What if every bookmark had a secret link to the pages it lives in? That’s the idea behind Dogear: transforming plain ISBNs into one-of-a-kind bookmarks. It’s maths, art, and a dash of whimsy—all pressed neatly between the pages.
The Dogear project is my way of turning book metadata into physical art. Each book gets its very own bookmark design — no two books look alike. For special collections, like Man Tech’s library, I can even weave in custom touches.
For the Man Tech library, I’ve created bookmarks that echo the Man Group logo. The unique pattern on each bookmark is a mathematical pattern called a Voronoi diagram based on a numerical seed from the book's ISBN. Since the ISBN is a unique number assigned to each edition this means every title has a fingerprint all its own: identical copies share a design, but every different book stands out.
The full bookmark is made from 4 layers, made using a cricut to cut and plot most of the design. Curious to see the full treatment? Check out all four layers for the book Advanced Unix Programming.
The design
Voronoi diagrams are a favorite in computational geometry: they’re orderly, mathematical, and visually striking. A quantitative hedge fund like Man Tech seemed like the perfect home for that mix of maths and beauty.
Each ISBN acts as the seed for the algorithm, so the pattern is tied forever to the book. It’s deterministic: give me the ISBN, and I can regenerate the same design every time. Think of it as a bit of cryptographic flair for your bookshelf.
The border and top flourish borrow from the Man Group logo, making the bookmarks clearly part of the Man Tech library. On the back, I balanced the QR code with a printed echo of the logo at the top—otherwise the weight of the code would steal the whole show.
To soften the hard geometry, I set the lettering on the back in Mistral. It adds a handwritten, human touch against the algorithmic front pattern and the grid of the QR code.
Tools and resources
This was my first project using a Cricut cutting machine. Their "Design Studio" software seriously lets down their hardware. The clean lines of Voronoi edges translated well to the hardware's precision cutting, making the abstract maths tangible in paper.
I generate the Voronoi diagrams using the excellent Voronoice crate by Andre Esteve.
If you'd like to dive deeper, the Dogear project page explains how the whole system takes book metadata and turns it into bookmark files.