Using node.js on Debian/Ubuntu systems

Simply installing the nodejs and npm packages evidently isn’t entirely turn-key.

Trying to run:

sudo npm -g install testacular

results in:

sh: 1: node: not found
npm ERR! error installing chokidar@0.4.0
npm WARN This failure might be due to the use of legacy binary "node" 
npm WARN For further explanations, please read
npm WARN /usr/share/doc/nodejs/README.Debian
npm WARN 
npm ERR! error installing testacular@0.0.17

…because Debian provides the node.js binary as /usr/bin/nodejs and many node packages write their shebangs as #!/usr/bin/node instead. Installing the nodejs-legacy package provides a symlink to resolve these errors. (Or you can just make the symlink yourself!)