Notes 
secureblue is a security-hardened immutable Linux OS built on Fedora Atomic Desktops. It ships as OCI bootable container images and applies kernel hardening, a hardened memory allocator from GrapheneOS, and a hardened Chromium browser called Trivalent.
Reviewed by Marco Wollank
secureblue
secureblue.dev 4.5 (10)
Rate secureblue: No account needed
Threat level
Hardened
A hardened pick. Worth the effort once you have chosen to shrink your footprint on purpose. Enough for most people. Threat levels
Our take
secureblue pulls the best ideas from GrapheneOS’s hardening work and transplants them to the desktop Linux context: hardened_malloc, proactive kernel parameter lockdown, and an immutable base that cannot be silently modified. It sits on Fedora Atomic, so SELinux and atomic updates come for free. The project is candid that desktop Linux’s security architecture has real structural limits it cannot fully overcome. This is as close as you get on Linux without those caveats. Aimed squarely at users who already want Linux and want the most secure variant of it; not a beginner distro, and some applications work less smoothly under the tighter restrictions.
GitHub at a glance
secureblue/secureblue Apache-2.0
Stars
1,105
+9 this week
Forks
111
18 watching
Last commit
today
healthy
Latest release
v4.9.3
2mo ago, 35 total
Star history
Issues
86% closed
139
open
839
closed
+22 / -21
opened / closed, last 4 weeks
Opened vs closed, last 12 weeks
Commits, last 26 weeks
314 commits, active 26 of 26 weeks
100 contributors since Sep 2023
Languages
- Python 50.2%
- Shell 30.5%
- YAML 7%
- Other 12.3%
Updated daily from the GitHub API. Star tracking since Jun 22, 2026.
Website at a glance
secureblue.dev
A+ score 125
Strong website security headers
Graded by Mozilla HTTP Observatory, tested today
Inspect this site yourself
Measures the security configuration of the tool's own website, not the privacy of the product itself. A strong tool can still score low here.
secureblue alternatives
Fedora Workstation Fedora Workstation: User friendly and easy to setup
Ubuntu Ubuntu: User friendly and easy to setup
macOS Apple's desktop OS. A real privacy step up from Windows, but closed and US-based.
Kicksecure Kicksecure is a security-hardened Debian-based Linux distribution that applies a broad set of kernel and userspace hardening settings out of the box, reducing the attack surface without requiring manual configuration. It also serves as the foundation for the Whonix anonymity OS.
Fedora Atomic Desktops Fedora Atomic Desktops (Silverblue, Kinoite, and others) are immutable Fedora variants where the base OS is read-only and updated atomically via rpm-ostree. Applications run as Flatpaks, and rollback to a prior OS image is built in.
NixOS NixOS is a Linux distribution built entirely on the Nix package manager, where the whole system (kernel, packages, services, and configuration) is declared in a single set of files. Upgrades are atomic and fully reproducible rollbacks are a built-in feature.
secureblue license, in plain English
Apache-2.0 Permissive
Permissive like MIT, with an explicit patent grant and a requirement to flag any changes you make.
Permits
- Commercial use
- Modification
- Distribution
- Patent use
- Private use
Requires
- License and copyright notice
- State changes
Does not provide
- Trademark use
- Liability cover
- Warranty
Why it matters: Permissive licensing lets anyone reuse this, including inside closed products. That is freedom to build on, but no guarantee that downstream copies stay open.
Plain-language summary of the project's license, not legal advice. Read the full text for the exact terms.