Blog
Notes from a shipping startup
Operations, engineering, and the occasional rant about carrier APIs.
Operations
· 6 min readWhy the wallet model changes everything for SaaS billing
Most shipping platforms invoice you monthly for labels you bought. We invert that — pre-fund a wallet, and every label deducts atomically. Here’s why.
Read moreEngineering
· 9 min readHow we built atomic label purchases
A deep dive into the SQL function that guarantees you’re never charged for a label that didn’t print.
Read moreShipping
· 5 min readThe 7 weirdest Shopify CSV export quirks (and how we handle them)
Shopify’s order export changes silently. Our column-aliases library handles all of them — here’s the catalog.
Read moreShipping
· 8 min readChoosing the right carrier by destination zone
USPS dominates zones 1–4 for under 1lb. UPS wins zones 5+. FedEx beats both for residential 2-day. The data, by zone.
Read moreEngineering
· 11 min readHow we use Postgres RLS for true multi-tenant isolation
Every table, every query, every test. The pattern, the helper functions, and the audit script we run before every deploy.
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