AddThis is a social bookmarking service that can be integrated into a website with the use of a web widget.
cdnjs is a free distributed JS library delivery service.
Google Analytics is a free web analytics service that tracks and reports website traffic.
OpenResty is a web platform based on nginx which can run Lua scripts using its LuaJIT engine.
ShareThis provides free engagement and growth tools (e.g., share buttons, follow buttons, and reaction buttons) for site owners.