A native Rust infinite canvas for planning, working and sketching. It is modeled on the
behavior of Paper and built clean-room on wgpu + winit + egui.
A local-first design and whiteboard tool. Projects are folders of pages; each page is an infinite canvas with frames, groups, components and instances, auto layout and constraints, vector paths and booleans, gradients and image fills, rich text, smart guides, and pressure-sensitive ink — plus a whiteboard mode: hand-drawn (rough.js-style) shapes, arrows that bind to shapes and re-route, elbow connectors, sticky notes, a laser pointer and a shape library. Everything autosaves, and exports to PNG, SVG and PDF; Excalidraw files and SVG import.
Clean-room note.
analysis/PAPER_ARCHITECTURE.mddocuments how Paper Desktop 0.5.15 is put together, from a licensed install. The Electron package turned out to be a thin shell around the hosted web editor. paper-rs re-implements behavior only. No Paper code, shaders, icons, fonts or assets are used or committed. The UI and canvas text use Inter 4.1 (SIL OFL 1.1), bundled inassets/fonts/.
paper-rs is an independent, clean-room-style reimplementation. It was reverse engineered from Paper by studying the behavior of the Paper desktop app with REA and Claude Code. It is not affiliated with or endorsed by Paper. No original Paper code or assets are included in this repository.
paper-rs opens on a home screen of your projects (recents grid with thumbnails, New, Import,
and Rename / Duplicate / Move to Trash from each card's ⋯ menu or right-click; restore from
Trash). Each project is a plain folder in ~/Documents/paper-rs/<name>/ holding project.json
and one JSON file per page in pages/. Work is autosaved about a second after each change with
crash-safe atomic writes; files are versioned and older versions migrate on load. Set
PAPER_RS_HOME to use another folder.
A project has any number of pages (Pages list at the top of the left sidebar: + to add, double-click to rename, right-click to duplicate or delete, drag to reorder). Each page is its own infinite canvas with its own undo history and view. Copy and paste works between pages and between projects.
You need Rust 1.95 or newer (rust-version in Cargo.toml; the latest stable is recommended). Install it with rustup.
cargo build --release
./target/release/paper-rs # projects home screen
./target/release/paper-rs --demo # sample planning board (not saved)
./target/release/paper-rs ~/Documents/paper-rs/Plan # open a project folder
./target/release/paper-rs board.paper-rs # open a paper-rs 0.1 documentxcode-select --install # command line tools (linker)
curl https://sh.rustup.rs -sSf | sh
cargo build --release && ./target/release/paper-rs --demoIt uses Metal through wgpu. Shortcuts use ⌘, and trackpad pinch zooms. The macOS target is
type-checked in CI-style (cargo check --target aarch64-apple-darwin) but has not been run on
Mac hardware yet (see Known gaps).
# Debian/Ubuntu runtime libraries (usually already present on desktops)
sudo apt install libxkbcommon-x11-0 libxcb-xkb1 libvulkan1 mesa-vulkan-drivers
cargo build --release && ./target/release/paper-rs --demoIt runs on X11 and Wayland through Vulkan, or GL as a fallback. Shortcuts use Ctrl. File dialogs use the XDG desktop portal.
No display is needed. wgpu renders offscreen, through Mesa lavapipe when there is no GPU:
paper-rs --screenshot ui.png --demo --size 1440x900 --scale 2 # full UI
paper-rs --screenshot home.png --home # projects home screen
paper-rs --export-png out.png PROJECT_DIR --page 0 --scale 2 [--transparent]
paper-rs --export-svg out.svg PROJECT_DIR
paper-rs --export-pdf out.pdf PROJECT_DIR --frames # one PDF page per frame
paper-rs --export out_dir PROJECT_DIR --format png --scope frames # a folder of PNGs
paper-rs --import board.excalidraw # new project, prints its folder
paper-rs serves the Model Context Protocol while it runs, so
agents such as Claude Code and Codex can read and design on the open canvas, the way Paper's
own MCP server works (behaviour notes: analysis/paper-mcp.md). Every tool call runs through
the editor like a user edit: one undo step per call, and the window repaints immediately.
