with the specified path.
      * @throws \InvalidArgumentException for invalid paths.
      */
-    public function withPath($path);
+    public function withPath(string $path): UriInterface;
 
     /**
      * Return an instance with the specified query string.
@@ -278,7 +279,7 @@ public function withPath($path);
      * @return static A new instance with the specified query string.
      * @throws \InvalidArgumentException for invalid query strings.
      */
-    public function withQuery($query);
+    public function withQuery(string $query): UriInterface;
 
     /**
      * Return an instance with the specified URI fragment.
@@ -294,7 +295,7 @@ public function withQuery($query);
      * @param string $fragment The fragment to use with the new instance.
      * @return static A new instance with the specified fragment.
      */
-    public function withFragment($fragment);
+    public function withFragment(string $fragment): UriInterface;
 
     /**
      * Return the string representation as a URI reference.
@@ -319,5 +320,5 @@ public function withFragment($fragment);
      * @see http://tools.ietf.org/html/rfc3986#section-4.1
      * @return string
      */
-    public function __toString();
-}
\ No newline at end of file
+    public function __toString(): string;
+}
diff --git a/src/Psr/Server/MiddlewareInterface.php b/src/Psr/Server/MiddlewareInterface.php
index 0393475..b4b38b2 100644
--- a/src/Psr/Server/MiddlewareInterface.php
+++ b/src/Psr/Server/MiddlewareInterface.php
@@ -27,4 +27,4 @@ interface MiddlewareInterface
      * @return ResponseInterface
      */
     public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface;
-}
\ No newline at end of file
+}
diff --git a/src/Psr/Server/RequestHandlerInterface.php b/src/Psr/Server/RequestHandlerInterface.php
index 7e38f1f..742d5ae 100644
--- a/src/Psr/Server/RequestHandlerInterface.php
+++ b/src/Psr/Server/RequestHandlerInterface.php
@@ -8,7 +8,7 @@
 /**
  * Handles a server request and produces a response.
  *
- * An HTTP request handler process an HTTP request in order to produce an
+ * An HTTP request handler processes an HTTP request in order to produce an
  * HTTP response.
  */
 interface RequestHandlerInterface
@@ -23,4 +23,4 @@ interface RequestHandlerInterface
      * @return ResponseInterface
      */
     public function handle(ServerRequestInterface $request): ResponseInterface;
-}
\ No newline at end of file
+}
diff --git a/tests/RequestTest.php b/tests/RequestTest.php
index 7b0a844..ba18548 100644
--- a/tests/RequestTest.php
+++ b/tests/RequestTest.php
@@ -189,24 +189,6 @@ public function testWithMethod(): void
         static::assertSame('PATCH', $r->getMethod());
     }
 
-    public function testWithUriPreserveHostMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Preserve Host must be a boolean');
-
-        $r = new Request('GET', 'https://foo.com:8124/bar');
-        $r->withUri(new Uri(), null);
-    }
-
-    public function testWithMethodMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Method must be a string');
-
-        $r = new Request('GET', 'https://foo.com:8124/bar');
-        $r->withMethod(null);
-    }
-
     public function testWithMethodMustBeValidMethod(): void
     {
         $this->expectException(\InvalidArgumentException::class);
diff --git a/tests/ResponseTest.php b/tests/ResponseTest.php
index 899cfb3..cd61609 100644
--- a/tests/ResponseTest.php
+++ b/tests/ResponseTest.php
@@ -46,17 +46,6 @@ public function testConstructStatusCantBeNumericString(): void
         new Response('-404.4');
     }
 
-    public function testWithStatusCantBeNumericString(): void
-    {
-        $r = new Response(404);
-        static::assertSame(404, $r->getStatusCode());
-        static::assertSame('Not Found', $r->getReasonPhrase());
-
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Status code has to be an integer');
-        $r->withStatus('201');
-    }
-
     public function testCanConstructWithHeaders(): void
     {
         $r = new Response(200, ['Foo' => 'Bar']);
@@ -131,6 +120,15 @@ public function testRaiseExceptionConstructWithProtocolVersion(): void
         new Response(200, [], null, '1000');
     }
 
+    public function testRaiseWithInvalidStatusCode(): void
+    {
+        $r = new Response();
+
+        $this->expectException(\InvalidArgumentException::class);
+        $this->expectExceptionMessage('Status code has to be an integer between 100 and 799');
+        $r->withStatus(1);
+    }
+
     public function testWithStatusCodeAndNoReason(): void
     {
         $r = (new Response())->withStatus(201);
@@ -269,33 +267,6 @@ public function trimmedHeaderValues(): array
         ];
     }
 
