The latest articles on DEV Community by loki_lancer (@loki_lancer). https://dev.to/loki_lancer https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.us-east-2.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F4175155%2F7553b29f-70fc-429f-910c-4f375943ded9.png https://dev.to/loki_lancer en loki_lancer Sat, 10 Oct 2026 11:27:14 +0000 https://dev.to/loki_lancer/laptop-lab-zero-install-browser-hardware-diagnostics-2amb https://dev.to/loki_lancer/laptop-lab-zero-install-browser-hardware-diagnostics-2amb <p>I built Laptop Lab — a single-page web app that tests your laptop's display, camera, mic, keyboard, touchpad, speakers and battery. No install, no dependencies, no data leaves your machine.</p> <h2> What it does </h2> <ul> <li>Display: full-screen color fills for dead pixels</li> <li>Camera: live preview with real resolution and frame rate</li> <li>Microphone: level meter with peak hold</li> <li>Keyboard: on-screen layout, tracks rollover</li> <li>Touchpad &amp; mouse: clicks, scroll, pinch, events/sec</li> <li>Speakers: per-channel tones, 100 Hz–10 kHz sweep</li> <li>Battery: charge level and state (Chromium only)</li> </ul> <h2> Technical notes </h2> <ul> <li>Pure vanilla HTML/CSS/JS. No build step, no frameworks.</li> <li>AudioContext fallback chain for Safari (StereoPannerNode → ChannelMergerNode → mono)</li> <li>Battery API feature-detected with graceful message</li> <li>getUserMedia requires HTTPS — app detects and explains</li> <li>Stamp system uses localStorage with per-test thresholds</li> </ul> <h2> Links </h2> <ul> <li>Live: <a href="https://lokilancer.github.io/Laptop-Lab/" rel="noopener noreferrer">https://lokilancer.github.io/Laptop-Lab/</a> </li> <li>Code: <a href="https://github.com/lokilancer/Laptop-Lab" rel="noopener noreferrer">https://github.com/lokilancer/Laptop-Lab</a> <img src="https://media2.dev.to/dynamic/image/width=800%2Cheight=%2Cfit=scale-down%2Cgravity=auto%2Cformat=auto/https%3A%2F%2Fdev-to-uploads.s3.us-east-2.amazonaws.com%2Fuploads%2Farticles%2Fjpwgixghu5kqm9yl0xa9.png" alt=" " width="800" height="566"> </li> </ul> javascript webdev opensource