A lone sailboat on a calm, wide-open sea

The 1M context window, and what it actually costs you 💸

A 1M-token LLM context window is a tool, not a target. How context actually works, why long threads cost more on every turn, and when to start a fresh chat versus keep going, with practical Claude Code tips and /context.

June 10, 2026 · 8 min
Random pipes

STATUS.md: a shared file for multi-agent work

A file-based pattern for coordinating multiple LLM agents on one task: a single shared, per-feature STATUS.md the agents read and write under explicit rules, how to make them follow a protocol and survive context loss, and when not to use it.

May 25, 2026 · 8 min
Homemade and chip optocouplers on a breadboard

How I spent a weekend reinventing a 50-cent chip

What an optocoupler is and how electrical isolation works, built from a discrete LED and phototransistor on a breadboard with measurements, then replaced with a real 4N35 chip, and where optocouplers show up in actual circuits.

April 25, 2026 · 6 min
Lilka ESP32 device used as a Kobo page-turner remote

DIY Bluetooth Kobo page-turner remote with ESP32 and Lilka

Building a DIY Bluetooth page-turner remote for a Kobo e-reader by making an ESP32-S3 Lilka device act as a BLE HID keyboard, including BLE debugging on Debian, testing on the Kobo Clara 2E, and the full project code.

January 23, 2026 · 6 min
A minimal LLM Ops stack with tracing and model costs

A minimal LLM Ops stack with tracing and model costs

Building a minimal LLM Ops stack: a FastAPI “customer support reply drafter” instrumented with Langfuse for request tracing, grounded retrieval, and per-request model cost tracking, so every LLM call is inspectable.

January 14, 2026 · 11 min

RAG: A (mostly) no-buzzword explanation

Retrieval-Augmented Generation (RAG) explained without buzzwords: how it gives an LLM the right data at answer time to fix stale knowledge and hallucinations, the step-by-step flow, its benefits over fine-tuning, and when RAG is not the answer.

November 19, 2025 · 4 min

Unikernels, without the marketing

Unikernels without the hype: an app compiled with only the OS it needs into a tiny microVM (Firecracker/KVM) for millisecond cold starts and strong isolation, the trade-offs versus VMs and containers, when to use or skip them, and how Unikraft powers Prisma Postgres.

October 15, 2025 · 5 min
Solving the Openfire Lab Blue team challenge

Solving the Openfire Lab Blue team challenge

A blue-team walkthrough of the CyberDefenders Openfire challenge using Wireshark and Zui: recovering the CSRF token and credentials, tracing the malicious plugin upload and reverse shell, and identifying the exploited CVE.

August 24, 2025 · 4 min
Solving the ShadowCitadel Lab Blue team challenge

Solving the ShadowCitadel Lab Blue team challenge 🫆

A host-based forensics walkthrough of the ShadowCitadel challenge: following the attack from a malicious email attachment through a PowerShell downloader and second-stage executable to the C2 beacon IP and persistence mechanisms.

August 10, 2025 · 16 min

How to prevent token misuse in LLM integrations

Preventing prompt injection and token abuse in LLM integrations: a Chrome-extension example attack, then defenses including input validation, narrow prompts, output filters, token limits, rate limiting, and LangChain for pre/post-processing and usage tracking.

July 22, 2025 · 6 min