Code snippets - server returns 500

[IbrahimTanyalcin]

This is the repo I am talking about: https://github.com/IbrahimTanyalcin/lexicon-rainbow

I have a single example in the default 'snippets' folder. (http://biojs.io/d/lexicon-rainbow)
Sometimes the sample works, but sometimes the server returns 500. Strangely if you change the link
"http://workmen.biojs.net/demo/lexicon-rainbow/proteins" to
"http://workmen.biojs.net/demo/lexicon-rainbow/proteins.js" you can already see the file there.

Any leads?
Note: both dependencies are served over http.

Thanks!