Best Free and Open Source Software

posted by Rianne Schestowitz on Oct 25, 2026

• FusionPBX - multi-tenant VoIP PBX management platform

  The software is suitable for anything from a small business telephone system to a multi-tenant deployment serving different organisations. Its domain-based architecture allows administrators to manage separate telephone environments from a single installation, with each domain maintaining its own users and configuration.

  FusionPBX combines everyday PBX administration with more advanced call-handling capabilities. It uses a modular application structure, allowing administrators to configure the features required for their deployment.

  This is free and open source software.

• LibreFolio - self-hosted financial portfolio tracker

  The software supports several asset classes, including shares, exchange-traded funds, bonds and cryptocurrencies. It is particularly useful for investors with accounts at different brokers, as transactions can be imported and combined into one portfolio.

  LibreFolio places considerable emphasis on transparency in its financial calculations. Rather than treating performance figures as unexplained results, it uses documented calculation methods for investment returns and acquisition costs.

  This is free and open source software.

• 11 Best Free and Open Source Linux System Log and systemd Journal Viewers

  Many Linux distributions use systemd, a system and service manager that includes a centralised logging facility called the systemd journal. Managed by systemd-journald, it collects messages from the kernel, system services, applications and other sources. Unlike traditional plain-text log files, the journal stores structured entries containing metadata such as timestamps, severity levels and service identifiers.

  System log and journal viewers make this information easier to interpret. They provide ways to browse, search, filter and monitor events, isolate errors, examine individual services and identify patterns that might otherwise be overlooked. Some offer graphical interfaces, while others provide powerful terminal-based navigation and filtering.

  These tools are useful for system administrators diagnosing server problems, developers debugging applications, and desktop users troubleshooting hardware, services or unexpected system behaviour.

  Here’s our verdict captured in a legendary LinuxLinks-style ratings chart. Only free and open source software is eligible for inclusion here.

• Transition - graphical multimedia to audio converter

  Transition is a graphical application for converting audio and video files into audio formats on Linux. It is designed for people who want to prepare recordings, music or extracted soundtracks without building FFmpeg commands or working through the controls of a full audio editor.

  The workflow is centred on selecting a collection of source files, choosing the desired output settings and starting conversion. Different kinds of multimedia can be included in a job, so an audio-only source and a video containing a soundtrack can be processed from the same interface. It is equally suited to occasional single-file conversions and larger queues. Its adaptive design also accommodates narrower screens while keeping the conversion controls accessible.

  This is free and open source software.

• liber - local-first reference manager for academic research

  The software stores each paper in its own directory, containing a BibTeX record and optionally a PDF document and Markdown notes. Rather than storing everything in an opaque database, liber uses ordinary files that can be inspected, backed up and managed with other tools.

  A central index tracks bibliographic metadata, making it possible to locate papers and maintain an organised collection as a research project grows. The command-line interface is suitable for scripting and terminal-based workflows, while the web interface provides a graphical alternative for managing references and associated documents.

  This is free and open source software.

• PKScreener - stock screening and technical analysis tool

  The application provides an extensive collection of predefined scanners, together with configurable screening options for investigating individual stocks, market indices and watchlists. Traders can combine different conditions to narrow down potential opportunities instead of examining large numbers of charts manually.

  PKScreener operates through an interactive command-line interface on Linux and can also run inside a Docker container. Python package installation and platform-specific executable downloads are available. Its emphasis is on technical analysis and identifying candidates for further research rather than managing long-term investment portfolios.

  This is free and open source software.

• grimshot - command-line screenshots for Sway

  Different targets can be specified without changing the basic workflow. Users can capture the focused window, the active output or all displays, while interactive modes allow a window or rectangular area to be selected with the mouse.

  Captures can be written to a PNG file, sent straight to the Wayland clipboard, or saved and copied together. Optional notifications and delayed captures provide additional control without requiring a persistent background service.

  This is free and open source software.

• KDE Journald Browser - graphical systemd journal viewer

  Systemd journals contain messages generated by the kernel, background services and applications. These records are valuable when diagnosing failed services, unexpected shutdowns, hardware problems and other system issues.

  KDE Journald Browser can examine journals from the local machine as well as saved databases collected from other Linux systems. This also makes it useful for investigating problems after an affected system has been shut down or is no longer accessible.

  This is free and open source software.

• CalibRaw - GPU-accelerated RAW photo editor

  The application uses a Rust-based processing engine with GPU compute shaders. It supports numerous camera RAW formats through LibRaw and Rawler, alongside conventional image formats including JPEG, PNG, HEIC and TIFF. Adjustments are saved in sidecar files, allowing photographs to be revisited and edited without altering the originals.

  CalibRaw combines traditional photographic adjustments with local AI-powered masking, noise reduction and object removal. It also offers HDR merging, focus stacking, creative effects and tools for organising photo collections. AI processing takes place locally, with models downloaded only after user consent.

  This is free and open source software.

• Autohook - lightweight Git hook manager

  The application uses symbolic links to connect Git’s hook entry points to a common script. When an event occurs, Autohook locates the corresponding directory and executes the scripts stored there.

  Autohook supports two approaches to managing hooks. Scripts can be stored directly in a repository, allowing them to be shared with the source code and vary between branches. Alternatively, they can be maintained centrally for use across multiple projects and development environments.

  This is free and open source software.