LightCraft

Your photos. Your pixels. Your machine.

A fast, beautiful, open-source photo library and non-destructive raw developer — written from scratch in pure Rust.
Native on macOS, Windows and Linux. In the browser via WebAssembly. Drivable end-to-end by AI agents over MCP.

Features · Before & after · Agents & MCP · Quick start · Roadmap

_{Ansel Adams, “The Tetons and the Snake River” (1942) — public domain, U.S. National Archives — developed in LightCraft.}

Edit like you mean it

LightCraft is a complete darkroom in a single native app. Every adjustment is non-destructive — your originals are never touched — and every slider renders through a scene-referred, wide-gamut, 32-bit float pipeline so highlights roll off like film, shadows open up without halos, and colour stays clean from capture to export.

☀️ Light Exposure, Contrast, Highlights, Shadows, Whites, Blacks — with edge-aware local tone mapping (a guided filter on log-luminance), so pulling −100 Highlights recovers a blown sky without the grey halos you'd get from a naive curve. 🎨 Color White balance by temperature & tint (Kelvin for raw, relative for JPEG) with presets, Auto and a click-to-neutralise eyedropper. Vibrance that protects skin tones, Saturation, an 8-band Color Mixer (hue / saturation / luminance) and 3-way Color Grading wheels with blending and balance — all computed in OkLCh, a modern perceptual colour space.

✨ Effects Texture for fine detail, Clarity for mid-tone punch, Dehaze (dark-channel-prior with guided refinement — push it negative to add atmosphere), post-crop Vignette with highlight priority, roundness and feather, and resolution-independent film Grain with size and roughness. 📈 Tone Curve Parametric region curve with movable splits plus point curves for RGB, Red, Green and Blue. Curves are monotone by construction — no accidental tone inversions, ever.

Color grading, the cinematic way

Split-tone shadows, midtones and highlights independently with drag-anywhere colour wheels. Below, Dorothea Lange's Migrant Mother gets a warm print-like tone — highlights at 42°, shadows at 28° — in two drags.

_{Dorothea Lange, “Migrant Mother” (1936) — public domain, Library of Congress.}

Before & after

Hold \ to peek at the original, press Y for side-by-side, or Shift+Y for a split view. Every image below is a real screenshot of LightCraft, captured automatically by an agent through the control channel.

The Tetons and the Snake River — Highlights −45, Shadows +38, Clarity +28, Dehaze +18. Ansel Adams, 1942 (public domain).	Migrant Mother — Shadows +42, Texture +18, split-toned grade, vignette. Dorothea Lange, 1936 (public domain).
Earthrise — Dehaze +22, Highlights −30, warmer white balance, Vibrance +22. NASA / Bill Anders, Apollo 8, 1968 (public domain).	The Blue Marble — Highlights −38, Blacks −20, Dehaze +15, Vibrance +30. NASA, Apollo 17, 1972 (public domain).

Masking that goes where you point

Paint with a Brush (size, feather, flow, density, erase), drop Linear and Radial Gradients with draggable pins, or select by Luminance Range, Color Range, Sky, Subject and Background. Combine components with Add / Subtract / Intersect, invert any of them, and dial in 15 local adjustments per mask — Temp, Tint, Exposure, Contrast, Highlights, Shadows, Whites, Blacks, Texture, Clarity, Dehaze, Hue, Saturation, Sharpness, Noise — plus an overall Amount.

Presets, profiles & the Color Mixer

Eighteen hand-built presets ship in the box — Golden Hour, Teal & Orange, Faded Matte, Selenium Tone, Crisp Landscape and more — each with an Amount slider from 0 to 200 %. Save your own from any group of settings, mark favourites, copy/paste or sync edits across a whole selection with exactly the groups you choose.

✂️ Crop, straighten & geometry Free or locked aspect ratios (1:1, 4:5, 5:7, 2:3, 4:3, 16:9, 16:10, original), drag-to-rotate straightening that always keeps the largest crop inside the image, thirds / grid / golden-ratio overlays, flips and 90° rotations, plus manual Vertical, Horizontal, Rotate, Aspect, Scale and Offset transforms.	⚫️ Black & White One click (V) to monochrome with an 8-band B&W Mix that lets you darken skies or glow foliage — then tone it with Color Grading for selenium, sepia or split-tone prints.

