Ember getting killed during install

got a problem: I have a droplet in digitalocean, and I'm trying to install ember-cli there. It keeps getting killed for some reason and I can't quite figure it out. I haven’t found a lot of info on that.

This is how I'm installing -

npm install -g ember-cli

this is the message I get -

npm http GET http://ift.tt/1Qsp0Yf
npm http 304 http://ift.tt/1Qsp0Yf
npm http GET http://ift.tt/1ALYMOL
npm http 200 http://ift.tt/1ALYMOL
Killed

My droplet has 512 RAM and 20GB of space. could it be because of the low RAM? maybe doing something not right? Thanks in advance.