Valgrind won’t show you leaks where you (or a GC) still holds a reference. This could mean you’re holding on to large chunks of memory that are still referenced in a closure or something. I don’t know what language or anything about your project, but if you’re using a GC language, make sure you disable GC when running with valgrind (a common mistake). You’ll see a ton of false positives that the GC would normally clean up for you, but some of those won’t be false positives.

It will, but they will be abbreviated (only total amount shown, not the individual stack traces) unless you ask to show them in full.

Ghostty is written in Zig.