6 posts
Arachne's response cache returned 'Brasília' to anyone asking about France — cosine 0.8531 against a 0.85 threshold. The story of a bug born in a CI investigation, the math that hid it, and the entity guard that fixed it without sacrificing recall.
The cover was remade twice, the deployment served the new bytes — and the blog kept showing the old image. The culprit wasn't the build or the CDN: it was a header promising the file would never change for a year. The story of the hunt, the math of immutable caching, and the rule that stuck: reworking an asset requires a new URL.
A wrong Cache-Control header in vercel.json was overriding the revalidate=1800 ISR setting and turning every cache expiry into two synchronous GitHub calls inside the TTFB. The story of how cold cache became warm: 3.6s down to 140ms.
Arachne's vision pipeline evolved: qwen2.5vl:7b on Ollama WSL, arachne-vlm-jobs queue with arachne-vlm-w1 worker, SQLite vlm_cache.db cache (sha256), polling GET /api/extract/image-jobs/{id}. Vision requires JWT, PYTHONPATH api/ and PostgreSQL not SQLite.
Portfolio was 100% functional, 218 tests passing, zero CI errors. But mobile Chrome users saw old versions when restoring tabs. The cause: Chrome's bfcache ignores HTTP headers — and the fix came cross-project from LifeLog.
The simple scraper became a platform. Crawl4AI Sidecar, automatic 4-layer fallback, and SQLite cache with FTS5.