A modern notebook app for Linux for writing with pen, touch and mouse
Written in Rust with wgpu, winit and egui.

English · Deutsch

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ink-notes stores handwriting as vectors, can recognize shapes, imports PDFs for annotation, inserts images and text boxes, and exports everything again as PDF, PNG or SVG. Saving happens automatically in the background.

It is mainly tested on Zorin OS 18 / Ubuntu 24.04 (Wayland and X11).

The interface is available in English and German; ink-notes follows the system language, and you can switch it in the ☰ menu under "Sprache / Language".

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Features

Writing and drawing

• Four pens in the toolbar, each with its own color and width (0.15–5 mm, pressure-sensitive). When you change a pen's color or width, it remembers that – also across restarts. Highlighter (semi-transparent, 4–8 mm) in four colors; it does not get darker within one stroke, only a new stroke covers more strongly.
• Custom colors: Every color in the toolbar (pens, highlighter, text) can be changed – tap the selected color again and pick a preset or any shade with 🎨. The toolbar remembers the colors. They look the same on screen as in PDF and image exports.
• Two-stage smoothing: While you write, a 1€ filter removes jitter and the line appears immediately. When you lift the pen, the stroke is refined: corners (bends over 65°) are kept and drawn round, the pressure curve is smoothed, redundant points are dropped and the ends become round.
• Pressure curve adjustable to your pen in the ☰ menu (softer/harder, threshold against base noise).
• Pen buttons can be assigned in the ☰ menu: erase (default), select, highlighter, pen or nothing – active while the button is held. Each button appears there after it is pressed for the first time.
• Eraser with three modes: whole strokes, only the part you wipe over (partial stroke), or highlighter only. The back end of the pen erases too.
• Virtual ruler (L): move it, rotate it by its handle (snaps to 15°); strokes along an edge become straight.
• Make space (↕ in the toolbar): tap the page and drag down – everything below moves along, also on the following pages. Whatever would slide past the end of a page continues on the next one; missing pages are appended. Dragging up closes empty space. Undo reverts it in one step.

Shape recognition

• Shape tool (S/F) or hold at the end of a stroke (keep still for more than 400 ms): the sketch is replaced by a clean shape in the width of the current pen or highlighter.
• Recognized shapes: lines, arrows, circles, ellipses, rectangles, triangles, rhombuses, polygons, coordinate systems (L shape), axis crosses (a "+" in one stroke or two crossing straight lines, arrowheads on all four ends) and octahedra (sketch as a 3D solid).
• Recognition is purely geometric (arc length, Douglas-Peucker, circle fitting), without machine learning. Not everything is recognized – whatever does not fit stays handwriting.

Selecting and editing

• Selection tool (V): tap or drag a frame, then move, scale by the corners, rotate by the handle, or rotate by 90° with R. Works with mouse, finger and pen.
• Recolor the selection with the palette, copy/paste (Ctrl + C/V), delete (Del).
• Ctrl + C also puts the selection on the clipboard as an image, e.g. for chat or email.
• Undo/redo (Ctrl + Z/Y) for all changes, per page.

Text, images and PDFs

• Text tool (T): tap the page and type – regular or code font (fixed character width, Tab indents), 8–36 pt, line wrapping at the box edge. Tap existing text to change it, Esc finishes. Text boxes can be moved, rotated and scaled like images. Text copied in other programs becomes a text box with Ctrl + V.
• Images (PNG, JPEG, GIF, WebP, BMP) via Ctrl + I, from the clipboard, or by dragging them into the window.
• Paste with a finger: Pressing the page with a finger for half a second opens a "Paste" menu – a screenshot, copied text or copied objects land exactly at that spot.
• Import PDF (☰ menu): Every PDF page becomes a notebook page with the PDF page as background. Portrait pages become A4; landscape pages (e.g. slides) get a landscape page without an empty strip below. When you zoom in, PDF pages are re-rendered more sharply.

Pages and view

• Backgrounds: blank, squared (5 mm), ruled (7.5 mm), dot grid (5 mm). The color of squares, lines and dots is selectable (light, medium, strong, blue, green) and also applies to exports.
• Paper color on screen: white, cream, dark gray, black; on dark paper, dark pen colors can optionally be brightened. Saving and exporting always use white paper.
• Continuous scrolling, endless canvas or fixed pages, per notebook: chosen when creating a notebook (default: continuous; or endless) and switchable in the ☰ menu – where fixed pages are available too (page by page with arrows in the toolbar). In continuous mode the pages hang seamlessly below each other with a dark line marking the boundary. A quick swipe keeps gliding, and the scrollbar on the edge opposite the toolbar jumps through long PDFs with the page number shown. Writing in the bottom fifth of the last page adds a new page automatically. Endless is a single borderless canvas you can write on in every direction; the PDF export only contains the area you used.
• Insert and delete pages: ➕ in the toolbar inserts an empty page after the current one. Delete it in the ☰ menu (with confirmation); the most recently deleted page can be restored there while the app is running.
• Zoom from 25 % to 1000 % (Ctrl + mouse wheel, two fingers, Ctrl + +/-/0), pan with the middle mouse button, Space + drag or one finger.
• Pages can be appended or inserted right after the current page, and given page titles; the page overview shows thumbnails or a table of contents. Page titles become bookmarks in the PDF.
• Toolbar can be docked left or right (for left- and right-handed use).

