https://ivan2kh.com/ Notes on AI, infrastructure, and software engineering https://ivan2kh.com/posts/jaredfromsubway-honeypot/ Fri, 26 Jun 2026 00:00:00 +0000 On-chain post-mortem of the 2026-06-20 counter-MEV honeypot that drained the jaredfromsubway.eth sandwich bot of ~$7.5M: root cause, the block-armed mint/consume switch, the transferFrom sweep, and hardening notes. https://ivan2kh.com/posts/grammar-quest-internals/ Mon, 20 Apr 2026 00:00:00 +0000 Visual-first tour of the Grammar Quest backend — pipeline timeline, data-shape diagrams, sprite cache decision path, eval harness flow, judge dimensions, CEFR matrix. https://ivan2kh.com/posts/grammar-quest/ Tue, 31 Mar 2026 00:00:00 +0000 Building an AI engine where your grammar errors mutate the game world in real time — and the architecture is stranger than you'd expect. https://ivan2kh.com/posts/claude-token-cost-anatomy/ Wed, 18 Mar 2026 00:00:00 +0000 Real data from 315 Claude Code sessions reveals how context size, caching, and tool-use chains shape API costs. Interactive chart with 20K+ data points.