PDFKit
PDFKit is a free, open-source JavaScript library for generating PDF documents programmatically in Node.js and in the browser, using an imperative drawing API — text, shapes, images, and vector graphics are placed on the page through direct method calls (`doc.text()`, `doc.image()`, `doc.rect()`) rather than a template-merge model, giving full layout control at the cost of more code for complex documents compared to a template-based tool.
It supports embedding custom fonts (including Unicode/non-Latin scripts), vector and raster images, multi-page documents with automatic pagination, and basic PDF features like outlines/bookmarks and encryption. Because it runs entirely in-process with no external service call, there's no per-document cost, rate limit, or network dependency — a meaningful advantage for high-volume document generation (receipts, invoices, reports) where sending every document to a third-party API would be slow or expensive.
For Nigerian developers building a Node.js backend that needs to generate invoices, receipts, or reports on the fly, PDFKit is a common default choice specifically because it's free, self-contained, and has no usage-based billing — the tradeoff versus a template-based service like Adobe Document Generation API is that non-technical team members can't edit the document layout themselves; every layout change requires a code change.