Shadowfetch Linux 3.0 sandboxes AI coding agents with rollback
Autonomous coding agents are powerful and unpredictable in equal measure. Shadowfetch Linux 3.0, codenamed Umbra, is a Debian Testing-based distro built around KDE Plasma 6 that now ships a dedicated system for keeping those agents from doing things you didn’t intend.
The Fireline System
The centerpiece of 3.0 is Fireline, which combines two components. The first, shadowfetch-firebreak, launches coding agents including Claude Code, Codex CLI, Cursor, and Aider inside a Bubblewrap sandbox. Inside that environment, the OS is mounted read-only, write access is restricted to the selected project under ~/Workspaces, network access can be disabled, and API keys or auth tokens are stripped from environment variables before the agent starts.
The second component, shadowfetch-checkpoint, takes workspace snapshots before and after each agent session. On Btrfs systems it uses subvolume snapshots; other filesystems fall back to portable archives. You get a content-based diff of what changed and can restore the workspace to its prior state if needed.
️ Four MCP Servers Included
Shadowfetch 3.0 also ships four first-party Model Context Protocol servers:
- A read-only passport service exposing privacy-scrubbed system information
- A Phoenix service for viewing available restore points
- A checkpoint service for creating and managing workspace snapshots
- A filesystem service scoped to a restricted access area
The distro provides a command for generating MCP configuration that can be copied directly into compatible AI clients.
Local Model Recommendations
A new tool called shadowfetch-ai-ignition checks available VRAM and recommends models that fit the hardware rather than dumping a generic list. Its catalog currently includes openly available models like Qwen3, Devstral, and gpt-oss. The distro bundles no models, and all downloads are explicitly user-initiated.
Everything Else Still Works
Prior Shadowfetch features remain: the Shadowfetch Guide and private System Passport, Phoenix Btrfs restore points, the Fireproof update system that simulates package changes before applying them, and the optional Buzz local-AI workspace. The distro still uses Calamares for installation, supports BIOS and UEFI, offers LUKS2 encryption, ships a signed ISO and signed APT repository, and contains no telemetry. It runs on 64-bit x86 only.
I’m founder of BizStack at Cagri Sarigoz LLC and a passionate advocate for entrepreneurs.
With over 14 years in tech, marketing, and AI, including my role as Head of SEO at CitizenShipper and co-founder of TaleBot at Intale AI, I’m dedicated to sharing genuine, useful product insights and tips.
At BizStack, I aim to cut through the digital noise to provide clear, actionable advice.
And more than all else, I’m a father to a (always) little girl and a husband.
Contact me at [email protected] for assistance.
