Best Free and Open Source Software

posted by Rianne Schestowitz on Sep 24, 2026

• Best Free and Open Source Alternatives to Google Cloud Build

  Google Cloud Build is a managed build service running on Google Cloud infrastructure. It can pull source code from repositories or cloud storage, execute a series of build steps, and produce artifacts such as container images and Java archives.

  Build steps run in containers. You can use builders supplied by Google and the community, or create your own. Builds can also be triggered automatically when code changes, making Cloud Build useful for continuous integration and delivery.

  Google Cloud Build is proprietary software. Here are our recommended free and open source alternatives.

• Journal Viewer - graphical systemd journal viewer

  It provides a graphical alternative to working directly with journalctl. The application displays a summary graph of recent log activity and provides a quick search facility for filtering messages using case-insensitive text matching.

  More advanced filtering lets you narrow entries by log priority, date range, systemd service unit, transport and system boot. Individual log entries can be expanded to reveal more information, while infinite scrolling makes it convenient to browse large quantities of journal data.

  This is free and open source software.

• ScoutFS - clustered file system for large archival systems

  It takes a different approach from putting an archive application on top of a conventional file system and repeatedly walking an enormous namespace. ScoutFS provides archive-oriented metadata and interfaces that let archive agents find and maintain files more directly. Multiple hosts can mount the same file system while sharing access to its underlying block devices, allowing a deployment to add nodes as archival bandwidth requirements increase.

  Its design is aimed at installations where both file population and storage throughput can become extreme, while applications still see familiar file-system semantics. ScoutFS is therefore a specialist option for large data repositories and active archives rather than a general-purpose desktop file system.

  This is free and open source software.

• knife - reverse engineering toolkit for binary analysis

  The program combines a command-line interface with an interactive terminal workspace. The latter provides a more exploratory workflow, letting analysts move between recovered functions, listings, cross-references and other views while retaining their own annotations. The underlying analysis engine is shared between the interfaces, so information recorded during an investigation remains available when switching between commands and the interactive environment.

  This is free and open source software.

• sbomnix - generate Software Bills of Materials for Nix

  It accepts Nix flake references, derivations and store paths, determines their dependencies and exports the resulting inventory in standard SBOM formats. The distinction between build-time and runtime dependencies is important in Nix, and sbomnix can work with either. When sufficient Nixpkgs information is available, it also enriches discovered components with metadata rather than limiting the result to package names and dependency relationships. The repository contains several related utilities for investigating Nix software supply chains.

  This is free and open source software.

• Neko - self-hosted virtual browser and remote desktop

  Neko is a self-hosted virtual browser and remote desktop system that streams a Linux graphical environment through WebRTC.

  Instead of transferring browser state or individual application data to participants, Neko runs the graphical session remotely and delivers synchronized audio and video to connected users. Multiple participants can enter the same environment and interact with it, making the software useful for collaborative browsing, demonstrations, teaching, watch parties, support sessions and controlled remote access to applications.

  This is free and open source software.

• RTAB-Map - graph-based SLAM and 3D mapping application

  It is designed to work with visual and range sensors and uses incremental appearance-based loop closure detection to recognise when a robot revisits a previously mapped location. Accepted loop closures add constraints to the map graph, which can then be optimised to reduce accumulated positioning error. A memory-management strategy limits the number of locations considered during loop detection and graph optimisation, helping the system remain practical for large environments. RTAB-Map can be used as a standalone graphical application or integrated into a wider robotics stack, with data stored in project databases that can be inspected, replayed and processed by accompanying tools.

  This is free and open source software.

• Molsketch - 2D molecular structure editor

  Molsketch supports more than straightforward atom and bond diagrams. Drawings can contain reaction arrows, equilibrium arrows, mechanism arrows, frames, brackets and free text. It can also represent lone pairs and radical electrons. Alignment, spacing and structure-cleanup tools help produce consistent diagrams, and users can explicitly control the direction of attached hydrogen atoms where needed.

  The program uses its own MSK document format and MSM format for individual molecules. OpenBabel integration significantly extends file handling by allowing structures to be imported from and exported to additional chemistry formats. Molsketch can also use OpenBabel to optimize coordinates. Recent development has included fixes to its OpenBabel export path as well as continued work on rendering and drawing behaviour.

  This is free and open source software.

• JFFS2 - log-structured file system for raw flash storage

  It sits directly on Linux Memory Technology Device (MTD) flash rather than relying on a translation layer that makes flash behave like an ordinary disk. Raw flash has very different constraints: erase operations happen at block granularity, blocks have finite erase lifetimes, and NAND devices restrict repeated writes to a page.

  JFFS2 is integrated into the Linux kernel and is suited to relatively modest NOR and NAND flash devices. It does not maintain an on-media index, so mounting requires a scan of the medium and memory consumption grows as the file system becomes larger. This makes it less scalable than UBIFS for large flash devices, but it remains useful in embedded systems.

  This is free and open source software.

• OpenPonk - metamodeling platform and modeling workbench

  Rather than concentrating on a single modeling notation, OpenPonk provides a common platform that can be extended through plugins. This allows different modeling languages and techniques to share the same underlying workbench while retaining tools tailored to their particular notation. The platform is designed to support activities extending beyond diagram creation, including execution, simulation and source code generation.

  OpenPonk is a desktop application and runs on Linux as well as other major desktop platforms.

  This is free and open source software.