What best practices should PHP developers follow to avoid deprecated functions and ensure future compatibility?

To avoid deprecated functions and ensure future compatibility in PHP development, developers should regularly update their codebase to use the latest recommended functions and features. They should also pay attention to PHP release notes and documentation to stay informed about deprecated functions and their replacements. Additionally, developers can use tools like PHP_CodeSniffer to automatically detect and fix deprecated functions in their code.

// Example of using a deprecated function and its replacement
// Deprecated function: mysql_connect()
// Replacement function: mysqli_connect()

// Deprecated function
$connection = mysql_connect('localhost', 'username', 'password');

// Replacement function
$connection = mysqli_connect('localhost', 'username', 'password');