Stirling-PDF, the self-hosted PDF workbench, shipped 3.1.0 on October 5, and the release is organized around one graduation. Stirling Sign, the team document signing feature, is out of alpha and enabled by default for new users. It comes with a rebuilt signing interface, and the pitch is the office one: share a document, track it, and collect signatures across an organization without a third-party service holding your paperwork. For a tool that began as a toolbox of one-off conversions, signing is the feature that makes it a system of record, and treating it as default-on is the project saying so.
The rest of the release
The second arrival is experimental: a new embedded conversion tool called Stirling Office Convert, aimed at better conversion results with less memory and more speed than the existing pipeline. It is behind a feature flag, disabled by default, and the notes openly ask users to compare it against the old converter and report back; a native desktop version is mentioned as coming. The text editor keeps expanding in useful directions: tables can now be edited directly in the file, and OCRed image PDFs are editable rather than read-only artifacts. Attachments pick up the expected management actions, add, rename, extract, delete, and the dependency tree gets its usual sweep. The text editor also gains Acrobat-style object editing: delete with backspace, drag to select, resize text boxes and shapes, shift-resize, which is the difference between annotating a PDF and editing one. Performance work lands quietly alongside, with library rescans and thumbnail rewrites no longer firing on every file write, and translation files preloading instead of reloading.
The fixes
The bug list is short and practical: missing translations, account linking for certain versions, auto-rotate on desktop, the teams menu showing for self-hosted installations that have no teams, and the desktop updater occasionally not updating itself. One fix deserves a specific nod because it is a security fix wearing a maintenance costume: a change restricting sensitive endpoints to authenticated human users, which is the kind of tightening that never makes a headline and matters anyway. Two more entries in the same family: signing sessions wait for a signed-in user before fetching anything, and server file listings skip guest accounts entirely.
My read
Signing was the feature that needed to leave the lab for Stirling to compete with the commercial stack, and doing it default-on for new installations is the confident version of shipping it. If you run Stirling for your organization, this is the update where it becomes your PDF workbench rather than a convenient collection of tools. Try the Office converter on documents you know well before enabling it broadly, and walk the new signing flow once before the first person signs something that matters.
Source: the v3.1.0 release.

