Phalcon without app bootstrab

I have a legacy system, which I want to build some service using Phalcon, then I can use my new built services via php composer.

My question, how I can call phalcon services without initiate phalcon app, as I do not have a bootstrap


what is file loader, sometime it is index.php you can add some service phalcon in that

The bootstrap file basically just configures the services you want to use - having a bootstrap file doesn't necessarily mean you need to have a full Phalcon app.