Building a PDF Toolkit That Never Touches a Server

Every PDF tool follows the same pattern: upload your file, wait, download the result. That server round-trip exists because PDF processing is genuinely expensive — parsing a file format never designed to be edited, re-encoding pages, running compression. Doing that in a browser tab used to mean either a thin wrapper around a server API, or nothing at all.

That's changed. WebAssembly-compiled versions of real PDF libraries are fast enough now to run entirely client-side, and building DeskRamp meant figuring out what that actually takes inside a Chrome extension, not just a regular web page.

The CSP wall

Manifest V3 extensions get a strict default Content Security Policy, and WebAssembly needs an explicit exception to run at all:

"content_security_policy": {