At a Glance:
Compositor is an open-source Photoshop alternative for Apple silicon Macs, combining layered compositing, non-destructive transforms, selections, retouching, filters, PSD/PSB import, and script-writable project files in a familiar image-editing workflow.
Overview:
Compositor is a macOS image editor for compositing and post-processing pixel-perfect images with a Photoshop-oriented workflow. It provides layers, masks, adjustment layers, editable effects, selections, painting and retouching tools, Camera Raw controls, and multiple tabbed projects. The editor imports common image formats plus 8-bit RGB Photoshop PSD and PSB files, retaining supported Photoshop elements as editable content and reporting conversions before applying them. Projects can also be created or edited by scripts and AI agents through the documented .comp folder format.
Key Decision Points:
Platform requirements: Compositor requires macOS 26.0 or later on an Apple silicon Mac; building from source requires Xcode 26 or later.
Photoshop-oriented workflow: Layer blend modes, masks, adjustment layers, keyboard shortcuts, numeric scrubbing, and PSD/PSB import are designed around familiar Photoshop compositing and post-processing patterns.
PSD/PSB compatibility boundaries: Import supports 8-bit RGB files but not CMYK; supported folders, masks, blend modes, basic shapes, and simple horizontal text remain editable, while other vectors and vertical text are rasterized.
Editable, non-destructive operations: Transforms retain source resolution, shapes remain editable, effects can be revised, and adjustment layers preserve the underlying image workflow.
Scriptable project format: A
.compproject is a folder of PNG layers and a manifest, allowing agents and scripts to write projects that update live when open.
Core Features:
Layer compositing: Organize layers and folders with opacity, blend modes, masks, clipping masks, adjustment layers, and GPU-rendered editable effects.
Selections and content-aware editing: Use marquee, lasso, Magic Wand, object tracing, Select Subject, selection refinement, Content-Aware Fill, and content-aware Spot Healing.
Painting, type, and shapes: Paint or erase with adjustable brushes, clone pixels, apply gradients, create editable shapes, and edit multiline text in resizable paragraph boxes.
Adjustments and filters: Apply Camera Raw controls, tonal and color adjustments, blur, noise, vignette, bloom, lens correction, background removal, and selection-limited live previews.
Canvas and file workflows: Work across project tabs with rulers, guides, grids, crop and sizing tools, PSD/PSB conversion reporting, common image imports, JPEG export previews, and background saving.
Non-destructive transforms: Move, scale, rotate, flip, distort, snap, and transform multiple layers or folders while preserving full image resolution.
Use Cases:
Composite layered artwork with masks, blend modes, adjustment layers, editable effects, text, and shapes.
Retouch photographs with Camera Raw adjustments, selection tools, healing, clone, blur, filters, and background removal.
Open supported Photoshop PSD or PSB documents on an Apple silicon Mac and review the conversion report before editing.
Generate or modify Compositor projects through scripts or AI agents using PNG layers and a manifest.
Open-Source Alternative Value:
Compositor provides a free, MIT-licensed Photoshop alternative centered on the compositing and post-processing workflow documented by its author. Users can install a signed build from a release or Homebrew, while developers with Xcode 26 can build the project and modify features. Its documented .comp structure also exposes projects as PNG layers plus a manifest for direct editing by scripts and AI agents.