diff --git a/composer.json b/composer.json
index 0869497..afb132a 100644
--- a/composer.json
+++ b/composer.json
@@ -20,7 +20,7 @@
     "require-dev": {
         "phpunit/phpunit": "^7.1",
         "squizlabs/php_codesniffer": "^3.2",
-        "phpstan/phpstan": "^0.9.2"
+        "phpstan/phpstan": "^0.12"
     },
     "autoload" : {
         "psr-4" : {
diff --git a/phpstan.neon b/phpstan.neon
new file mode 100644
index 0000000..9d52fd9
--- /dev/null
+++ b/phpstan.neon
@@ -0,0 +1,2 @@
+parameters:
+    checkMissingIterableValueType: false
diff --git a/src/IO/BufferedOutput.php b/src/IO/BufferedOutput.php
index ad00297..de4e98d 100644
--- a/src/IO/BufferedOutput.php
+++ b/src/IO/BufferedOutput.php
@@ -7,6 +7,9 @@
  */
 class BufferedOutput implements OutputStream
 {
+    /**
+     * @var string
+     */
     private $buffer = '';
 
     public function write(string $buffer): void
diff --git a/src/IO/NonBlockingResourceInputStream.php b/src/IO/NonBlockingResourceInputStream.php
new file mode 100644
index 0000000..5da4a11
--- /dev/null
+++ b/src/IO/NonBlockingResourceInputStream.php
@@ -0,0 +1,38 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpSchool\Terminal\IO;
+
+class NonBlockingResourceInputStream implements InputStream
+{
+    /**
+     * @var InputStream
+     */
+    private $innerStream;
+
+    /**
+     * @param resource $stream
+     */
+    public function __construct($stream = null)
+    {
+        $this->innerStream = new ResourceInputStream($stream ?? STDIN);
+        stream_set_blocking($stream, false);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function read(int $numBytes, callable $callback): void
+    {
+        $this->innerStream->read($numBytes, $callback);
+    }
+
+    /**
+     * @inheritDoc
+     */
+    public function isInteractive(): bool
+    {
+        return $this->innerStream->isInteractive();
+    }
+}
diff --git a/src/IO/ResourceInputStream.php b/src/IO/ResourceInputStream.php
index d72cbd0..b334c37 100644
--- a/src/IO/ResourceInputStream.php
+++ b/src/IO/ResourceInputStream.php
@@ -17,8 +17,13 @@ class ResourceInputStream implements InputStream
      */
     private $stream;
 
-    public function __construct($stream = STDIN)
+    /**
+     * @param resource $stream
+     */
+    public function __construct($stream = null)
     {
+        $stream = $stream ? $stream : STDIN;
+
         if (!is_resource($stream) || get_resource_type($stream) !== 'stream') {
             throw new \InvalidArgumentException('Expected a valid stream');
         }
diff --git a/src/IO/ResourceOutputStream.php b/src/IO/ResourceOutputStream.php
index 005ed22..c4f5fcf 100644
--- a/src/IO/ResourceOutputStream.php
+++ b/src/IO/ResourceOutputStream.php
@@ -17,8 +17,13 @@ class ResourceOutputStream implements OutputStream
      */
     private $stream;
 
-    public function __construct($stream = STDOUT)
+    /**
+     * @param resource $stream
+     */
+    public function __construct($stream = null)
     {
+        $stream = $stream ? $stream : STDOUT;
+
         if (!is_resource($stream) || get_resource_type($stream) !== 'stream') {
             throw new \InvalidArgumentException('Expected a valid stream');
         }
diff --git a/src/InputCharacter.php b/src/InputCharacter.php
index 4aec960..57d6f82 100644
--- a/src/InputCharacter.php
+++ b/src/InputCharacter.php
@@ -28,6 +28,9 @@ class InputCharacter
     public const TAB = 'TAB';
     public const ESC = 'ESC';
 
+    /**
+     * @var array
+     */
     private static $controls = [
         "\033[A" => self::UP,
         "\033[B" => self::DOWN,
@@ -60,7 +63,7 @@ public function isHandledControl() : bool
      */
     public function isControl() : bool
     {
-        return preg_match('/[\x00-\x1F\x7F]/', $this->data);
+        return (bool) preg_match('/[\x00-\x1F\x7F]/', $this->data);
     }
 
