Writing

Notes from running an x402 payment stack in production.

• Paying an x402 endpoint from scratch: how far a hand-rolled buyer gets
  2026-09-07 — building a minimal exact-scheme buyer: the duplicate X-PAYMENT header, why network must be CAIP-2, why a valid EIP-3009 signature still fails CDP verification, and what that means if you're selling.
• Why x402scan isn't listing your endpoint
  2026-09-07 — a debugging checklist for v2 endpoints that submitted fine but never appear: L2_NO_PAID_ROUTES, GUIDANCE_MISSING, the bazaar schema header, security: [], origin vs path.
• Migrating an x402 endpoint from v1 to v2
  2026-09-07 — every field that changed between x402 v1 and v2, the base64 PAYMENT-REQUIRED header, and why x402scan rejects a v1 payload outright.
• What npx @tailwindcss/upgrade leaves broken
  2026-09-08 — the codemod does the easy 80%. The 20% it skips — third-party plugins, wholesale theme overrides, renamed utilities in constructed class names, silent currentColor border/ring changes — and a free auditor that finds them.
• The ESLint flat-config migration has no codemod
  2026-09-08 — @eslint/eslintrc's FlatCompat is a compatibility shim, not a migration. The keys you still convert by hand — env, parser strings, the plugins array, overrides, ignorePatterns, parserOptions — and a free auditor that maps them.