- Streamable HTTP (built into the app):
http://127.0.0.1:29980/mcp. Paper uses 29979, so both can run. Loopback only; requests from browsers (with anOriginheader) and foreignHostheaders are rejected.PAPER_RS_MCP_PORT=NNNNchanges the port;PAPER_RS_MCP=0turns the server off. - stdio:
paper-rs-mcp(built next topaper-rs) relays stdio to the running app. It lists the tools even when the app is closed, and tells the agent to start paper-rs if a call can't reach it.
# HTTP (the app must be running)
claude mcp add --transport http --scope user paper-rs http://127.0.0.1:29980/mcp
# or stdio through the bridge
claude mcp add --scope user paper-rs -- /path/to/paper-rs/target/release/paper-rs-mcp# HTTP
codex mcp add paper-rs --url http://127.0.0.1:29980/mcp
# or stdio
codex mcp add paper-rs -- /path/to/paper-rs/target/release/paper-rs-mcpwhich writes this to ~/.codex/config.toml (either form works):
[mcp_servers.paper-rs]
url = "http://127.0.0.1:29980/mcp"
# command = "/path/to/paper-rs/target/release/paper-rs-mcp"Then ask the agent something like "In paper-rs, create a 390×844 mobile artboard and design a sign-in screen", or "draw a flowchart of our deploy process on a new page, hand-drawn style".
Names and arguments follow Paper's MCP server where paper-rs has an equivalent, so prompts written for Paper work here too.
| Group | Tools |
|---|---|
| Projects & pages | list_resources, open_file, create_file, create_page, rename_pages |
| Read | get_basic_info, get_selection, get_node_info, get_children, get_tree_summary, get_computed_styles, get_jsx, find_nodes, get_fill_image, get_font_family_info, get_guide |
| See | get_screenshot (PNG image content of a node or the page), export (PNG/SVG/PDF files), export_combined_pdf |
| Write | create_artboard, write_html, update_styles, set_text_content, rename_nodes, duplicate_nodes, move_nodes, delete_nodes, finish_working_on_nodes (saves) |
| paper-rs extras | create_shape (rectangles, ellipses, diamonds, stars, stickies, text, lines, arrows bound to shapes), select_nodes, undo, redo |
write_html takes HTML with inline styles: flexbox (display:flex, direction, gap, padding,
alignment, flex-grow, wrap) and block stacking map onto auto layout with CSS's stretch rules;
text gets size, weight, italic, color, line height, letter spacing, alignment and rich-text
runs (<b>, <i>, <span style>); boxes get backgrounds (colors, gradients, images),
borders, radii, opacity and blend modes; <img> takes local paths or data: URIs and <svg>
is imported as vectors. update_styles takes the same CSS as JSON, plus the hand-drawn keys
sketch, roughness, fillStyle, strokeStyle. Node ids look like 3fa9c1:14 (page and
node); pageId lets an agent work on another page without switching the user's view.
cargo test # ~140 tests: unit, scenario, headless GPU, CLI
PAPER_RS_REQUIRE_GPU=1 cargo test # fail (instead of skip) when no GPU adapter exists
cargo test --release --test perf -- --nocapture # 10k-element frame timings- Unit tests cover geometry, vector paths, the rough.js port (compared with real rough.js 4.6.4 output), auto layout and constraints, booleans, rich text spans, the elbow router, formats and migrations, atomic writes, the project store, PDF structure, Excalidraw and SVG import, the palette's fuzzy matching and the shortcut table.
- Scenario tests drive the editor with synthetic pointer and keyboard events:
src/editor/tests.rs(core editing),tests/projects.rs(projects, autosave, pages),tests/figma.rs(groups, components, auto layout, constraints, pen, booleans, rich text, guides),tests/excalidraw.rs(hand-drawn style, arrows, quick-connect, stickies, laser, library),tests/workflow.rs(layers drag, palette, shortcuts),tests/io.rs(export, import, clipboard, CLI),tests/mcp.rs(every MCP tool on a headless session, then an rmcp client over HTTP and through thepaper-rs-mcpstdio bridge). - Headless GPU tests render through wgpu, assert pixels and write the screenshots below. One rasterizes the SVG export with resvg and compares it with the GPU render; one renders the PDF export with pdftoppm when installed.