     /**
@@ -128,6 +131,6 @@ public static function fromControlName(string $controlName) : self
             throw new \InvalidArgumentException(sprintf('Control "%s" does not exist', $controlName));
         }
 
-        return new static(array_search($controlName, static::$controls, true));
+        return new self(array_search($controlName, static::$controls, true));
     }
 }
diff --git a/src/NonCanonicalReader.php b/src/NonCanonicalReader.php
index 6d26666..7838879 100644
--- a/src/NonCanonicalReader.php
+++ b/src/NonCanonicalReader.php
@@ -3,7 +3,7 @@
 namespace PhpSchool\Terminal;
 
 /**
- * This class takes a terminal and disabled canonical mode. It reads the input
+ * This class takes a terminal and disables canonical mode. It reads the input
  * and returns characters and control sequences as `InputCharacters` as soon
  * as they are read - character by character.
  *
@@ -56,13 +56,15 @@ public function addControlMappings(array $mappings) : void
 
     /**
      * This should be ran with the terminal canonical mode disabled.
-     *
-     * @return InputCharacter
      */
-    public function readCharacter() : InputCharacter
+    public function readCharacter() : ?InputCharacter
     {
         $char = $this->terminal->read(4);
 
+        if ($char === '') {
+            return null;
+        }
+
         if (isset($this->mappings[$char])) {
             return InputCharacter::fromControlName($this->mappings[$char]);
         }
diff --git a/src/UnixTerminal.php b/src/UnixTerminal.php
index 879b1a7..b4dc47d 100644
--- a/src/UnixTerminal.php
+++ b/src/UnixTerminal.php
@@ -1,4 +1,4 @@
-<?php
+<?php declare(ticks=1);
 
 namespace PhpSchool\Terminal;
 
@@ -45,6 +45,11 @@ class UnixTerminal implements Terminal
      */
     private $originalConfiguration;
 
+    /**
+     * @var array
+     */
+    private $signalHandlers = [];
+
     /**
      * @var InputStream
      */
@@ -57,18 +62,33 @@ class UnixTerminal implements Terminal
 
     public function __construct(InputStream $input, OutputStream $output)
     {
-        $this->getOriginalConfiguration();
-        $this->getOriginalCanonicalMode();
+        $this->initTerminal();
+
         $this->input = $input;
         $this->output = $output;
     }
 
+    private function initTerminal() : void
+    {
+        $this->getOriginalConfiguration();
+        $this->getOriginalCanonicalMode();
+
+        pcntl_async_signals(true);
+
+        $this->onSignal(SIGWINCH, [$this, 'refreshDimensions']);
+    }
+
     private function getOriginalCanonicalMode() : void
     {
         exec('stty -a', $output);
         $this->isCanonical = (strpos(implode("\n", $output), ' icanon') !== false);
     }
 
+    private function getOriginalConfiguration() : string
+    {
+        return $this->originalConfiguration ?: $this->originalConfiguration = exec('stty -g');
+    }
+
     public function getWidth() : int
     {
         return $this->width ?: $this->width = (int) exec('tput cols');
@@ -84,9 +104,26 @@ public function getColourSupport() : int
         return $this->colourSupport ?: $this->colourSupport = (int) exec('tput colors');
     }
 
-    private function getOriginalConfiguration() : string
+    private function refreshDimensions() : void
     {
-        return $this->originalConfiguration ?: $this->originalConfiguration = exec('stty -g');
+        $this->width  = (int) exec('tput cols');
+        $this->height = (int) exec('tput lines');
+    }
+
+    public function onSignal(int $signo, callable $handler) : void
+    {
+        if (!isset($this->signalHandlers[$signo])) {
+            $this->signalHandlers[$signo] = [];
+            pcntl_signal($signo, [$this, 'handleSignal']);
+        }
+        $this->signalHandlers[$signo][] = $handler;
+    }
+
+    public function handleSignal(int $signo) : void
+    {
+        foreach ($this->signalHandlers[$signo] as $signalHandler) {
+            $signalHandler();
+        }
     }
 
     /**