How to use Compositor: install, layers and key tools

Check the requirements before you install

Compositor runs on macOS 26.0 or later on a Mac with Apple silicon. The author's README says it is macOS only, so Windows and Linux users should look at the unofficial ports listed in the README, which the author does not review or support.

Intel Macs and older macOS versions are not covered by the README's requirements.

• macOS 26.0 or later
• A Mac with Apple silicon
• Xcode 26 or later, only if you want to build from source

Install Compositor on macOS

You can download the latest release from the author's site at robbietilton.com/compositor, or from the GitHub Releases page for the project. The README also gives a Homebrew command for installing the app as a cask.

• Download from robbietilton.com/compositor or GitHub Releases
• Or install with Homebrew using the command shown here

Work with layers, masks and blend modes

Compositor is built around layers and folders. Each layer has opacity and Photoshop's full set of blend modes, and a folder's opacity dims everything inside it. Layer masks can be painted, filled, inverted, blurred and feathered, and they can extend past the layer's own pixels.

Layer effects such as Drop Shadow, Stroke and Outer Glow stay editable at any time. You can merge layers with Merge Down (⌘E for Merge Layers and Merge Group as well) and duplicate, rename, reorder or nest layers by drag and drop.

• Layers and folders with opacity and blend modes
• Layer masks, clipping masks and folder masks
• Adjustment and filter layers
• Merge Down, Merge Layers and Merge Group (⌘E)
• Copy and paste whole layers or folders with ⌘C and ⌘V

Make selections and transform layers

The selection tools include Rectangle and Ellipse Marquee, Freehand and Polygonal Lasso, and the Magic tool, where Wand selects by color and Object traces whatever you click. Tab switches between them. You can also use Select Subject, and Expand, Contract or Feather any selection.

Transforms are non-destructive, so images keep their full resolution. You can move, scale, rotate and flip layers, use free distort with ⌘-drag on a handle, and align or distribute layers from the Move tool's bar or the Layer menu.

• Marquee, Lasso and Magic selection tools
• Select Subject and Expand, Contract or Feather
• Free distort with ⌘-drag, Shift to lock to an axis
• Snapping to canvas and layer edges, plus guides

Paint, retouch and add text

The Brush has adjustable size, hardness, opacity and smoothing, and switches between Paint and Erase with B and E. Shift draws straight lines. If you use a graphics tablet, pen pressure can control the Brush's size and opacity.

Retouching tools include the Spot Healing Brush, Clone Stamp and Blur tool. The Type tool (T) supports multiline text in paragraph boxes, and text can be used as a clipping mask.

• Brush with Paint and Erase modes (B and E)
• Spot Healing Brush and Clone Stamp
• Gradient tool and Shape tool with editable shapes
• Type tool (T) with paragraph boxes

Use adjustments, filters and export your image

Adjustments include Levels, Curves, Hue/Saturation, Exposure and Color Balance, and the Camera Raw filter provides light, color and detail controls in a panel beside the canvas. Filters include Gaussian Blur, Sharpen, Vignette and Lens Effects. Live previews are limited to the selection when there is one.

To save your work as an image, use Export PNG (⇧⌘E), Export JPEG (⇧⌥⌘S) or Export As (⇧⌥⌘W). Export As can also produce a one-page PDF or an animated GIF when a GIF layer is present.

• Export PNG: ⇧⌘E
• Export JPEG: ⇧⌥⌘S
• Export As: ⇧⌥⌘W, for PNG, JPEG, PDF or animated GIF