Notebooks and saving

• Create, rename, switch and delete multiple notebooks (deleted ones go to the trash first and can be restored).
• Folders for notebooks, nested as deep as you like (e.g. Semester 3 › Math): create, rename, delete (the content moves up one level), and move notebooks and folders (with their content) with 📂. New notebooks are created in the folder that is currently open.
• Automatic saving in the background: 1.5 seconds after the last change, and at least every 10 seconds while you keep writing. Drawing is never interrupted.
• Every file is first written completely to a temporary file and then replaced – a crash while saving never leaves a half-written file.
• When closing (window or Ctrl + Q) and when switching notebooks, everything pending is written before continuing. If that fails, the app stays open and offers to retry or to make an emergency backup.
• Ctrl + S saves immediately. The dot on the ☰ button shows the state: green = saved, orange = changes pending, yellow = saving, red = error.

Export

• PDF (Ctrl + E) to ~/Documents/<title>.pdf: strokes and shapes as vectors, text boxes as real, searchable text, imported PDF pages as vector background, page titles as bookmarks.
• Single page as PNG (with or without background) or SVG via the ☰ menu.

Input devices

• Pens via the Wayland or X11 tablet protocol (pressure, eraser end, side button).
• While the pen touches the screen or hovers nearby, touches by the hand are ignored.
• Fingers: scroll and zoom by default; drawing with a finger can be enabled in the ☰ menu.

Updates

• The app checks Gitea for new versions and installs them on request. It only installs when the Minisign signature and the SHA-256 checksum match (details below).
• As a Flatpak, ink-notes does not look for updates itself; they come through the software manager (flatpak update).

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Installation

Packages are available under Releases as .deb and .AppImage (x86_64). <version> stands for the version number, e.g. 0.30.2.

# Debian package (Zorin OS 18 / Ubuntu 24.04)
sudo apt install ./ink-notes_<version>_amd64.deb

# or AppImage
chmod +x ink-notes_<version>_x86_64.AppImage
./ink-notes_<version>_x86_64.AppImage

Notes:

• Requires glibc >= 2.39 (Ubuntu 24.04, Zorin OS 18) and a graphics driver with Vulkan or OpenGL.
• If the AppImage reports an error about libfuse.so.2, either install sudo apt install libfuse2t64 or start it with --appimage-extract-and-run.

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Keyboard shortcuts

Action	Key / gesture
Draw	Pen tip, left mouse button (finger, if enabled)
Erase	toggle with E, right mouse button, pen eraser end or side button
Pen in black / blue / red	B / U / R
Shape tool	S or F
Selection tool	V
Text tool	T, then click on the page; Esc finishes typing
Ruler on/off	L
Change background	G
Rotate selection by 90°	R (with a selection)
Copy / paste	Ctrl + C / Ctrl + V
Delete selection	Del or Backspace
Undo / redo	Ctrl + Z / Ctrl + Y or Ctrl + Shift + Z
Insert image	Ctrl + I
Scroll	mouse wheel (Shift = horizontal), one finger
Zoom	Ctrl + mouse wheel, two fingers, Ctrl + + / Ctrl + -
Reset zoom	Ctrl + 0
Pan	middle mouse button or Space + drag
Next / previous page	Page Down or N / Page Up
First / last page	Home / End
Save now	Ctrl + S
Export PDF	Ctrl + E
Close menus, clear selection	Esc
Quit (saves first)	Ctrl + Q or close the window

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Development

Requirements

• Rust 1.92 or newer (rustup update stable)
• Vulkan or OpenGL driver (e.g. mesa-vulkan-drivers)
• X11/Wayland libraries: libx11-dev, libxcursor-dev, libxrandr-dev, libxi-dev, libxkbcommon-dev

Build, run, test

git clone https://gitea.pansi.eu/harald/ink-notes.git
cd ink-notes
cargo run --release          # or ./run.sh
cargo test                   # unit and integration tests

CI additionally checks cargo fmt --check and cargo clippy --all-targets -- -D warnings.

New code comments and commit messages are written in English; older code and history still contain German.

