BOUNCER

Bouncer installs Windows low-level keyboard and mouse hooks and drops any key or button press that arrives faster than a human possibly could after that same key's release — the signature of switch chatter. Everything else passes through untouched; held keys and intentional double-clicks are unaffected by design.

It's built functional-core / imperative-shell: all timing logic lives in a pure, fully unit-tested core where the clock is just a parameter, behind a thin Win32 + egui shell. Safety comes first — fail-open on any doubt, a panic hotkey for instant pass-through, and an eviction watchdog that reinstalls the hook if Windows ever drops it. There is no network code, and nothing keystroke-related ever touches disk.