Snapmark
A native macOS menu-bar app for capturing, annotating, and sharing screenshots.
Role · Solo — learning project
Language
Swift
Type
Menu-bar agent
Take a screenshot with a hotkey, point at what matters with arrows, boxes, and text, and paste. Built in Swift with ScreenCaptureKit, SwiftUI, and AppKit, and tuned for the specific workflow of pasting annotated screenshots into AI coding agents.
An honest framing
Snapmark is a personal learning project, not a commercial product. Its explicit goal is to reproduce the parts of CleanShot X that a keyboard-driven developer actually uses, in order to learn how a real native Mac app is built — a menu-bar agent, global hotkeys, screen capture, an interactive drawing canvas, screen recording, and clipboard integration.
"CleanShot X already does this" is the correct observation and not an objection. The output of the project is the knowledge of how those pieces fit together on macOS, which is not obtainable by reading about them.
What it covers
The interesting surface is all the parts a cross-platform toolkit would have hidden: running as a background agent with no dock icon, registering global hotkeys that work when unfocused, driving ScreenCaptureKit, and building a real interactive drawing canvas in AppKit rather than a toy one.