Tool to show code age across VCS history

Question

I'm sure there was a Show HN last year for a tool that generates a stacked line graph of the amount of code that has been churned over time. The X axis is time, and the Y is lines of code, and each layer in the stacked graph neatly shows how much original code remains in the code base, and how much has been rewritten. I think its repo shows example graphs for big projects including the Linux kernel.I've searched for every relevant keyword I can think of but cannot find this tool again. Does anyone also remember it and have a link to it?

sdesol · Accepted Answer

My solution (https://gitsense.com) captures every line change but it's currently not designed to tell you how munch of the original code base is still being used. If the solution could do this, I would have guess the numbers wouldn't be very accurate or comes with a big caveat since this would be extremely difficult to do.I guess you can track every blame, but that would be extremely computationally heavy and doable, if you are looking for something that can give you a timeline for something as big as the linux kernel.