Can't publish VS Code extension anymore after `npm update`?

I just can't publish my extension anymore.
It just worked fine before I ran npm update.

Now it all says:

npm ERR! Darwin 15.6.0
npm ERR! argv "/usr/local/bin/node" "/usr/local/bin/npm" "run" "vscode:prepublish"
npm ERR! node v6.10.2
npm ERR! npm  v3.10.10
npm ERR! code ELIFECYCLE
npm ERR! eppz-code@1.1.25 vscode:prepublish: `tsc -p ./`
npm ERR! Exit status 2
npm ERR! 
npm ERR! Failed at the eppz-code@1.1.25 vscode:prepublish script 'tsc -p ./'.
npm ERR! Make sure you have the latest version of node.js and npm installed.

See dependencies in package.json to get the full picture.

I tried with countless node versions (6.x to 7.x), no luck with any.
Anyone with similar issues ended up in a solution?

via Geri