Practical guides on Linux, AI, self-hosting, and developer tools

How to Build a Real-Time Chat with WebSockets and Vanilla JavaScript

A WebSocket-based real-time chat needs two pieces: a server that holds persistent connections and broadcasts messages between clients, and a browser client that opens a WebSocket connection, sends messages on form submit, and renders incoming messages in the DOM. Using Node.js with the ws library and vanilla JavaScript on the client - no React, no Socket.IO, no build step - the complete implementation is under 150 lines of code and handles dozens of simultaneous connections on commodity hardware. This tutorial walks through the entire build.

How to Build a Whole-Home Audio System with Snapcast and Home Assistant

Yes, you can build a synchronized multi-room audio system that rivals Sonos for under $300 total - covering five rooms. Snapcast is an open-source server-client audio player that streams music to every room in your house with sub-millisecond synchronization, and Home Assistant turns the whole thing into a controllable smart home system with per-room volume, source switching, and automation. The total cost per room runs between $30 and $50 depending on your speaker choice, synchronization stays within 1ms across rooms (humans can’t detect delays under 5ms), and the entire system runs locally on your network with zero cloud dependency or monthly subscriptions.

Local AI Image Upscaling: Real-ESRGAN vs. Topaz vs. SUPIR

For local AI image upscaling in 2026, Real-ESRGAN is the best free option with strong speed and solid quality for general upscaling. Topaz Photo AI delivers the highest overall quality with intelligent noise reduction and face recovery, but costs $199/year. SUPIR (Scaling Up to Excellence) produces the most detailed and photorealistic results on heavily degraded images, but demands 12+ GB VRAM and runs 10-50x slower than the alternatives. The right choice depends entirely on your workload: Real-ESRGAN for batch processing and automation pipelines, Topaz for professional photography workflows, and SUPIR for maximum quality on individual hero images where time is not a factor.

The State of Consumer SBCs in 2026: Trends, Trials, and the RISC-V Frontier

The consumer SBC market in 2026 is not dead - it is just no longer what it was sold as. Raspberry Pi, Orange Pi, Rock Pi, and the rest of the single-board computer crowd now ship 70-80% of their units to industrial customers: factory automation, digital signage, point-of-sale terminals, and medical devices. The $35 computer that was supposed to put a hackable Linux machine in every teenager’s bedroom is now more likely to be bolted inside a vending machine in a shopping mall.

Upgrade Your 3D Printer with Klipper: A Complete Setup Guide

Klipper is a 3D printer firmware that offloads motion planning calculations from the printer’s microcontroller to a Raspberry Pi or similar single-board computer. The result is faster print speeds (300-500mm/s on a tuned Voron), pressure advance for cleaner corners, input shaping to kill ringing artifacts, and real-time configuration changes with no re-flashing. As of 2026, Klipper paired with a Mainsail or Fluidd web UI running on a Raspberry Pi 5 or Orange Pi 5 Plus is the default stack for anyone serious about 3D printing.

Gemma 4 Architecture Explained: Per-Layer Embeddings, Shared KV Cache, and Dual RoPE

Gemma 4 , released on April 2, 2026, ships four model variants under the Apache 2.0 license. The 31B dense model ranks third on the Arena AI text leaderboard with a score of 1452. The 26B MoE model scores 1441 while activating only 3.8B of its 26B total parameters per forward pass. These numbers raise the obvious question: what architectural decisions make this possible? Three specific design choices - Per-Layer Embeddings (PLE), Shared KV Cache, and Dual RoPE - break from the standard transformer recipe in ways that have real consequences for inference cost, memory footprint, and fine-tuning strategy. The rest of this post covers those mechanisms, the Mixture-of-Experts layer, and the multimodal encoders.

How to Build a Portable Solar-Powered Raspberry Pi Server

Yes, you can build a self-sufficient, portable Raspberry Pi server powered entirely by the sun - no mains power, no generator, no ongoing fuel cost. With a 30W solar panel, a 12.8V LiFePO4 battery, a charge controller, and a handful of systemd scripts, you can run a weather station, a mesh network node, or a local web server indefinitely from a fence post, a rooftop, or a field station. This guide walks through the math, the parts, and the software that make it work reliably rather than just technically possible.

How to Build Smart Garden Irrigation with Home Assistant and a Rain Sensor

A smart garden irrigation system built on Home Assistant combines a Wi-Fi-enabled sprinkler controller (commercial or DIY), a rain sensor (physical or API-based), and automations that cancel or adjust watering schedules based on recent rainfall, soil moisture, and the weekly forecast. With the WiseWater integration and Home Assistant 2025.12’s native irrigation scheduling dashboard, this setup is now a genuinely practical alternative to expensive standalone smart irrigation systems that depend on cloud services. Here is how to build one from scratch.