The latest articles on DEV Community by Rick Blundell (@binrick). https://dev.to/binrick https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F3959206%2Fdecccc6e-d2d3-4923-8a95-055095b40b77.jpeg https://dev.to/binrick en Rick Blundell Fri, 29 May 2026 23:00:20 +0000 https://dev.to/binrick/show-dev-tmpfstech-720-hands-on-linux-challenges-on-real-ephemeral-vms-in-your-browser-23kf https://dev.to/binrick/show-dev-tmpfstech-720-hands-on-linux-challenges-on-real-ephemeral-vms-in-your-browser-23kf <p>Every Linux tutorial I've ever read tells you <em>about</em> a command. None of them<br> hand you a real, broken box and say "fix it." So I built one that does:<br> <strong><a href="https://tmpfs.tech" rel="noopener noreferrer">tmpfs.tech</a></strong> — hands-on Linux &amp; open-source challenges<br> that run on a live, throwaway VM you actually control, right in your browser.</p> <h2> How it works </h2> <ul> <li>Pick a challenge → you get a real Linux session in an <strong>in-browser terminal</strong>.</li> <li>The task is a genuine scenario, not a quiz: repair broken nginx, write an nftables ruleset, debug a failing systemd unit, fix a storage mount, eradicate cron-based persistence after a breach.</li> <li>The VM is <strong>ephemeral</strong> — spun up just for you, torn down when you finish. Nothing touches your own machine.</li> <li>Your work is <strong>graded automatically</strong> against the actual system state, so a pass means you really fixed it.</li> </ul> <h2> What's in it </h2> <p>720 challenges across 16 tracks — General Linux, Networking, Firewall, systemd,<br> Security &amp; TLS, Web &amp; Deploy, Bash &amp; Scripting, Text Processing, Storage &amp; Disk,<br> Kubernetes — plus two wargame tracks:</p> <ul> <li> <strong>Offensive Lab</strong> — local privilege-escalation CTF (capture a root-only flag via SUID/sudo/passwd misconfigs).</li> <li> <strong>Defense &amp; IR</strong> — evict rogue UID-0 accounts, kill systemd/cron persistence, and attribute a breach straight from <code>auth.log</code>.</li> </ul> <h2> A few things I'm proud of </h2> <ul> <li> <strong>Zero signup to start.</strong> Guest play works the moment you land.</li> <li> <strong>Truly isolated.</strong> Each session is its own VM, auto-reaped on idle so nothing runs away.</li> <li> <strong>A skill ladder, not a syllabus.</strong> A Glicko-2 rating tracks your level and recommends the next challenge by difficulty gap — closer to a puzzle feed than a fixed course.</li> </ul> <p>I'd genuinely love feedback on the challenge design — which tracks feel right,<br> what's missing, and what you'd want to learn-by-breaking next.</p> <p>Try it here: <strong><a href="https://tmpfs.tech" rel="noopener noreferrer">https://tmpfs.tech</a></strong></p> linux devops showdev opensource Rick Blundell Fri, 29 May 2026 22:54:35 +0000 https://dev.to/binrick/-2g3m https://dev.to/binrick/-2g3m