Organize everything

A library that stays out of your way: All Photos, Recently Added, Picks, By Date, Albums nested in Folders, and Recently Deleted. Rate with 0–5, flag with P / X / U, colour-label with 6–9. Search understands fields — rating:>3 flag:pick iso:>800 camera:x2 date:2026-04 keyword:mountains — and every view sorts by capture date, import date, edit date, name, rating or size. Justified Photo Grid and Square Grid views are virtualized, so they stay smooth whether you have forty photos or forty thousand.

Built for agents

Every menu item, slider, brush stroke, crop handle and keystroke in LightCraft is a command with a stable id and JSON parameters — the UI, the keyboard, the CLI, a JSON-lines control channel and an MCP server all dispatch through the same entry point. An agent can cull a shoot, develop it, mask a sky and export it — and see the result.

lightcraft --control 7980 ~/Pictures/trip

{"method": "engine.execute", "params": {"command": "photo.flag",  "params": {"flag": "pick"}}}
{"method": "engine.execute", "params": {"command": "develop.set", "params": {"values": {"light.highlights": -45, "light.shadows": 38}}}}
{"method": "engine.execute", "params": {"command": "mask.add",    "params": {"kind": "radial", "center": [0.62, 0.4], "rx": 0.2, "ry": 0.14}}}
{"method": "ui.clickWidget",   "params": {"id": "slider:effects.clarity"}}       // drive any widget by name
{"method": "ui.pointer",       "params": {"events": [{"kind":"down","x":0.2,"y":0.3}, {"kind":"up","x":0.4,"y":0.3}]}}
{"method": "ui.screenshot",    "params": {"path": "after.png"}}

• 91 engine commands and 48 UI commands — list them all with engine.commands, read every slider's range, default and current value with develop.controls.

• MCP server — lightcraft-cli mcp gives Claude (or any MCP client) ~100 tools: import, query, develop, mask, render (returned as an image), export — headless, or attached to the running app with screenshots, clicks and gestures. See docs/mcp.md.

  cargo build --release -p lightcraft-cli
  claude mcp add lightcraft -- "$PWD/target/release/lightcraft-cli" mcp ~/Pictures/shoot          # headless
  claude mcp add lightcraft-app -- "$PWD/target/release/lightcraft-cli" mcp --connect 127.0.0.1:7980  # live app
  

• Scriptable CLI — lightcraft-cli render in.dng -o out.jpg --set light.exposure=0.7 --preset ….

• Undo for everything, including agent actions: a slider drag (or a scripted burst of updates) is one undo step.

• Every widget is addressable (ui.widgets) and clickable by name, so agents can operate the real UI, not a side door.

• The screenshots in this README were produced by docs/showcase/ scripts, end to end. Protocol reference: docs/control-protocol.md.

Fast, native, private

• Pure Rust, no C. Our own RAW decoders (DNG, Canon CR2, Sony ARW, Nikon NEF, Fujifilm RAF incl. X-Trans, Panasonic RW2, Pentax PEF, Olympus ORF), our own colour science, our own pipeline. JPEG, PNG, TIFF, WebP, PSD composites and JPEG XL open today.
• Scene-referred & wide-gamut. Linear Rec.2020 float internally, Bradford-adapted white balance, gamut mapping instead of clipping, a filmic shoulder for raw and pixel-exact pass-through for JPEGs you haven't touched.
• Resolution-independent edits. Radii and brush sizes are relative to the image, so a 400 px preview, your 5K display and a 60 MP export look the same.
• Background rendering. A worker pool renders the loupe, before/after and every visible thumbnail off the UI thread; drafts during drags, full quality on release.
• Local-first. No account, no cloud, no telemetry, no subscription. Your catalog is an append-only log of human-readable operations you can diff, back up or replay.

Feature status

LightCraft is young and moving fast — see the roadmap for estimates.

