Adobe Photoshop costs too much and tools like GIMP don’t feel familiar enough for me to stay in flow. That’s why I built Compositor.
The goal was to create a full-featured image editor that is completely free and open source. I used to use Photoshop for compositing and post-processing, so Compositor is built around that workflow - with the tools needed to create a pixel-perfect final image.
Because it’s open source, you can download the Xcode project and add, remove, or modify any feature to fit your workflow.
Get Compositor from robbietilton.com/compositor, or download the latest release directly from GitHub Releases.
brew install --cask robbietilton-compositor- Layers and folders, with opacity and Photoshop's full set of blend modes in its order — a folder's opacity dims everything inside it
- Layer masks: paint, fill, invert, blur and feather them anywhere on the canvas, past the layer's own pixels; link or unlink them to transform a mask on its own
- Clipping masks and folder masks
- Adjustment layers: Hue/Saturation, Levels, Curves, Exposure, Gradient Map, Grain, Black & White, Color Balance, Invert, Gaussian Blur, Motion Blur and Noise
- Layer effects: Stroke, Drop Shadow, Color Overlay, Inner Shadow, Outer Glow and Inner Glow, rendered on the GPU and editable at any time
- Merge Down, Merge Layers and Merge Group (⌘E)
- Duplicate, rename inline, reorder and nest by drag and drop; Option-drag to duplicate; a right-click menu in the Layers panel
- Copy and paste whole layers and folders (⌘C/⌘V with no selection), within a project or between projects, or drag them between projects
- Non-destructive move, scale, rotate and flip — images keep their full resolution however small you make them
- Free distort (⌘-drag a handle), with Shift to lock to an axis
- Transform several layers, or a whole folder, together
- Snapping to canvas and layer edges and centers, with guides
- Exact values for position, size, scale and angle, stepped with the arrow keys
- Flip Layer and Flip Canvas, horizontal and vertical
- Rectangle and Ellipse Marquee, Freehand and Polygonal Lasso, and the Magic tool — Wand selects by color, Object traces whatever you click (Tab switches)
- Select Subject, and Expand, Contract and Feather on any selection
- Add to and subtract from selections, move the outline, or move and duplicate the pixels inside
- Load a layer's pixels or a mask as a selection
- Content-Aware Fill, which can also extend an image past its edges
- Brush with size, hardness, opacity and smoothing, in Paint or Erase mode (B and E), and Shift for straight lines
- Spot Healing Brush (content-aware)
- Clone Stamp, aligned or not, sampling one layer or all of them
- Blur tool, on pixels or masks
- Gradient tool and Shape tool (rectangles, rounded rectangles, ellipses and lines), which stay editable rather than being rasterized
- Type tool (T): inline multiline editing in draggable, resizable paragraph boxes; font, size, color, alignment and spacing in the tool header; transform text and use it as a clipping mask
- Eyedropper and a full color picker
- Camera Raw filter: light, color, curves, color mixer, color grading, detail, optics and geometry, in a panel beside the canvas
- Levels (with Auto), Curves, Hue/Saturation, Exposure, Gradient Map, Grain, Black & White, Color Balance and Invert
- Gaussian Blur and Motion Blur that spread past a layer's edges
- Add Noise, Vignette, Bloom / Glow, Tonal Contrast, Lens Correction and Remove Background
- Live previews, limited to the selection when there is one
- Multiple projects in tabs
- Rulers (⌘R), guides dragged from them, a layout grid with adjustable spacing and subdivisions, and Snap To for guides, grid, layers and document bounds
- Crop with snapping, ratios including 3:4 and 9:16, and Option for symmetric cropping; with a selection, the crop starts at it
- Canvas Size, Image Size and Trim
- Sharp high-quality downsampling when zoomed out, and a pixel grid when zoomed in
- Import JPEG, PNG, HEIC, TIFF, SVG, camera RAW (with a develop step first) and Photoshop PSD and PSB (8-bit RGB; not CMYK). Photoshop folders, masks, blend modes, fill rectangles/ellipses, and simple horizontal text stay editable; other vectors and vertical text become pixels. A conversion report is shown before anything is applied.
- Large documents: the memory budget scales with your Mac, and a Photoshop file too big to open has its layers cropped to the canvas instead
- Export JPEG with a live preview (⇧⌥⌘S); Copy Merged
- Keep working while a project saves
- Photoshop-style keyboard shortcuts throughout, remappable in Edit > Keyboard Shortcuts
- Drag a number's label to scrub its value, as in Photoshop
- Automatic updates, signed and notarized
- AI agents and scripts can build and edit projects directly: a
.compis a folder of PNG layers and a manifest, and an open project updates live as it's written. See Writing Compositor projects
- macOS 26.0 or later on a Mac with Apple silicon
- Xcode 26 or later (to build from source)
Open Compositor.xcodeproj and run the Compositor scheme.
scripts/release.sh builds a Release version, signs it with Developer ID, notarizes and staples it, and packages it into dist/Compositor-<version>.dmg.
It needs, all kept outside this repository:
- a Developer ID Application certificate in the login keychain
- notarization credentials saved with
xcrun notarytool store-credentials "compositor-notary" … create-dmg(brew install create-dmg)
MIT — see LICENSE.