Personal Project — Case Study

Rustle

An offline ebook reader with built-in AI text-to-speech. Import any ebook, convert it to audiobook instantly—with synchronized word highlighting that follows along.

TypeSide Project
RoleDesign & Development
Built WithCursor AI
StatusFully Offline
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Audiobooks Shouldn't Be This Hard

I love reading, but I don't always have time to sit with a book. Audiobooks are the obvious solution—except they come with frustrating limitations that shouldn't exist in 2025.

Pay Twice for the Same Book

Already own the ebook? Too bad—audiobook is a separate purchase. Same content, double the cost.

Limited Selection

That niche technical book or indie author? No audiobook available. Major publishers only.

Robotic TTS Options

Existing text-to-speech sounds mechanical and unpleasant. Not something you'd listen to for hours.

Cloud Dependency

Most TTS services require internet. No connection? No listening. Your library shouldn't need WiFi.

100%
Offline
Books Supported
0
Subscriptions
1
Weekend Build

What Rustle Does

A focused tool that does one thing exceptionally well—turns your ebooks into listenable audiobooks without compromises.

01
Kokoro AI Voice
Built on Kokoro TTS—a natural-sounding AI voice that doesn't fatigue your ears. Expressive, clear, and pleasant for extended listening sessions.
02
Word-Level Highlighting
Follow along as Rustle reads. Each word highlights in sync with the voice—perfect for language learning, accessibility, or maintaining focus.
03
Fully Offline
No internet required after initial setup. Your books, your voice engine, your device. Works on planes, in remote areas, anywhere.
04
Import Any Ebook
EPUB, PDF, MOBI—bring your existing library. No vendor lock-in, no format restrictions. Your books, instantly listenable.

See It In Action

Watch Rustle transform an ebook into a synchronized audiobook with word-level highlighting.

Simple by Design

No complicated setup. Import, convert, listen.

01

Import

Drop your ebook into Rustle. EPUB, PDF, MOBI—whatever you have. The book is parsed and prepared for conversion.

02

Convert

Kokoro AI processes the text locally on your device. No cloud processing, no data leaving your machine.

03

Listen

Read along with synchronized highlighting, or close your eyes and listen. Pause, resume, adjust speed—full control.

Built With

Modern tools for a modern reading experience.

Kokoro TTS
AI Voice Engine
Coqui's open-source text-to-speech model that runs entirely offline. Provides natural, expressive voices perfect for long-form audiobook listening.
Cursor
AI-Assisted Development
The entire app was built through conversational development. I described features, Cursor generated code, and we iterated together.
Electron
Desktop Application
Cross-platform desktop framework that allows Rustle to run natively on Windows, macOS, and Linux with a single codebase.
EPUB.js
Ebook Parsing
JavaScript library that parses EPUB files, extracts text content, and handles chapter navigation for seamless ebook import.

Vibe Coding with Cursor

Rustle was built using "vibe coding"—a conversational approach to development where I described what I wanted and iterated with Cursor AI to bring it to life.

Designer Meets Developer

As a UX designer, I could articulate exactly what the experience should feel like. Cursor handled the implementation details—parsing ebook formats, syncing audio timing, managing state.

This isn't about not knowing how to code. It's about removing friction between idea and execution. I could focus on the experience while AI handled the boilerplate.

The result? A functional prototype in a weekend that would have taken weeks with traditional development.

2
Days from idea to working prototype
50+
Iterations with Cursor
0
Lines of code written from scratch

What I Learned

"The best tools are the ones you build because nothing else does exactly what you need."

AI Democratizes Building

Cursor let me ship a functional app without being a developer. The barrier between "designer who can prototype" and "designer who can ship" is collapsing. What used to require weeks of learning frameworks and debugging now happens through conversation. I could focus on the experience—how the highlighting should sync, how the voice should feel—while AI handled the implementation details.

Offline-First Still Matters

In an always-connected world, there's something powerful about tools that work anywhere. No accounts, no subscriptions, no dependencies. Rustle works on a plane, in a remote cabin, or in a country with spotty internet. This constraint forced better design—everything had to be self-contained, efficient, and reliable. The result is a tool that respects your privacy and your environment.

Scratch Your Own Itch

The best side projects solve problems you personally have. Rustle exists because I wanted it to exist—and that made every design decision clearer. When you're building for yourself, you know exactly what's missing. No user research needed, no feature prioritization debates. Just pure focus on solving your own problem in the best way possible.

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