How to configure tup build system for different build configurations, e.g. debug or release flags?

Question

I am quite new to tup but still love its features. One issue I am thinking about how does tup support different build options, e.g. debug or release (-> different CFLAGS)?

I did not find any useful results using google.

Answer 1

I found the solution: tup variants, see http://gittup.org/tup/manual.html#lbAE

Thanks!