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20 April 2026 · 2 min read

foldly.eu: why I'm building yet another PDF tool

foldly is my small set of PDF tools: free, ad-free, no login, processed locally in the browser. Why it had to exist and what's under the hood.

foldlyPDFWebAssemblyNext.jsPrivacy

If you work with PDFs, the routine is familiar: merge files, split, rotate pages, occasionally compress. The typical online tools that do this all look the same: aggressive ads, three-layer cookie banners, an annoying “Pro” upsell and, worst of all, your file ending up on someone else’s server. For sensitive documents that’s a no-go.

That’s why I built foldly.

What foldly is

foldly is a small web app with the PDF tools I actually use myself, currently a Phase 1 MVP at foldly.eu.

Three things matter to me:

How it works

The client-side operations rely on pdf-lib and pdfjs-dist, both well-established JavaScript libraries. PDFs can be read, recombined and written entirely in the browser. No server, no upload, no tracking.

The frontend is Next.js 16 with the App Router, React 19 and Tailwind 4. The hosting stack on a small VPS is intentionally pragmatic: Caddy as a reverse proxy, Node for the application, plus LibreOffice, Tesseract and Ghostscript for the planned server tools.

Pageviews are counted anonymously: no IP addresses, no cookies, no third-party analytics. That’s enough to know whether anyone uses the thing.

Why I’m building this at all

A few honest reasons:

  1. My own need. I wanted a tool I’d trust to upload an NDA to.
  2. Keep my hands dirty. My day job is strategy, architecture and people. Building things on the side keeps the bridge to the technology intact, which makes me a better partner in estimation and architecture conversations.
  3. A good playground for modern frontend topics. Next.js App Router, React Server Components, WASM, PDF pipelines: half-touching these at work isn’t enough.

Status and roadmap

foldly is in a Phase 1 MVP. The client-side tools work; server-side tools (Office conversion, OCR, compression) are in progress. After that, maybe an optional account system, but never a forced login.

If you’d like to try it: foldly.eu. Feedback via the contact form is very welcome, especially if something hangs or a file refuses to process.

David Hirsekorn

David Hirsekorn

Manager Microsoft & Community Lead Modern Work. Writes here privately about leadership, AI, Modern Work and processes as well as the tools built in the evenings.

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