Programmatic PDF generation with templates

The anatomy of a programmatic template

A robust programmatic PDF workflow requires more than just raw HTML strings. A pdfs.build template unites three critical components into a guaranteed contract:

Three architectural approaches compared

Most engineering teams start with imperative libraries or headless Chrome before switching to programmatic template engines. Here is how they compare in production:

Programmatic render recipes

One HTTP call sends your JSON data payload and streams the compiled binary PDF response immediately:

// TypeScript / Node.js
import fs from "node:fs/promises";

const response = await fetch("https://api.pdfs.build/v2/organizations/org_main/templates/invoice-standard/render", {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${process.env.PDFS_BUILD_API_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    data: {
      invoice_number: "INV-2026-0842",
      date: "2026-09-21",
      customer: {
        name: "Acme Logistics Corp",
        tax_id: "US-9482104",
      },
      items: [
        { description: "Priority Cargo Freight", quantity: 2, unit_price: 450.00 },
        { description: "Handling & Customs Clearance", quantity: 1, unit_price: 120.00 },
      ],
      currency: "USD",
    },
  }),
});

if (!response.ok) {
  const error = await response.json();
  throw new Error(`Render failed: ${error.message}`);
}

// Raw PDF buffer ready to store in S3, email to customer, or stream to client
const pdfBuffer = Buffer.from(await response.arrayBuffer());
await fs.writeFile("invoice.pdf", pdfBuffer);

Three ways to create your template

• A

  Pick from the 165+ Production Template Gallery

  Every design in the template gallery is a compiled Typst document with schema and variables already wired. Pick an invoice, report, or certificate and adjust in minutes.

• B

  Co-design with the AI Chat Agent

  Describe your document requirements in natural language. The AI agent writes Typst layout code, generates the matching JSON schema, and checks compilation on every revision.

• C

  Import Existing Word (.docx) Files

  Upload a .docx file and convert it into a faithful Typst template, then define dynamic data slots. Learn how in our Word-to-API walkthrough.

Frequently asked questions