Blog
Guides, product updates and engineering notes from the Transactional team.
How to Add a Watermark to a PDF
How to add text or image watermarks to generated PDFs using CSS overlays in your HTML template — no post-processing library, no extra step.
Kevin · June 22, 2026
How to Generate PDFs from a Next.js App (App Router)
Client-side PDF libraries break on SSR. Puppeteer crashes on Vercel Edge. Here is the correct pattern for PDF generation in a Next.js App Router app.
Kevin · June 21, 2026
How to Generate PDFs in a Ruby on Rails App
Wicked PDF and Prawn are getting old. Here is how to generate PDFs in a Rails app with a simple API call — no wkhtmltopdf binary, no layout DSL to learn.
Kevin · June 20, 2026
PDF Generation API Comparison: Transactional.dev vs DocRaptor vs PDFShift vs Gotenberg
An honest comparison of PDF generation APIs in 2026 — pricing, features, template systems, self-hosted vs managed, and which fits which use case.
Kevin · June 19, 2026
How to Generate PDFs in PHP (Laravel, Symfony)
DomPDF and TCPDF are painful to maintain. Here is how to generate production-quality PDFs in Laravel and Symfony with a single API call — no binary dependencies.
Kevin · June 18, 2026
How to Generate PDFs from a Python App
Replace WeasyPrint, ReportLab, and wkhtmltopdf with a single requests.post() call. PDF generation examples for Django, Flask, and FastAPI.
Kevin · June 17, 2026
How to Build a Document Automation Pipeline for SaaS
Design a clean document automation pipeline: events, template selection, variable mapping, PDF generation, and delivery. Full architecture walkthrough.
Kevin · June 16, 2026
How to Handle Multi-Page PDFs with Dynamic Content
Master CSS page breaks, repeating headers, and Handlebars loops to generate clean multi-page PDFs from dynamic data.
Kevin · June 15, 2026
How to Generate a PDF Certificate of Completion
Build a dynamic PDF certificate generator with HTML templates and a simple API call. Perfect for courses, events, and training programs.
Kevin · June 14, 2026
How to Version and Audit PDF Documents in Production
Build an audit trail for every PDF you generate. Store document versions, replay any document, and prove exactly what was sent to whom.
Kevin · June 13, 2026
PDF Generation in a Serverless Environment (Vercel, AWS Lambda)
Why Puppeteer and Chromium fail in serverless environments and how to generate PDFs with a simple API call from Vercel and AWS Lambda.
Kevin · June 12, 2026
How to Build a "Download as PDF" Button in Your SaaS
The complete guide to wiring a download-as-PDF feature in your SaaS — backend endpoint, API call, signed URL, and download response, step by step.
Kevin · June 11, 2026