I am having issues building an app because node-sass keeps failing with the error.
ERROR in Missing binding /Users/warren/Sites/random-docs/my-cms/nod
I had a similar problem and the reason was that there were two versions of Node installed in my machine: one "global" and another one at the project level. Sass will build correctly only if the Gulp build is running under Node.js 4.x version, so make sure you upgrade the version of Node you are using.
PS: If you completely remove the node_modules folder in your project and re-build from scratch, npm will download the correct dependencies for your current system & node version.