an implementation of a OPC UA stack fully written in javascript and nodejs
node-opcua is an experimental OPC-UA stack written in NodeJS.
Why NodeJS ?
Because nodeJs is a great framework to design asynchronous application.
on linux:
$ git clone git://github.com/erossignon/node-opcua.git node-opcua
$ cd node-opcua
$ npm install
$ npm test
on windows:
not tested yet