Eliminating bugs requires sustained, vigilant, holistic, overlapping approaches:

- Code reviews prior to acceptance of commits (Facebook does this)

- Refactoring crap that manages to get through

- Removing features

- Higher-order languages with less code

- Removal of tech debt

- More eyeballs

- Wiser engineers

- Dedicating more time to better engineering

- Coding guidelines that optimize for straightforward code while not being so strict as to hinder strategic exceptions

- Negative LoC as a KPI