Hermes PDF Reader

Hermes PDF: Because sometimes, the fastest way to fix a problem is to build the thing yourself.

It started with Adobe Acrobat asking me to log in to open a PDF. I closed the login window out of habit — the app closed with it. When I finally signed in, I was greeted by two sidebars and an AI assistant I hadn't asked for, standing between me and a document I just wanted to read.

So I built Hermes PDF — a desktop reader that does exactly one thing: opens your file and gets out of the way.

The name

Hermes — the Greek messenger god, fast and unencumbered — felt like the right namesake for an app whose entire philosophy is "deliver the thing, skip the ceremony."

What it does

Hermes is a native desktop app built on Tauri, pairing a Rust backend with a lightweight TypeScript frontend and PDF.js for rendering. It supports up to 20 PDFs open at once across tabs, continuous scrolling through pages, smooth inertia-based scroll (via Lenis), and per-tab zoom that remembers exactly where you left off — resize the window and it re-fits automatically, until you take manual control. A native OS menu handles Open and Exit, no custom UI pretending to be something it isn't.

Why it was worth building

This wasn't really about PDFs. It was about noticing a small, specific piece of friction in a daily tool and asking whether the fix was actually hard — it wasn't. The bulk of the build was decision-making under real constraints: Tauri over Electron for a smaller footprint, vanilla TypeScript over a framework because the UI genuinely didn't need one, SvelteKit swapped for plain Svelte+Vite early on once its routing/SSR machinery proved to be dead weight for a single-window desktop app.

Stack: Tauri, Rust, TypeScript, PDF.js, Lenis

Along the way, the project became a crash course in the parts of desktop development that don't show up in a typical web build: native menu APIs, OS-level file associations (registering "Open with Hermes PDF" directly in the Windows right-click menu, not just the submenu), Tauri's capability-based permission system, and the beginnings of a signed auto-updater pipeline.