Suggestion: use ctags to list all functions, variable names in your code. Look for ambiguity (e.g. variable name "i"). Look at neighbouring code. Zoom in and out. A small bug in the most-used code is actually more serious than a big bug in code that rarely gets used.
"How long can you work on making a routine task before you're spending more time than you save?"
"level of detail codified in functional, performance and interface requirements"
functions, usage frequency, APIs.
"usually because your interface requirements are not specified well enough"
It's probably a bug in the API.
https://martinfowler.com/bliki/TwoHardThings.html
"There are only two hard things in Computer Science: cache invalidation, naming things, and off-by-one errors"
https://en.wikipedia.org/wiki/Ctags
Suggestion: use ctags to list all functions, variable names in your code. Look for ambiguity (e.g. variable name "i"). Look at neighbouring code. Zoom in and out. A small bug in the most-used code is actually more serious than a big bug in code that rarely gets used.
"How long can you work on making a routine task before you're spending more time than you save?"
https://xkcd.com/1205/