Could you try:
- increasing contrast of text (vs background),
- making it horizontal (time is already there, no need to make the whole plot diagonal)
- making different author of language different color or font size than language (and perhaps, bottom to language name).
I believe it would add to readability.
Go, rust, closure, lua, node(js) and a few others have seen some massive interest the past two years, so it isn't that surprising.