Do I need to build bounce handling myself?

Usually, yes—if you’re reading a physical button or switch directly, you should plan for debouncing yourself unless your hardware or library explicitly does it for you.

Why

Mechanical contacts don’t transition cleanly. When pressed or released, they can rapidly toggle on/off for a few milliseconds, which can look like multiple presses.

When you might not need to

• Your microcontroller board or input module has built-in debounce
• You’re using a library that already debounces the input
• The signal comes from a clean digital source rather than a mechanical contact

Common ways to handle it

• Software debounce: ignore changes until the signal has been stable for a set time
• Hardware debounce: RC filter, Schmitt trigger, or dedicated debounce circuitry
• Combination: hardware for cleanup, software for robustness

Rule of thumb

If it’s a button, reed switch, relay contact, or mechanical encoder, assume bounce exists and handle it.

If you want, I can show you a simple debounce approach for your specific platform (Arduino, Raspberry Pi, STM32, etc.).