Replacing my old CGI Support

Site URL: https://springtail-chipmunk-pk3k.squarespace.com/

I am moving my website from a privately hosted server onto SquareSpace.

My old server also allowed my to add a server side CGI that I used for a simple logging task.

POST requests to a specific page resulted in an entry being added to a server side held log file.

In the absence of having my own private server, and given that SquareSpace does not allow server side CGI support, can anyone suggest an alternative approach to handle this kind of logging.

My usage case is my own application generating a POST request that gets picked up by a webserver and handled by a CGI script. The logging URL does not have to be directly associated with my SquareSpace website if you can suggest someother entirely different mechanism.

Many thanks for any suggestions -- Michael Ellis