$ whoami
Yonga Springfield
aka halfabit.
Security researcher. I break things to understand them — then write down what it taught me.
$ ls ./latest --sort=date ALL_POSTS
01 Vuln Bank Part 1: Tech Stack & Architecture The stack behind the vuln bank — Effect, Hono, Postgres — and the one idea that shapes everything: the RAG system and the MCP interface are two separable pieces that only happen to ship together. 02 Building a Vuln Bank for My Hackbot Kicking off a series on giving an autonomous bug-hunting agent a long-term memory — a curated vulnerability knowledge base served over MCP, and the tradeoffs behind it. 03 CVE-2026-31419: Heap Overflow in an MQTT Broker A malformed CONNECT packet, a 40-byte overwrite, and a weekend of heap grooming.