A browser-based expressive drawing tool. As you draw, Nekudot remembers every point and weaves faint lines between nearby ones - so a single gesture blooms into a web of its own. Inspired by mrdoob's Harmony.

🎨 Open the tool online → 🏠 Home → · 📖 About & usage book →

Most brushes only lay down the pixels under your cursor. Nekudot also keeps a point cloud - a "memory map" of everywhere your strokes have been. While you draw, a connecting brush looks up the neighbours of each new point in that cloud and draws lines between them. Hundreds of faint, overlapping lines accumulate into the soft, sketchy, spider-web texture that Harmony made famous.

Because the connections come from a shared, persistent cloud, strokes relate to each other: new marks reach back toward old ones, and the drawing grows as a single connected structure rather than a stack of independent lines.

• Connecting brushes - Round & Handfree bloom into webs; the mark builds up at a steady rate however fast you draw (tuned to match Harmony).
• Grouped connections - pick a style from the navbar combo: Classic (Sketchy, Web, Shaded, Chrome, Longfur - ports of Harmony's brushes), More (Fur, Lace, Arc) and your own Custom presets. The gear opens per-style dials (density, reach, opacity, line shape, dash, arc, stipple…).
• Custom presets - save a look you like (dials + line opacity), update or branch off an existing one, and import / export presets as .preset files to share or back up (validated on import, merged by name).
• Grid brushes - Dots, Lines and Ellipse stamp patterns at grid intersections.
• Shape brushes - Squares & Circles size themselves to your speed.
• Layers - multiple canvases with opacity, drag-to-reorder, duplicate and delete.
• Memory maps - top-level point clouds you can read from / write to independently.
• Even, uniform strokes - faint lines composite through a wet-stroke buffer, so a stroke lands at one flat opacity with no dark dots at sample joints.
• Transparent background - toggle the canvas background off for PNGs with alpha.
• Save, load & share - export a flat PNG (or share it via the Share menu), or a .nekudot archive you can reopen and keep editing.
• Runs entirely in the browser - your work is stored locally (IndexedDB); nothing is uploaded.

Requires Node.js 18+ and npm.

git clone https://github.com/barakbl/nekudot.git
cd nekudot
npm install
npm run dev      # start the Vite dev server (prints a local URL)

Open the URL Vite prints (usually http://localhost:5173) to use the app. The info site and usage book are served alongside it at /about.html and /book/.

npm run build    # production build into dist/
npm run preview  # preview the production build
npm test         # run the Vitest test suite
npm run smoke    # run the headless smoke test

build.sh produces one self-contained, minified app/index.html (JS + CSS inlined). It writes into docs/ by default (the GitHub-Pages site folder), so the single-file app sits next to the landing pages (index.html, about.html) and book/ - ready to host the whole site statically, with the landing page at the site root and the app at /app/:

./build.sh           # writes ./docs/app/index.html
./build.sh out-dir   # or a directory of your choice

• Usage book - how every brush, layer and map works.
• Memory maps - the connecting idea, in depth.
• Developer docs - architecture and writing a brush.

The same docs live in this repo under docs/ (about.html and book/).

The central idea - turning each stroke into a web by drawing lines between nearby points - is Ricardo Cabello's (mrdoob), from his Harmony sketch tool. Nekudot is an independent reimplementation of that idea in TypeScript, and several of the Classic web styles - Sketchy, Web, Shaded, Chrome and Longfur - are direct ports of Harmony's brushes of the same names. Harmony is © 2010 Ricardo Cabello, released under the GPL (v3 or later); the concept and those brushes are his, and full credit goes to him. Nekudot matches that license (see below).

Contributions from developers and artists are both welcome. See CONTRIBUTING.md for how to set up, branch and open a pull request, and please read our Code of Conduct - by taking part you agree to follow it.

Copyright (C) 2026 Barak Bloch

Nekudot is free software, released under the GNU General Public License, version 3 or later. You're free to use, study, share and modify it under the terms of the GPL v3+. This matches Harmony (© 2010 Ricardo Cabello, GPL v3+), from which several web styles are ported. See LICENSE and AUTHORS.

We don't track anything you draw or make - your work stays in your browser, and Nekudot has no accounts and no server for it. The only thing measured is traffic: the website and the app use Umami to count anonymous page views - rough visit counts and referrers only, with no cookies, no personal data and no cross-site tracking or fingerprinting. Because it sets no cookies and stores no personal data, it needs no cookie-consent banner and is designed to comply with the GDPR.