OpenSSL is compiled and installed as a shared library, and so it is available to third party packages, like many LuaRocks packages that otherwise will fail to install properly
Added git to the installed packages, as it is needed for some LuaRocks packages. If you don't need it feel free to remove it.
OpenResty is installed in /opt/, but it is configurable via ENV variables. The ENV variables are used instead of ARG ones so you can use them in your config files or scripts (ported from ficusio/openresty).
The number of cores is detected automatically, so you'll always utilise the power of your host without changing any parameter (ported from ficusio/openresty).
It is a minimal OpenResty 1.9.15.1 build, with the following modules included: