Upstream xcaddy uses the $HOME directory as the temp directory on Darwin
in order to fix an interesting bug.
In order to find version information for Caddy, it runs a command that
needs to operate on file system without "noexec" set, but Darwin's temp
directory has it set.
We can tolerate losing version information, since the alternative is
that xcaddy does not run on Darwin.
A tool that can be used to build the Caddy webserver with plugins.
It functions as its own package manager and calls out to the network, so
it can't build Caddy in nixpkgs, but it's useful for environments that:
1. Do not need sandboxed and reproducible builds.
2. Pin Caddy and plugin versions when using the tool and trust it to be
a reproducible, fixed derivation.