Very good but still...
I loved the "old school text adventure meets unix-like terminal" look and feel, but there are a few things that prevented me from giving a higher vote.
For example, why did hitting backspace cancel the whole line instead of just one character? It was a bit annoying.
Also, why use cat to list files and not ls?
And, more importantly, it ended just too soon! I expected more explanations about who you are, why you are accessing the servers of some hidden bunker, what the virus is about, etc, etc...
Still, the game shows a lot of promise, it would be great to see a longer version or a sequel, with some more puzzles and more story.
I wrote a quick walkthrough for anyone who is stuck: