Chirpy hooks into macOS Notification Center rather than the Slack or Teams APIs directly, so it works with anything that already posts a system notification — Slack, Teams, Discord, WhatsApp, Mail, Calendar. Rules match by channel, person, or keyword (with AND/OR and wildcards like #prod-*), each with its own sound and volume from a library of 72+ options or your own upload. It’s a 7.8 MB app, now at version 3.0, with a 3-day free trial and a $19.99 one-time license.