In which of the following situations can I use a GPL component in my website without having to GPL or disclose the source code of my entire site?
The component is an executable program called by the backend via something like
The component is a dynamic link library invoked at runtime by the backend.
The component is a static library linked at build time with the backend.
Note that I only intend to use the GPL component to support the features in my site, not to modify or distribute the GPL component for others to use.