It's a menu bar app that lets you define a "focus workspace" - a set of apps that should be visible. Press ⌘⇧P and everything else hides instantly.
Features: - Multi-monitor: assign apps to specific screens - Per-app maximize toggle - Native Swift, ~2MB - MIT licensed
Website: https://gabrycina.github.io/FocusMode/ GitHub: https://github.com/gabrycina/FocusMode
Happy to answer questions about the implementation.