Ask HN: How do you track your daily productivity?

I am creating an app and I need to be able to allow users to measure their productivity at any given activity. Since I code I am starting with that activity and I would like to understand all the ways people track their productivity ie: velocity, github commit activity, lines of code etc....

Thank you in advance for any help you are able to provide.

Note: My no noprocrast setting only allows me 10 min of HN a day so I will not be able to respond until tomorrow.