Compositor

Compositor is a free, open-source Photoshop-style image editor for macOS, written in Swift. It is built around the compositing and post-processing workflow: layers with blend modes and opacity, layer and folder masks, clipping masks, and adjustment layers for Hue/Saturation, Levels, Curves, Exposure, Gradient Map and Grain.

The toolset will feel familiar to Photoshop users: Marquee and Lasso selection tools plus a Magic Wand, Brush with size, hardness and opacity, Spot Healing Brush, Clone Stamp, Blur, Gradient and Shape tools, a Type tool with paragraph boxes, and a Content-Aware Fill that can also extend images past their edges. Adjustments include Levels with Auto, Curves, Gaussian and Motion Blur, Add Noise, Lens Correction and Remove Background, all previewed live and limited to the active selection.

Transforms are non-destructive — images keep their full resolution no matter how you scale them — and a Photoshop-style keyboard shortcut scheme is used throughout. Projects open in tabs, and JPEG, PNG, HEIC and TIFF can be imported (including dropped screenshots) with JPEG export and Copy Merged support.

Compositor is MIT licensed and developed openly on GitHub, so feature changes and fixes happen in public. It only runs on macOS, while Photoshop is cross-platform — so it is a strong alternative for Mac users who want a native, lightweight editor without a subscription, but Mac-only availability is the main trade-off.