Halfway through the series. Instead of a self-congratulating check-in, here's something more useful: a map of the fourteen ideas so far, each in a paragraph, so you can skim the series in five minutes and decide which posts to read properly.

The building side

Day 2: Put rules where they can't be bypassed. In CardBridge, a trigger-enforced state machine in Postgres decides which escrow transitions are legal. The browser can ask for a change; only the database decides. Cost: slower debugging and more ceremony. Gap: no automated tests yet.

Day 3: An optional step must never fail a deploy. A Puppeteer prerender step needed Chrome; Vercel skipped the install; the failure blocked every deploy for about two weeks, and the live site quietly stayed old. Fix: fall back to a serverless Chromium, and if nothing launches, skip and exit 0. Check the live site with curl , don't trust git push .

Day 6: A design system is a list of decisions you refuse to remake.…