I would possibly suggest looking into brook framework, I've never used it but I did use fpweb and it kinda sucks.
If you do use fpweb, I would proxy the application with a REAL web server, Nginx Apache etc. I also used Nginx to redirect 307 redirects to have a proper 404 error page. The developer of fpweb apparently kept the developer of the application in mind, the errors that get generated by the application are annoying to deal with. If a page does not exist it should return a 404, fpweb will instead throw 400 bad request (no shit I developed it, I know its a bad request, thanks for the stack trace lol) a 400 is for methods get, post, delete etc not non existent pages. I don't think fpweb has any kind of routing other than actions which are useless too. YMMV but I would use anything other than fpweb if I was ever going to try again.
I guess I should edit this too. It was very negative, though what i said still stands true.
The piece of software that is using fpweb is very stable with cmem on Linux. It was leaking like crazy without cmem. This piece of software also has an identical golang version, I also wrote. The Pascal version is much much faster than the golang version at least until Pascal hits a celling and go can overtake it with its lightweight multiplexed threads.