Comment by xiljin

Our rails app generates dozens of accounting related reports on the fly in HTML and we use Flying Saucer to generate a PDF version -

https://github.com/flyingsaucerproject/flyingsaucer

To help minimize request time, we keep Flying Saucer persisted with Nailgun -

https://github.com/martylamb/nailgun

For generating checks, IRS forms and other PDFs that involve precise formatting we use Prawn -

https://github.com/prawnpdf/prawn