The two leading open-source document management projects, compared on the signals that predict whether a dependency survives: commit cadence, release history, licence and health.
Stirling-PDF is the safer default: actively maintained maintenance, 1627 commits in the last twelve months and a health score of 100/100, against 1429 commits and 100/100 for Paperless-ngx. Licence still decides the commercial question — Stirling-PDF ships under Apache-2.0, Paperless-ngx under GPL-3.0. Both are Document Management projects; the category scores 72/100 on saturation with 41 open-source implementations tracked.
| Metric | Stirling-PDF | Paperless-ngx |
|---|---|---|
| GitHub stars | 90k | 44k |
| Maintenance status | Actively maintained | Actively maintained |
| Commits (12 months) | 1627 | 1429 |
| Commits (3 months) | 631 | 363 |
| Active months / 12 | 12 | 12 |
| Last commit | 2026-08-14 | 2026-08-15 |
| Last release | 2026-08-06 | 2026-08-01 |
| Licence | Apache-2.0 | GPL-3.0 |
| Licence family | permissive | copyleft |
| Health score | 100/100 | 100/100 |
| Replaces | — | — |
| Repository | stirling-tools/stirling-pdf | paperless-ngx/paperless-ngx |
Repository metadata refreshed August 2026. Stars never decay — read the maintenance rows first.
Local hosted web application that allows you to perform various operations on PDF files, such as merging, splitting, file conversions and OCR.
Scan, index, and archive all of your paper documents with an improved interface (fork of Paperless).
On maintenance signals, Stirling-PDF leads: 1627 commits in the last twelve months across 12 active months, versus 1429 commits and 12 active months for Paperless-ngx. Star counts (90k vs 44k) reflect historical popularity, not current health, so read them second.
Stirling-PDF is licensed under Apache-2.0 (permissive) and Paperless-ngx under GPL-3.0 (copyleft). Permissive licences (MIT, Apache, BSD) allow closed commercial products. Copyleft (GPL) triggers on distribution and AGPL triggers on network use, which covers SaaS. Source-available licences usually forbid competing hosted services outright.
Paperless-ngx is marked actively maintained with its last commit recorded 2026-08-15 and 363 commits in the last three months. It still qualifies as having momentum, so it is a viable dependency.
The Document Management category is rated crowded at 72/100, with 22 maintained implementations. In a crowded category every prospect can find a free version in minutes, so your wedge has to be something maintainers structurally will not build: compliance, SLAs, managed scale or a workflow they reject.
Communication
Software Development
Miscellaneous
Media Streaming
File Transfer
Content Management Systems (CMS)
Money, Budgeting & Management
Games
Two maintained free tools already own this category. IdeaProof scores your idea against live competitors, market size and 1,000+ documented failures in about two minutes.
Validate your idea freeSearch this database by category and by the commercial product you would replace. It covers 1665 projects across 130 categories, each mapped to the paid tool it substitutes. If your category shows a "Crowded" verdict, a maintained free version almost certainly exists and your positioning has to account for it.
No. It means free is your price anchor. Plenty of large companies were built next to a good open-source project — the ones that failed were the ones selling the same job at a price the free tool made indefensible. Find the part of the job the project deliberately does not do, and sell that.
Each category gets a 0–100 score built from three inputs: how many implementations exist, what share of them are still actively maintained, and how far ahead the leading project is compared with the category median. 62+ is Crowded, 38–61 Contested, under 38 Open. 11 categories are Crowded and 88 are Open.