Area	Status
Library: albums, folders, ratings, flags, labels, search, sort, grids, filmstrip	✅
Light, Color, Effects, Tone Curve, Color Mixer, Color Grading, B&W	✅
Masking: brush, linear, radial, luminance/colour range, add/subtract/intersect	✅ (AI subject/sky use classical heuristics for now)
Crop, straighten, flip, rotate, aspect ratios, overlays	✅
Profiles (Color, Neutral, Vivid, Landscape, Portrait, Monochrome — our own looks), presets, versions, history, copy/paste/sync settings	✅
Control channel + every widget addressable	✅
RAW: DNG, CR2, ARW, NEF (uncompressed), Fujifilm RAF (Bayer + X-Trans), Panasonic RW2, Pentax PEF, Olympus ORF; embedded previews for every format incl. CR3	✅ · compressed NEF/RAF/ORF, CR3 decode 🚧
Detail: sharpening, luminance + colour noise reduction	✅ · AI Denoise, Super Resolution ⬜
Remove / Heal / Clone spots (auto source)	✅ · content-aware fill (PatchMatch), Red Eye 🚧
Export: JPEG / PNG / TIFF / WebP / AVIF, sizing, file-size limit, output sharpening, naming, batch, metadata policy, text watermark	✅ · DNG export, image watermark ⬜
Library persistence (crash-safe op log + snapshots), disk thumbnail cache, import with duplicate detection	✅
MCP server (headless or live app, persistent libraries), CLI, control channel	✅
XMP sidecars (read/write, auto-write), reading crs: develop settings, preset files (.lcpreset, XMP presets)	✅
Optics (distortion, vignetting, auto + manual CA, defringe, DNG-embedded lens corrections), Geometry (transforms, Constrain Crop), Upright (Auto/Level/Vertical/Full/Guided)	✅ · camera lens profiles (our own) ⬜
GPU pipeline	🚧
Web build (same UI in the browser via WASM; in-memory imports, export downloads)	✅ · persistence, workers 🚧

Quick start

git clone https://github.com/storytold/lightcraft && cd lightcraft
cargo run --release -p lightcraft                       # opens your library (~/Pictures/LightCraft Library; a new one starts with demo photos)
cargo run --release -p lightcraft -- ~/Pictures/trip    # import your photos (folders are scanned, duplicates skipped)
cargo run --release -p lightcraft -- --memory           # a throwaway in-memory demo session (writes nothing)
cargo run --release -p lightcraft -- --control 7980     # with the automation channel
cargo xtask web --serve                                 # the same app in the browser: http://127.0.0.1:8080/
cargo run --release -p lightcraft-cli -- render photo.jpg -o out.jpg --set light.exposure=0.5
cargo xtask ci                                          # fmt, clippy, tests, layering, wasm checks

The web build needs the wasm32-unknown-unknown target and the matching wasm-bindgen CLI (cargo xtask web prints the exact install command); see docs/web.md.

Keyboard: G grid · D detail · E edit · C crop · M masking · Shift+P presets · \ original · Y before/after · Z zoom · J clipping · ⌘Z undo · ⌘/ all shortcuts.

How it's built

An engine-first Cargo workspace of small, tested crates with enforced layering (cargo xtask layers): geom, color, raster, tiff → raw, codecs, meta, develop → pipeline → catalog → engine → ui-egui. The egui frontend is one swappable crate; nothing below it knows a UI exists. mcp and the apps (lightcraft, lightcraft-cli) sit on top of engine.

Contributing

Humans and agents follow the same rules — read AGENTS.md first. The short version:

• Clean-room. Never read Adobe binaries or GPL raw/photo code (darktable, RawTherapee, LibRaw, rawspeed, dcraw…); work from public specs and black-box observation.
• No Adobe assets, ever — no icons, screenshots, presets, profiles, LUTs or fonts from Adobe products. Every image, icon and font in the repo is original, public domain, Creative Commons, OFL or permissively licensed, and has an entry in assets/ATTRIBUTION.md added in the same commit.
• Pure Rust, enforced crate layering, everything is a command, and cargo xtask ci green before every commit (one task id per commit).

Crafting Apps

Clean-room, pure-Rust creative tools from the same workshop — native on macOS, Windows and Linux, and in the browser.

PhotoCraft Layered raster image editor — a Photoshop-class app with layers, masks, adjustments, brushes and PSD support.

DrawCraft Vector illustration — an Illustrator-class app with pen tools, live shapes, Pathfinder, type and SVG/PDF.

FilmCraft Non-linear video editor — a Premiere-class app with its own H.264/ProRes/AAC codecs, timeline and colour.

LightCraft Photo library and raw developer — a Lightroom-class app with a scene-referred pipeline, masking and presets.

PrintCraft PDF viewer and editor — an Acrobat-class app for reading, organizing, annotating and editing PDFs.

Credits

Showcase photographs are public-domain works, used via Wikimedia Commons: Ansel Adams, The Tetons and the Snake River (1942, U.S. National Archives); Dorothea Lange, Migrant Mother (1936, Library of Congress); Bill Anders / NASA, Earthrise (1968); NASA, The Blue Marble (1972). The demo library is procedurally generated by LightCraft. UI font: Inter (SIL OFL). All icons are original. See assets/ATTRIBUTION.md.

LightCraft is an independent project and is not affiliated with or endorsed by Adobe. Licence: MIT OR Apache-2.0. By the artcraft team.