Print-Grade CSS Fidelity For A Serverless HTML-To-PDF Engine
Folio converts HTML to PDF entirely in the browser via WebAssembly with no server and no signup, reaching 827 GitHub stars from developers who want documents generated without sending data anywhere, but its issues are a checklist of the print-CSS primitives multi-page documents require: superscript and subscript ignore baseline shift, percentage border-radius renders square, and position fixed and per-page margins are silently ignored across pages. Developers want client-side PDF generation that respects real print CSS. The wedge is a WASM HTML-to-PDF engine with genuine multi-page print-CSS fidelity, the gap that sends devs back to headless Chrome.
Problem Statement
A developer needs to generate an invoice or report PDF in the browser without uploading customer data to a server, so they adopt a WASM engine, but superscripts sit on the wrong baseline, percentage border-radius renders square, and a fixed masthead and per-page margins are dropped across pages. The output is not print-grade, so they fall back to a server-side headless Chrome pipeline and lose the privacy and cost benefit.
The Idea
A serverless WebAssembly HTML-to-PDF engine with faithful multi-page print-CSS support so developers generate documents client-side without headless Chrome.
Why Now
Privacy and cost pushed developers to want client-side document generation in 2026 instead of server-side headless Chrome, and Folio's traction shows the appetite, but its print-CSS gaps on baseline shift, border-radius, and multi-page primitives show that fidelity, not the WASM concept, is what determines whether teams can actually ship it.
Target User
Developers generating invoices, reports, and documents who want client-side PDF without a server
Target Market
Document generation and HTML-to-PDF developer tooling
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