Project structure

src/
├── main.rs         # Event loop (winit), mouse, touch and pen input, control flow
├── lib.rs          # Library exports (for tests)
├── canvas.rs       # wgpu rendering: paper, patterns, images, ink, neighboring pages
├── shader.wgsl     # Vertex and fragment shaders
├── viewport.rs     # Camera (zoom, pan), page stack of the continuous view, swipe momentum
├── filter.rs       # 1€ filter against jitter
├── spline.rs       # Catmull-Rom splines, corner preservation, triangle strips
├── geometry.rs     # Shape recognition (Douglas-Peucker, circle fitting, …)
├── selection.rs    # Selection, handles, move/rotate/scale
├── ruler.rs        # Virtual ruler
├── text.rs         # Text boxes: layout, line wrapping, rasterization
├── background.rs   # Paper colors, pattern colors, squares/lines/dots
├── image_layer.rs  # Textures for images, PDF pages and text
├── assets.rs       # Images and PDFs in the notebook folder
├── pdf_doc.rs      # Reading and rendering PDFs (hayro)
├── pdf_merge.rs    # Underlaying imported PDF pages on export
├── document.rs     # Data model: notebook, pages, strokes, page sizes
├── history.rs      # Undo/redo
├── storage.rs      # Loading/saving (atomic), notebooks, trash
├── library.rs      # Notebook folders (library.json)
├── autosave.rs     # Saving in the background
├── export.rs       # PDF export (printpdf)
├── page_export.rs  # Page as PNG/SVG, selection as image
├── file_picker.rs  # Built-in file picker
├── settings.rs     # Settings (~/.config/ink-notes/ui.json)
├── platform.rs     # Wayland/X11 detection
├── updater.rs      # Updates from Gitea (signature and checksum verification)
└── ui.rs           # Interface (egui): toolbar, menus, dialogs

More in docs/ARCHITECTURE.md; the storage format is described in docs/FILE_FORMAT.md.

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Building and publishing releases

./scripts/build-release.sh          # .deb, .AppImage and SHA256SUMS.txt in target/

Releases are published by Gitea Actions (.gitea/workflows/release.yaml) as soon as a tag vX.Y.Z is pushed: tests, build packages, sign, create the release. To do it manually: GITEA_TOKEN=… ./scripts/publish-gitea-release.sh.

Flatpak

The manifest is in packaging/flatpak/ (runtime org.freedesktop.Platform 26.08, Rust from the SDK extension rust-stable). Build and install locally:

flatpak-builder --user --install --force-clean target/flatpak-build packaging/flatpak/eu.pansi.ink-notes.yml
flatpak run eu.pansi.ink-notes

After every change to Cargo.lock, packaging/flatpak/cargo-sources.json must be regenerated with the flatpak-cargo-generator (python3 flatpak-cargo-generator.py Cargo.lock -o packaging/flatpak/cargo-sources.json). In the sandbox, ink-notes may read Pictures, Downloads and Desktop and export to the Documents folder; the notebooks live under ~/.var/app/eu.pansi.ink-notes/.

Setting up the release signature (once)

The app only installs updates with a valid Minisign signature. Signing uses rsign2 (cargo install rsign2 --locked). Generate a key pair without a password (it is only used as a CI secret):

rsign generate -W -p ink-notes.pub -s ink-notes.key

1. Put the second line of ink-notes.pub (starting with RW) into src/updater.rs as UPDATE_SIGNING_PUBLIC_KEY.
2. Store the content of ink-notes.key in Gitea under Repository → Settings → Actions → Secrets as MINISIGN_SECRET_KEY.
3. Keep ink-notes.key offline. If it is lost, existing installations can no longer verify updates.

rsign generate -W encrypts the key with an empty password; the minisign program (e.g. Ubuntu package 0.11) cannot read it without a terminal, which is why the script and CI sign with rsign. In CI the signature is mandatory (INK_NOTES_REQUIRE_SIGNATURE=1), and the script checks that the secret key matches the built-in public key.

CI runner (act_runner)

The workflow runs on the label ubuntu-latest. It must be mapped in the runner's config.yaml, e.g.:

runner:
  labels:
    - "ubuntu-latest:docker://catthehacker/ubuntu:act-latest"

If a job stays at "Waiting to run": is the runner online (Settings → Actions → Runners) and does the label match runs-on? The workflow only uses sudo when the runner does not run as root.

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Update security

1. Signature: Every release contains SHA256SUMS.txt.minisig. The app downloads SHA256SUMS.txt and the signature before the package and verifies them against the built-in public key (minisign-verify). Without a valid signature, nothing is installed.
2. Checksum: The SHA-256 of the downloaded package must match the entry in the signed list, otherwise the file is deleted.
3. HTTPS only: Download links and redirects must be HTTPS too. On redirects to a different server, the Authorization header is not sent along.
4. Dedicated download folder: ~/.cache/ink-notes/updates (permissions 0700); file names with path separators, .. or control characters are rejected.
5. AppImage replacement: The new file is created next to the old one, the old one is kept as .bak and then replaced with rename – the running file is never overwritten.

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Contributing

Bug reports, ideas and contributions are welcome – preferably as an issue on Gitea; GitHub is a mirror. Issues may be written in English or German. Details in CONTRIBUTING.md; please report security vulnerabilities privately as described in SECURITY.md. The Code of Conduct applies.

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License

MIT, Copyright © 2026 Harald Pansi.