| Milestone | Screenshot(s) in docs/screenshots/ |
|---|---|
| 1. Local projects | milestone1_home.png, milestone1_trash.png |
| 2. Pages | milestone2_pages.png |
| 3. Figma core | milestone3_figma_core.png, milestone3_canvas.png |
| 4. Excalidraw core | milestone4_whiteboard.png |
| 5. Inspector, palette, shortcuts | milestone5_inspector.png, milestone5_palette.png, milestone5_shortcuts.png |
| 6. Import / export | milestone6_pdf_page.png (PDF rasterized by pdftoppm), milestone6_excalidraw_import.png, milestone6_svg_import.png |
| 7. MCP server | milestone7_mcp.png (a screen written through write_html, captured with get_screenshot), milestone7_mcp_live_xvfb.png (the live app after Claude Code drew into it over the stdio bridge) |
| paper-rs 0.1 | m1_* … m6_*, app_demo.png, x11_window_xvfb.png |
The tools sit in the floating bar at the bottom of the canvas. Select a layer to edit it in the Design panel on the right. The Layers panel on the left shows the tree: click to select, Shift-click to add, double-click to rename, and use 👁 / 🔒 to hide or lock. The Up/Down buttons reorder.
- Draw a frame around existing shapes and it adopts them. Shapes drawn inside a frame become its children, and dragging a layer into or out of a frame re-parents it.
- Top-level frames that contain content act as canvas regions. Drag from their body to marquee-select inside them, and drag the frame by its name label.
- The pencil keeps a constant on-screen width at any zoom. With nothing selected, set width, smoothing and color in the Design panel.
- Hold ⌘/Ctrl while dragging to suspend snapping.
⌘ on macOS, Ctrl on Linux and Windows. Press ? or ⌘/ in the app for the full grouped list
(100+ bindings), or ⌘K to search every command.
| Keys | Action | Keys | Action |
|---|---|---|---|
| V / 1 | Select | ⌘K | Command palette |
| H, or hold Space | Hand (pan) | ⌘Z / ⌘⇧Z | Undo / redo |
| F or A | Frame | ⌘G / ⌘⇧G | Group / ungroup |
| R / 2, O / 4, D / 3 | Rectangle, ellipse, diamond | ⌘⌥G | Frame selection |
| ⇧Y, ⇧S | Polygon, star | ⌘⌥K / ⌘⌥B | Create component / detach |
| L / 6, ⇧L / 5 | Line, arrow | ⇧A / ⌥⇧A | Add / remove auto layout |
| P, ⇧P / 7 | Pen, pencil | ⌥A ⌥H ⌥D / ⌥W ⌥V ⌥S | Align left/center/right, top/middle/bottom |
| T / 8, S | Text, sticky note | ⌥⇧H / ⌥⇧V | Distribute spacing |
| K | Laser pointer | ⌥⇧U S I E | Union, subtract, intersect, exclude |
| E / 0 | Eraser | ⌘E | Flatten |
| 9, ⌘⇧K | Place image | ⌘B / ⌘I / ⌘U / ⌘⇧X | Bold, italic, underline, strikethrough |
| Enter / ⇧Enter | Edit (text, path) / select parent | ⌘⌥H | Hand-drawn style |
| Tab / ⇧Tab | Next / previous sibling | ⇧H / ⇧V | Flip |
| ⌥-drag | Duplicate while dragging | ⌘⌥C / ⌘⌥V | Copy / paste properties |
| ⌥ hover | Measure distances | ⌘R | Rename |
| ⌘= / ⌘- / ⇧0 | Zoom in / out / 100% | ⇧1 / ⇧2 | Zoom to fit / selection |
| PageUp / PageDown | Previous / next page | ⌘\ | Show / hide UI |
Columns 2–4 say whether each product has the feature (✓) and where the behavior was learned:
Paper from its desktop shell and public docs (analysis/PAPER_ARCHITECTURE.md), Figma from
public docs (analysis/FIGMA_NOTES.md), Excalidraw from its MIT source
(analysis/EXCALIDRAW_NOTES.md). The last column is paper-rs: ✅ done,
| Feature | Paper | Figma | Excalidraw | paper-rs |
|---|---|---|---|---|
