TTT Inventory & Fulfillment System

The operations backbone of my own brand: an internal app that takes in orders from Shopify, Walmart, TikTok Shop, and Amazon, routes each to the right fulfillment hub, reserves the stock, and drives the pick/pack/label/ship workflow — with admin and hub-worker dashboards. It runs the brand's fulfillment today, and I keep building on it.

• 01A deterministic routing engine: consolidate an order to one hub when possible, else map by state, fall back by great-circle distance to the nearest hub, or split a multi-SKU order across hubs — anything unroutable drops into a manual-recovery queue instead of vanishing.
• 02Atomic inventory reservation that guards against overselling — order intake, task creation, and the stock commit run as one transaction; if any leg fails, the whole thing rolls back.
• 03Order intake from four marketplaces via signature-verified webhooks, plus EasyPost label creation and Shopify fulfillment/tracking write-back and marketplace inventory sync.
• 04Two role-based surfaces: an admin dashboard (exceptions, alerts, channel health, pending approvals, audit trail) and a hub dashboard (picking with barcode scan, packing, labels, returns, adjustments).
• 05A security model that moved all critical inventory logic out of the browser into server-side Edge Functions, behind row-level security and admin/hub authorization, with every stock change audit-logged.

Selling the same catalog across four marketplaces from multiple hubs is where DTC brands quietly bleed money — overselling, orders sent to the wrong hub, manual label chaos, and no clean audit trail. Off-the-shelf tools didn't fit how the brand actually ships, so I built the system it runs on.

Sole architect and developer. Routing engine, database + security model, marketplace integrations, both dashboards, and the fulfillment workflow — all me.

• ✓Handles my own brand's live orders across four marketplaces today — and I keep building on it.
• ✓50+ server-side Edge Functions on Supabase; Postgres with row-level security (tests assert cross-role access is denied); 84 migrations; an audit + transaction log on every inventory change.
• ✓The routing engine is a pure, tested function (state-map + great-circle fallback + multi-hub split); tests cover routing, auth, RLS, and workflow boundaries.

A deterministic routing algorithm, transactional inventory reservation that guards against overselling, four live marketplace integrations coordinated against one source of truth, and a security model where the sensitive logic lives server-side behind row-level security — the kind of internal platform a brand usually pays a team to build, running the operation I also own.