Why “read the docs first” fails past a certain scale. Three concrete steps to turn a million-line codebase into something you can actually walk through. It’s the build-first precondition no one talks about.
Grep, the debugger, git history, and a personal notebook — the toolkit every senior C++ dev will recommend to you, regardless of stack. Why Go-to-Definition degrades on large codebases (with Microsoft’s own engineering explanation), and where C++-aware extensions shine.
Four candidates for your first useful PR, ordered from least risky to slightly more effort. Chesterton’s Fence applied to legacy code. Why characterization tests are the highest-leverage move most new hires skip.
What you should expect to be delivered after 90 days (and what it doesn’t). The senior secret backed by a quote from experienced devs you’ll want to sit with.