-    public function testHasHeaderMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Header name must be a string');
-
-        $r = new Response();
-        static::assertSame($r, $r->hasHeader(null));
-    }
-
-    public function testGetHeaderMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Header name must be a string');
-
-        $r = new Response();
-        static::assertSame($r, $r->getHeader(null));
-    }
-
-    public function testGetHeaderLineMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Header name must be a string');
-
-        $r = new Response();
-        static::assertSame($r, $r->getHeaderLine(null));
-    }
-
     public function testWithHeaderNameMustHaveCorrectType(): void
     {
         $this->expectException(\InvalidArgumentException::class);
@@ -389,24 +360,6 @@ public function testHeaderValuesAreTrimmed(Response $r): void
         static::assertSame(['Foo'], $r->getHeader('OWS'));
     }
 
-    public function testWithStatusCodeMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Status code has to be an integer');
-
-        $r = new Response();
-        $r->withStatus([]);
-    }
-
-    public function testWithStatusReasonPhraseMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Status code has to be an integer between 100 and 799');
-
-        $r = new Response();
-        $r->withStatus(9, []);
-    }
-
     /**
      * @runInSeparateProcess
      */
diff --git a/tests/ServerRequestTest.php b/tests/ServerRequestTest.php
index 4ef0aac..ea987bf 100644
--- a/tests/ServerRequestTest.php
+++ b/tests/ServerRequestTest.php
@@ -546,30 +546,6 @@ public function testNullAttribute(): void
         static::assertSame('different-default', $requestWithoutAttribute->getAttribute('name', 'different-default'));
     }
 
-    public function testGetAttributeMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Name must be a string');
-
-        (new ServerRequest('GET', '/'))->getAttribute([]);
-    }
-
-    public function testWithAttributeMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Name must be a string');
-
-        (new ServerRequest('GET', '/'))->withAttribute([], null);
-    }
-
-    public function testWithoutAttributeMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Name must be a string');
-
-        (new ServerRequest('GET', '/'))->withoutAttribute([]);
-    }
-
     public function testWithParsedBodyMustHaveCorrectType(): void
     {
         $this->expectException(\InvalidArgumentException::class);
diff --git a/tests/StreamTest.php b/tests/StreamTest.php
index f40902b..7844f9b 100644
--- a/tests/StreamTest.php
+++ b/tests/StreamTest.php
@@ -179,26 +179,6 @@ public function testCloseClearProperties(): void
         static::assertNull($stream->getMetadata('key'));
     }
 
-    public function testSeekRaiseExceptionOffset(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Offset must be a int');
-
-        $handle = \fopen('php://temp', 'w+');
-        $stream = Stream::create($handle);
-        $stream->seek('string');
-    }
-
-    public function testSeekRaiseExceptionWhence(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Whence must be a int');
-
-        $handle = \fopen('php://temp', 'w+');
-        $stream = Stream::create($handle);
-        $stream->seek(1, 'string');
-    }
-
     public function testSeekRaiseExceptionUnableToSeek(): void
     {
         $this->expectException(\RuntimeException::class);
@@ -209,36 +189,6 @@ public function testSeekRaiseExceptionUnableToSeek(): void
         $stream->seek(1, 90909090);
     }
 
-    public function testWriteRaiseExceptionData(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Data must be a string');
-
-        $handle = \fopen('php://temp', 'w+');
-        $stream = Stream::create($handle);
-        $stream->write(0);
-    }
-
-    public function testReadRaiseExceptionLength(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Length must be a int');
-
-        $handle = \fopen('php://temp', 'w+');
-        $stream = Stream::create($handle);
-        $stream->read('string');
-    }
-
-    public function testGetMetadataRaiseExceptionKey(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Key must be a string or NULL');
-
-        $handle = \fopen('php://temp', 'w+');
-        $stream = Stream::create($handle);
-        $stream->getMetadata(45);
-    }
-
     public function testGetMetadataKeyNonExist(): void
     {
         $handle = \fopen('php://temp', 'w+');
diff --git a/tests/UploadedFileTest.php b/tests/UploadedFileTest.php
index 8a7054c..c109f6d 100644
--- a/tests/UploadedFileTest.php
+++ b/tests/UploadedFileTest.php
@@ -50,39 +50,9 @@ public function testRaisesExceptionOnInvalidStreamOrFile($streamOrFile): void
         new UploadedFile($streamOrFile, 0, \UPLOAD_ERR_OK);
     }
 