| Local projects, recents grid, trash | (cloud dashboard) | ✓ (cloud) | (single file) | ✅ Folders in ~/Documents/paper-rs, thumbnails, rename/duplicate/trash/restore |
| Autosave, crash-safe, versioned files | ✓ (cloud) | ✓ (cloud) | ✓ (browser storage) | ✅ 1 s autosave, atomic writes, migration chain (page v1→v3) |
| Pages, infinite canvas per page | ✓ | ✓ | – | ✅ Per-page history and camera, reorder/duplicate/delete |
| Frames with clipping | ✓ | ✓ | ✓ | ✅ |
| Groups | ✓ | ✓ | ✓ | ✅ Bounds follow children, click selects group, double-click enters, scale on resize |
| Components, instances, overrides | – | ✓ | (library only) | ✅ Live sync, per-property overrides, reset, detach, go to main |
| Auto layout (direction, gap, padding, hug/fill/fixed, wrap) | ✓ (flexbox) | ✓ | – | ✅ Drag-reorder in flow, space-between, absolute children |
| Constraints | – | ✓ | – | ✅ Left/right/stretch/center/scale per axis, ⌘ to ignore |
| Pen tool, vector point editing | ✓ | ✓ | – | ✅ Corner/smooth points, handles (⌥ breaks), close, delete, toggle |
| Boolean ops (union/subtract/intersect/exclude), flatten | (roadmap) | ✓ | – | ✅ |
| Gradients (linear, radial) | ✓ | ✓ | – | ✅ Multi-stop, angle, radius; |
| Image fills | ✓ | ✓ | ✓ (image element) | ✅ Fill/fit/stretch/tile, place image (⌘⇧K), drag-and-drop, stored in project |
| Strokes: width, align, dash, caps, joins | ✓ | ✓ | ✓ | ✅ |
| Corner radius (per corner), polygons, stars | ✓ | ✓ | – | ✅ |
| Opacity, blend modes | ✓ | ✓ | ✓ (opacity) | ✅ |
| Rich text (per-range bold/italic/size/colour) | ✓ | ✓ | – | ✅ Plus underline, strikethrough, line height, letter spacing |
| Align / distribute | ✓ | ✓ | ✓ | ✅ ⌥A/D/W/S/H/V, ⌥⇧H/V |
| Smart guides, spacing, measurement | ✓ | ✓ | – | ✅ Edge/center snap, equal spacing, ⌥-hover distances |
| Hand-drawn (rough) style per element | – | – | ✓ | ✅ rough.js 4.6.4 port, verified against rough.js output; sloppiness, fill styles |
| Bound arrows, elbow arrows, quick shapes, sticky notes | – | (FigJam) | ✓ | ✅ Orbit binding that follows shapes, straight/curved/elbow, 5 heads, diamond, quick-connect, stickies |
| Laser pointer, shape library | – | (FigJam) | ✓ | ✅ Fading laser trail; shared library with starter items |
| Inspector, layers drag-reorder, command palette (⌘K) | ✓ | ✓ | ✓ | ✅ Sectioned inspector, tree drag above/below/into, fuzzy palette over actions, pages, layers, library |
| Export PNG / SVG / PDF of selection, frame, page | ✓ | ✓ | ✓ (PNG/SVG) | ✅ Selection, each frame, page or all pages; vector PDF with gradients, images, blend modes; copy as PNG/SVG |
| Import .excalidraw / SVG, copy-paste across projects | – | ✓ (SVG) | ✓ | ✅ .excalidraw scenes, .excalidrawlib libraries, SVG (paths, gradients, images, text), system clipboard between pages, projects and apps |
| Freehand ink with pressure | – | (pencil) | ✓ | ✅ Smoothing, pressure, eraser |
| MCP server for AI agents | ✓ | ✓ (Dev Mode) | ✓ (community) | ✅ Streamable HTTP in the app + stdio bridge; Paper-compatible tool names, write_html, screenshots, whiteboard shapes |
| Multiplayer, cloud sync, plugins | ✓ | ✓ | ✓ | ❌ local-first by design |
- Paper's document model is HTML/CSS. paper-rs uses geometric nodes with flexbox-like auto layout on frames; there are no variables, CSS export or code generation.
