Thang Viet To — Writing https://thangto.vanilla-ott.com/blog 9+ years on systems where mistakes cost money: exactly-once event pipelines, multi-tenant commerce SaaS, and a 300,000-product headless storefront. Node.js, TypeScript, PostgreSQL, Redis, AWS. en Debugging a headless Shopify checkout you don't own https://thangto.vanilla-ott.com/blog/debugging-headless-shopify-checkout https://thangto.vanilla-ott.com/blog/debugging-headless-shopify-checkout When a headless checkout hand-off fails, the failing surface belongs to Shopify. Here's how to tell your bug apart from platform behaviour. Thu, 14 May 2026 00:00:00 GMT The Storefront API at 300,000 products https://thangto.vanilla-ott.com/blog/shopify-storefront-api-at-300k-products https://thangto.vanilla-ott.com/blog/shopify-storefront-api-at-300k-products Cursor pagination is fine at 500 products and painful at 300,000. What changes when your catalogue outgrows the happy path. Mon, 02 Mar 2026 00:00:00 GMT Idempotency isn't a safeguard, it's the design https://thangto.vanilla-ott.com/blog/idempotency-is-the-design https://thangto.vanilla-ott.com/blog/idempotency-is-the-design Every webhook arrives twice eventually. On money paths, that's not an edge case to handle later — it's the shape of the system. Tue, 20 Jan 2026 00:00:00 GMT