This page will help you troubleshoot common issues that you may run into when using Flight.
If you are seeing a 404 Not Found error (but you swear on your life that it's really there and it's not a typo) this actually could be a problem with you returning a value in your route endpoint instead of just echoing it. The reason for this is intentional but could sneak up on some developers.
Flight::route('/hello', function(){ // This might cause a 404 Not Found error return 'Hello World'; }); // What you probably want Flight::route('/hello', function(){ echo 'Hello World'; });
The reason for this is because of a special mechanism built into the router that handles the return output as a single to "go to the next route". You can see the behavior documented in the Routing section.