- Rendering approximations. Frame clipping is a rectangle (scissor), so rounded frames don't clip their corners. Group opacity multiplies into children instead of compositing the group. Overlay, color dodge/burn, hard/soft light, difference, exclusion, hue, saturation, color and luminosity blend as Normal on the canvas (they are exact in SVG export).
- Booleans are destructive: the result is a new vector path with flattened curves. Gradients are edited in the inspector only.
- Not run on macOS hardware yet. The macOS build type-checks and uses only portable APIs
(Metal via wgpu, winit, rfd), but it has not been launched on a Mac. On Linux, the real
window was exercised under Xvfb; the screenshot is
x11_window_xvfb.png. - Pen pressure. winit 0.30 does not expose tablet pressure for pen events that arrive as
mouse input, which is common with macOS and Wacom tablets. Pressure comes from touch/pen
forcewhen the platform reports it. Otherwise it is simulated from stroke velocity. - Text uses Inter (regular, bold, italic, bold italic) with no shaping, so there are no ligatures, complex scripts or RTL, and no font picker. IME preedit is not displayed (committed text works).
- No rotation. Nodes are axis-aligned boxes; rotated imports are baked into paths.
- Undo granularity. Document renames from the Design panel are not undoable, and the selection is not part of history.
- Performance. Nodes are tessellated once per zoom octave and cached; unchanged frames
reuse the previous item list and GPU buffers, so panning uploads nothing. With 10k visible
nodes a cached frame takes ~3 ms (release,
tests/perf.rs); the first frame at a new zoom octave takes ~140 ms on a CPU. Not tuned for 100k+. - PDF: text is outlined (not selectable); gradient stop transparency uses the first stop's alpha; tiled image fills are drawn as repeated images.
- Import: Excalidraw rotation is baked into paths (text rotation is dropped), bound text inside shapes stays a separate text layer (except sticky notes), and fonts map to Inter. SVG patterns, filters, masks and clip paths are not imported.
- MCP: one project is open at a time, so
fileIdmust name the open project (callopen_fileto switch; the user's window switches too). No design tokens, comments or AI image generation (Paper has them). Moving or duplicating layers between pages isn't supported. Remotehttp(s)images aren't fetched; pass a local path or adata:URI. CSS margin, grid, shadows and transforms are reported back as ignored styles. - Linux file dialogs need an XDG desktop portal. Without one, Save/Open dialogs return nothing. The headless CLI is unaffected.
src/geom.rs vectors, rects, camera
src/vector.rs bezier paths: flatten, hit test, SVG data, shapes, dashes
src/model/ Node / NodeKind / paints / Document arena
src/history.rs transactions, undo/redo
src/layout.rs auto layout, constraints, group bounds
src/ink.rs stroke smoothing, pressure, outline
src/text.rs rich text layout and glyph outlines
src/assets.rs image registry (content-hashed)
src/project/ project store, manifest/page formats, migrations
src/session.rs open project, autosave, thumbnails
src/editor/ tools, structure (groups/components), vector ops, pages, text editing
src/render/ draw ops → cached meshes → wgpu; headless capture
src/io/ PNG, SVG, PDF, export scopes, Excalidraw + SVG import, clipboard,
atomic writes
src/connector.rs arrow bindings, elbow router, arrowheads
src/library.rs shared shape library
src/ui/ home screen, pages, layers, inspector
src/app.rs winit application
src/mcp/ MCP server (rmcp): tools, HTML/CSS mapping, HTTP service
src/bin/paper-rs-mcp.rs stdio bridge to the running app
analysis/ reverse-engineering findings and design (raw dumps are gitignored)
docs/screenshots/ headless renders produced by `cargo test`
site/ the download page (SvelteKit on Vercel); see site/README.md
AGENTS.md workflow for coding agents; its skills live in .agents/skills/
MIT OR Apache-2.0 for the code in this repository. Inter (Regular, Medium, SemiBold) is
© The Inter Project Authors under the SIL Open Font License 1.1; see assets/fonts/OFL.txt.
The agent skills in .agents/skills/ keep their own licenses; see THIRD_PARTY.md.