I’ve learned not to go against the grain with tools, at least at big companies. Probably some dev productivity team has already done all the annoying work needed to make the company’s codebase work with some debugger and IDE, so I use that: currently, it’s VS Code and LLDB, which is fine. IntelliJ and jdb at my last job was probably better overall.

My workflow is usually:

1. insert a breakpoint on some code that I’m trying to understand

2. attach the debugger and run any tests that I expect to exercise that code

3. walk up and down the call stack, stepping occasionally, reading the code and inspecting the local variables at each level to understand how the hell this thing works and why it’s gone horribly wrong this time.

4. use my new understanding to set new, more relevant breakpoints; repeat 2-4.

Sometimes I fiddle with local variables to force different states and see what happens, but I consider this advanced usage, and anyway it often doesn’t work too well on my current codebase.