Every PDF annotation tool we tried felt too mechanical. The brushes were too perfect, pressure input was ignored, and the whole experience was built around highlighting text — not drawing freely. For someone who uses a drawing tablet daily, none of them felt right.
So we built LeedPDF: a lightweight, open-source PDF annotation tool that feels more like sketching on paper than clicking through menus.
Drawing First
LeedPDF has a custom drawing engine with pressure-sensitive strokes and a natural brush feel. Freehand drawing, shapes, text annotations, sticky notes — all designed with minimal UI distraction so the document stays front and center.
It supports drawing tablets properly. Pressure affects stroke width the way you'd expect. The brush doesn't feel synthetic. That's the difference between a tool built for drawing and one that added drawing as an afterthought.
SvelteKit + Tauri
We built LeedPDF with SvelteKit for the interface and Tauri for the desktop app. The web version runs entirely in the browser — no server, no uploads, no accounts. The desktop version gives you the same experience outside the browser, with a lightweight footprint.
Both versions work offline. Your files never leave your device. No logins, no syncing, no tracking.
Privacy Is the Default
Most PDF tools want your documents on their servers. We didn't want that. LeedPDF processes everything locally. Your PDFs stay on your machine, period. That constraint shaped the entire architecture — and we think the product is better for it.