SCID is an open application to view, edit, and manage collections of chess games.
SCID's low level functions are written in C++ and its graphical interface is in Tcl/Tk. This node addon is a binding to the C++ layer of SCID.
$ npm install scidThe API is currently the same as the Tcl API and is quite low level.
You can look in test/test.js for some basic usage. The API is identical to the Tcl one so the best reference is probably the various Tcl files in the SCID source code.