How can developers ensure optimal performance when working with date and time functions in PHP?

To ensure optimal performance when working with date and time functions in PHP, developers should use built-in functions like strtotime() and date() instead of custom date manipulation code. Additionally, caching the results of expensive date/time calculations can help reduce the overall load on the server.

// Example of using strtotime() and date() functions for optimal performance
$timestamp = strtotime('2022-01-01');
$formatted_date = date('Y-m-d', $timestamp);
echo $formatted_date;