Contents
Build logs
Field notes from real builds — specs, adversarial reviews, dead-ends. Every entry ends with a verdict — what worked, what it cost, what blocked.
Browse Features & architectureTutorials & workflowsCase studiesRoadblocks
Analytics Without Cookies, a Banner, or Losing Half the Data to Ad-Blockers How I run PostHog on this site: cookieless, no consent banner, EU-hosted, and reverse-proxied through my own domain so ad-blockers barely touch it. The real Cloudflare Function and client config, both liftable. I Built a Fintech Startup in 2020. What AI Actually Changed In 2020 I launched a fintech stock screener — three years live, 2,000+ users, built by hand. I rebuilt one with AI agents this year. Here's what changed. Can You Use yfinance Commercially? No — Here's the License Research Is yfinance data free to use commercially? No — here's the primary-source license research, done before monetizing was ever on the table, plus the 50-KPI stock screener it protects. My OpenSpec Workflow: Spec-Driven Development With AI Agents The OpenSpec workflow I use with AI agents: spec, adversarial plan review, isolated build, red-team code review, then verify. Real PR numbers inside. Python Writes, TypeScript Reads: One SQLite File, Zero Drift Python for ingestion, TypeScript for the app, one read-only SQLite file as the seam — and one JSON Schema generating matching Zod and Pydantic types.