Senior PHP Programmer
Tungthanasin Co., Ltd. (Easy Money)
- POS platform — core maintainer: the custom-MVC PHP point-of-sale and inventory system behind a 90+ branch retail network — 20 controllers, 31 models, 151 views, 418 routable actions. Roughly 3,500 of the repository’s 5,700 commits are mine.
- Oracle ERP integration, both directions: built the AR Invoice / AR Cash Receipt / Credit Note push out of the POS, and the inventory delta-pull workers that reconcile ERP lot data back into branch stock — a 48-state mapping over (lot status × warehouse locator), pulled on a deliberate overlap window rather than an exact high-water mark so clock skew and mid-transaction commits cannot drop rows.
- Financial correctness under concurrency (MSSQL): single-transaction repricing that also updates carts already holding the item, so nobody checks out at a stale price; daily branch revenue aggregation made idempotent by rolling back an order’s prior contribution before re-accumulating, using exact-decimal addition instead of float math.
- Thai full tax invoice (ใบกำกับภาษี): a 2,200-line renderer covering head-office versus branch designation and separate per-company VAT / non-VAT layouts, plus credit-note reporting.
- Operations tooling: a centralized alert gateway that normalizes failures from several internal systems into severity-routed Microsoft Teams cards, and PDPA consent gating at the point of sale.
- Partner sales-channel integration — API contract owner: designed the API surface a new sales channel used to transact against both the POS and the consumer gateway, wrote the module-level API specification, and built the service-to-service auth client (token acquire → cache → JWT-expiry decode → pre-emptive refresh). Introduced the channel as a first-class dimension across order routing, product publish state, payment-callback routing and employee purchase quotas. When the programme was cancelled I decommissioned it cleanly — ~2,750 lines across 19 files removed from one gateway alone, with both live systems staying up.
- Consumer API gateway (scoped): cart/checkout, catalog, customer, e-receipt and LINE LIFF modules inside a team-owned, no-framework PHP gateway serving the mobile app and e-commerce front ends.