Tech Deep Dive
Source-code-level analysis and system design explorations. Covers databases, search engines, distributed systems, and architecture internals.
8 articles
The Mysterious 400 in Claude Multi-Turn Chats: Debugging a Thinking Signature Corruption
A customer's Claude extended-thinking conversations kept failing with 400 Invalid signature — but only on some gateway channels. A full postmortem: what the signature mechanism is, how a proxy's JSON re-serialization silently corrupts base64, five controlled experiments that pinned it down, and a fix checklist for every LLM gateway developer.
Subtitle Position Detection with OpenCV and Amazon Nova
A hybrid CV + LLM pipeline for automatic subtitle detection — 6 iterations to reach 83% accuracy on multilingual video.
Claude Code vs OpenClaw: 510K vs 530K Lines Source Code Showdown
After Claude Code's source leak exposed 512K lines of TypeScript, we finally get a true apples-to-apples comparison with OpenClaw — architecture, agent definitions, security, and design philosophy.
How AI Coding Agents Actually Work: A Source Code Deep Dive
We traced the source code of Amazon Q CLI and Claude Code to understand how AI coding agents really work under the hood.
OpenClaw vs Claude Code: Architecture and Strategy Compared
Two AI agent products, two radically different philosophies. A deep comparison of architecture, adoption, and what's next.
How to Design a Full-Site Search Engine with Elasticsearch
Multi-source indexing, CDC sync, permission-aware search, hot keywords, and typeahead — a complete Elasticsearch architecture guide.
Building a Knowledge Base Search Engine with FSCrawler and Elasticsearch
Index PDFs, Word docs, and scanned files into Elasticsearch with FSCrawler. Covers OCR, custom mappings, and production setup.
Adding a Unique Index to a 15-Million-Row MySQL Table: A Production War Story
We added a unique index to a 15M-row live table and caused an outage. Here's what went wrong and the right way to do it.