diff --git a/README.md b/README.md
index 34da021..82d10db 100644
--- a/README.md
+++ b/README.md
@@ -11,6 +11,11 @@ Install the package via composer:
 composer require sandeshjangam/tiny-ssh-php
 ```
 
+## Requirements
+
+- Php >= 7.4
+- phpseclib ^3.0
+
 ## Usage
 
 Simple SSH command using password authentication:
diff --git a/composer.json b/composer.json
index db88597..2099aba 100644
--- a/composer.json
+++ b/composer.json
@@ -13,15 +13,19 @@
         {
             "name": "Sandesh Jangam",
             "email": "sandesh2643@gmail.com"
+        },
+        {
+            "name": "Jordan Hall",
+            "email": "jordan@hall05.co.uk"
         }
     ],
     "require": {
-        "php": ">=7.1",
+        "php": ">=7.4",
         "phpseclib/phpseclib": "^3.0"
     },
     "require-dev": {
-        "nunomaduro/phpinsights": "^2.11",
-        "pestphp/pest": "^2.35"
+        "nunomaduro/phpinsights": "*",
+        "pestphp/pest": "*"
     },
     "config": {
         "allow-plugins": {
diff --git a/src/Sftp.php b/src/Sftp.php
index 5cb1741..e3cd387 100644
--- a/src/Sftp.php
+++ b/src/Sftp.php
@@ -14,7 +14,7 @@ final class Sftp extends SshBase
     /**
      * The SSH2 connection object.
      */
-    private SFTP2 $sftp;
+    private ?SFTP2 $sftp;
 
     /**
      * Connects to the remote server using the configured details.
@@ -35,6 +35,10 @@ public function connect(): self
             $this->sftp->setTimeout($this->timeout);
         }
 
+        if ($this->keepAlive) {
+            $this->sftp->setKeepAlive($this->keepAlive);
+        }
+
         $this->connected = true;
 
         return $this;
@@ -99,6 +103,20 @@ public function getFingerprint(): string
         return $this->sftp->getServerPublicHostKey();
     }
 
+    /**
+     * Set Keep Alive. Default to no keep alive.
+     *
+     * @param int $interval
+     */
+    public function keepAlive($interval): self
+    {
+        $this->keepAlive = $interval;
+        if ($this->sftp) {
+            $this->sftp->setKeepAlive($this->keepAlive);
+        }
+        return $this ;
+    }
+
     /**
      * Authenticates with the SFTP server using either a private key or a password.
      *
diff --git a/src/Ssh.php b/src/Ssh.php
index 7c2629d..054b1db 100644
--- a/src/Ssh.php
+++ b/src/Ssh.php
@@ -13,7 +13,7 @@ final class Ssh extends SshBase
     /**
      * The SSH2 connection object.
      */
-    private SSH2 $ssh;
+    private ?SSH2 $ssh = null;
 
     /**
      * Connects to the remote server using the configured details.
@@ -34,6 +34,10 @@ public function connect(): self
             $this->ssh->setTimeout($this->timeout);
         }
 
+        if ($this->keepAlive) {
+            $this->ssh->setKeepAlive($this->keepAlive);
+        }
+
         $this->connected = true;
 
         return $this;
@@ -57,14 +61,10 @@ public function disconnect(): void
     /**
      * Execute a command
      *
+     * @param string|array $command $command
      * @throws RuntimeException
      */
-    /**
-     * Execute a command
-     *
-     * @throws RuntimeException
-     */
-    public function execute(string|array $command): SshCommand
+    public function execute($command): SshCommand
     {
         if (! $this->connected) {
             throw new RuntimeException('Could not execute command. ' . self::ERROR_NOT_CONNECTED);
@@ -89,6 +89,20 @@ public function getFingerprint(): string
         return $this->ssh->getServerPublicHostKey();
     }
 
+    /**
+     * Set Keep Alive. Default to no keep alive.
+     *
+     * @param int $interval
+     */
+    public function keepAlive($interval): self
+    {
+        $this->keepAlive = $interval;
+        if ($this->ssh) {
+            $this->ssh->setKeepAlive($this->keepAlive);
+        }
+        return $this ;
+    }
+
     /**
      * Authenticates with the SSH server using either a private key or a password.
      *
diff --git a/src/SshBase.php b/src/SshBase.php
index e1bb893..1ddfb3a 100644
--- a/src/SshBase.php
+++ b/src/SshBase.php
@@ -46,6 +46,11 @@ abstract class SshBase
      */
     protected int $timeout = 10;
 
+    /**
+     * The Keep Alive Interval in seconds for the SSH connection. Defaults to 10.
+     */
+    protected int $keepAlive = 10;
+
     /**
      * Whether the SSH connection has been established.
      */
@@ -140,6 +145,7 @@ public function timeout(int $timeout): self
         return $this;
     }
 
+
     /**
      * Returns true if the connection is established, false otherwise.
      */
@@ -158,6 +164,8 @@ abstract public function connect(): self;
      */
     abstract public function disconnect(): void;
 
+    abstract public function keepAlive($interval): self;
+
     /**
      * Validates the connection arguments.
      * If any of the required arguments are empty, an exception will be thrown.
diff --git a/src/SshCommand.php b/src/SshCommand.php
index bc0f6ff..b61fa32 100644
--- a/src/SshCommand.php
+++ b/src/SshCommand.php
@@ -20,8 +20,9 @@ final class SshCommand
 
     /**
      * The output of the command.
+     * @var string|false 
      */
-    private string|false $output;
+    private $output;
 
     /**
      * The error output of the command.
@@ -30,8 +31,9 @@ final class SshCommand
 
     /**
      * The exit status of the command.
+     * @var string|false 
      */
-    private int|false $exitStatus;
+    private $exitStatus;
 
     /**
      * Constructs a new instance of the SshCommand class.
@@ -69,7 +71,7 @@ public function execute(): self
      *
      * @return bool|string The raw output, or false if no output was captured.
      */
-    public function getRawOutput(): string|false
+    public function getRawOutput()
     {
         return $this->output;
     }
@@ -102,16 +104,18 @@ public function getError(): string
 
     /**
      * Returns the exit status of the command.
+     * @return int|false
      */
-    public function getExitStatus(): int|false
+    public function getExitStatus()
     {
         return $this->exitStatus;
     }
 
     /**
      * Check if the exit status of the command matches the given status.
+     * @param int|false $status
      */
-    public function isExitStatus(int|false $status): bool
+    public function isExitStatus($status): bool
     {
         return $this->exitStatus === $status;
     }