Top pick
Community-governed GNU/Linux with huge package archives and conservative stability.
linuxserverstablecommunity
Editorial catalog
Open Source Catalog of Apps and Tools - curated with love and care
OpenCatalog is curated by FLOSSK. It highlights genuinely open, actively maintained tools with clear documentation and real-world adoption. Search, filter, compare, and read why each entry belongs here—not an exhaustive directory.
Top picks
Strong defaults in their categories—balanced quality, maintenance, and usefulness.
Top pick
Up-to-date RPM distribution with strong developer defaults and QA culture.
linuxdesktopdeveloperrpm
Top pick
Widely adopted Debian-derived OS with long-term support and huge documentation reach.
linuxltscloudbeginner-friendly
Top pick
Debian-based distribution maintained by Offensive Security, shipping thousands of pre-packaged security and penetration-testing tools.
linuxsecuritypentestdebian-basedassessment
Top pick
Independent browser engine with strong privacy tooling and extension APIs.
browserprivacygeckocross-platform
Top pick
Firefox-based browser configured for Tor network privacy and anti-fingerprinting defaults.
privacytorsecurity
Top pick
Full office suite with strong ODF support and broad import/export filters.
officeodfoffline
Office suite emphasizing Microsoft Office compatibility and ribbon UX.
officeooxmlbusiness
Top pick
Markdown-centric notes with optional E2EE sync and broad cross-platform clients.
notesmarkdownpkme2ee
Browse by category
Practical groupings from operating systems and browsers to databases, monitoring, and education—each with multiple vetted entries where the ecosystem supports it.
50 tools
Operating Systems
Linux distributions and BSD systems for desktop, server, and specialized roles.
20 tools
Web Browsers
User agents for the open web with strong privacy and standards alignment.
15 tools
Office & Productivity
Documents, spreadsheets, and presentations without proprietary lock-in.
49 tools
Notes & Knowledge
Markdown notes, PKM, and self-hosted knowledge bases.
19 tools
Communication & Collaboration
Chat, federated messaging, and team collaboration platforms.
7 tools
Desktop and mobile clients for open standards (IMAP/JMAP).
18 tools
File Sync & Storage
Peer sync, self-hosted clouds, and object storage APIs.
18 tools
Media Players
Playback engines for local and streaming media with broad codec support.
95 tools
Developer Tools
Languages, compilers, Git, and everyday engineering utilities.
Frequently asked questions
How the catalog works, how entries are selected, and how to use the editorial comparisons responsibly.
What is OpenCatalog?
OpenCatalog is an editorial catalog of free and open source software (FOSS), co-authored by FLOSSK, @samikciku, and AI. It highlights actively maintained tools with clear documentation and practical adoption—not a complete directory of every OSS project.
How are tools selected for the catalog?
Entries are curated using editorial criteria: open license, evidence of maintenance, documentation quality, and real-world usefulness. Each listing explains why the tool is included, with strengths and limitations.
Can I compare open source tools on the site?
Yes. Use Compare from browse or tool pages to see license, maturity, platforms, and editorial fields side by side on https://catalog.flossk.org/compare.