Original link: How we safely removed 10,000 lines of code using Emerge Tools’ Reaper / DuoLingo blog.
The specific app is not important. The specific tool is not important. I am not even impressed by removing 1% of code - that seems like very low share of dead code.
But looking for dead code and remove it is important. In a major code base like 10 MLOC then it is highly likely that there are lots of code that cwill never be used. It is not being removed because the problem has not been identified.
One may ask why it matters. The use disk and memory space may very well be irrelvant. It matters for software maintenance - when someone need to search for some code then hits in dead code is waste of time - when someone need to convert code to new versions of something then converting dead code is waste of time.