-    public function invalidSizes(): array
-    {
-        return [
-            'null'   => [null],
-            'float'  => [1.1],
-            'array'  => [[1]],
-            'object' => [(object) [1]],
-        ];
-    }
-
-    /**
-     * @dataProvider invalidSizes
-     *
-     * @param $size
-     */
-    public function testRaisesExceptionOnInvalidSize($size): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('size');
-
-        new UploadedFile(\fopen('php://temp', 'wb+'), $size, \UPLOAD_ERR_OK);
-    }
-
     public function invalidErrorStatuses(): array
     {
         return [
-            'null'     => [null],
-            'true'     => [true],
-            'false'    => [false],
-            'float'    => [1.1],
-            'string'   => ['1'],
-            'array'    => [[1]],
-            'object'   => [(object) [1]],
             'negative' => [-1],
             'too-big'  => [9],
         ];
@@ -101,44 +71,6 @@ public function testRaisesExceptionOnInvalidErrorStatus($status): void
         new UploadedFile(\fopen('php://temp', 'wb+'), 0, $status);
     }
 
-    public function invalidFilenamesAndMediaTypes(): array
-    {
-        return [
-            'true'   => [true],
-            'false'  => [false],
-            'int'    => [1],
-            'float'  => [1.1],
-            'array'  => [['string']],
-            'object' => [(object) ['string']],
-        ];
-    }
-
-    /**
-     * @dataProvider invalidFilenamesAndMediaTypes
-     *
-     * @param $filename
-     */
-    public function testRaisesExceptionOnInvalidClientFilename($filename): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('filename');
-
-        new UploadedFile(\fopen('php://temp', 'wb+'), 0, \UPLOAD_ERR_OK, $filename);
-    }
-
-    /**
-     * @dataProvider invalidFilenamesAndMediaTypes
-     *
-     * @param $mediaType
-     */
-    public function testRaisesExceptionOnInvalidClientMediaType($mediaType): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('media type');
-
-        new UploadedFile(\fopen('php://temp', 'wb+'), 0, \UPLOAD_ERR_OK, 'foobar.baz', $mediaType);
-    }
-
     public function testGetStreamWithFile(): void
     {
         $stream = Stream::createFromFile(__DIR__ . \DIRECTORY_SEPARATOR . 'noise.jpg');
@@ -184,14 +116,7 @@ public function testSuccessful(): void
     public function invalidMovePaths(): array
     {
         return [
-            'null'   => [null],
-            'true'   => [true],
-            'false'  => [false],
-            'int'    => [1],
-            'float'  => [1.1],
             'empty'  => [''],
-            'array'  => [['filename']],
-            'object' => [(object) ['filename']],
         ];
     }
 
diff --git a/tests/UriTest.php b/tests/UriTest.php
index 195933a..3a44278 100644
--- a/tests/UriTest.php
+++ b/tests/UriTest.php
@@ -137,62 +137,6 @@ public function testParseUriPortCannotBeZero(): void
         new Uri('//example.com:-1');
     }
 
-    public function testSchemeMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Scheme must be a string');
-
-        (new Uri())->withScheme([]);
-    }
-
-    public function testUserInfoUserMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('User must be a string');
-
-        (new Uri())->withUserInfo([]);
-    }
-
-    public function testUserInfoPasswordMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Password must be a string or NULL');
-
-        (new Uri())->withUserInfo('', []);
-    }
-
-    public function testHostMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Host must be a string');
-
-        (new Uri())->withHost([]);
-    }
-
-    public function testPathMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Path must be a string');
-
-        (new Uri())->withPath([]);
-    }
-
-    public function testQueryMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Query and fragment must be a string');
-
-        (new Uri())->withQuery([]);
-    }
-
-    public function testFragmentMustHaveCorrectType(): void
-    {
-        $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage('Query and fragment must be a string');
-
-        (new Uri())->withFragment([]);
-    }
-
     public function testCanParseFalseyUriParts(): void
     {
         $uri = new Uri('0://0:0@0/0?0#0');
@@ -353,14 +297,6 @@ public function testStandardPortIsNullIfSchemeChanges(): void
         static::assertNull($uri->getPort());
     }
 
-    public function testPortPassedAsStringIsCastedToInt(): void
-    {
-        $uri = (new Uri('//example.com'))->withPort('8080');
-
-        static::assertSame(8080, $uri->getPort(), 'Port is returned as integer');
-        static::assertSame('example.com:8080', $uri->getAuthority());
-    }
-
     public function testPortCanBeRemoved(): void
     {
         $uri = (new Uri('http://example.com:8080'))->withPort(null);