> I insist on this all the time in code reviews. Variables must have units in their names if there's any ambiguity. For example, `int timeout` becomes `int timeout_msec`.

Same here. I'm still torn when this gets pushed into the type system, but my general rule of thumb in C++ context is:

  void FooBar(std::chrono::milliseconds timeout);

is OK, because that's a function signature and you'll see the type when you're looking at it, but with variables, `timeout` is not OK, as 99% of the time you'll see it used like:

  auto timeout = gl_timeout; // or GetTimeoutFromSomewhere().
  FooBar(timeout);

Common use of `auto` in C++ makes it a PITA to trace down exact type when it matters.

(Yes, I use IDE or a language-server-enabled editor when working with C++, and no, I don't have time to stop every 5 seconds to hover my mouse over random symbols to reveal their types.)