I had high hopes for Kylix back around the turn of the millennium. At that time my company was looking moving an organization with field agents to a full Linux-based system. Our options were: 1. Keep the existing CA Clipper accounts receivable/accounts payable apps and run on emulated DOS. 2. Attempt to leverage the Harbour language (CA Clipper compatible web based thing). 3. Rewrite the system in Delphi/Kylix. We actually got fairly far with Kylix and I'll always be a fan of Delphi. In the end a pure web-based rewrite won over all those original options. I feel bad for whomever took over that old PHP4 stuff!

Granted, I never used Kylix, but it seems that it had all sorts of problems when it was first released. I don't remember, was Kylix available for Mac?

IIRC it wasn't VCL but another framework like VCL that was built on Qt.

LCL (Lazarus' equivalent of VCL) took another approach where the base stuff are very Windows-y (due to the VCL heritage) but the backends have to essentially implement not only the backend-specific (Gtk, Qt, etc) widget functionality but also a small subset of the Windows API.

While this makes porting harder for the Lazarus developers, it makes it easier to port stuff between OSes and even port stuff from Delphi to Lazarus (some developers can also use both Delphi and Lazarus - e.g. AFAIK Total Commander uses Delphi for the 32bit builds and Lazarus for the 64bit builds).