Build Custom AI for Multi-Channel Ecommerce Integration

Most SMBs start with a tool like Sellbrite or ChannelAdvisor. These platforms offer pre-built connectors to marketplaces like Amazon and eBay. The problem arises with custom business logic. For example, Sellbrite can sync inventory quantities but cannot handle bundled products where one component's stock level affects five different kits listed on three separate channels.

Consider an SMB selling custom-configured hardware on Shopify, Amazon, and a B2B portal. They use a 3PL for fulfillment which provides inventory via a daily CSV file on an FTP server. A customer on Shopify orders a kit with components A, B, and C. An Amazon order comes in for just component B. The Sellbrite sync runs every 15 minutes, but in that window, they can oversell component B, causing a stockout that impacts the Shopify kit order. The B2B portal orders are entered manually, creating another 2-hour delay before inventory is updated.

The structural issue is that these off-the-shelf tools are built for the 80% use case: simple quantity syncing between major platforms. Their architecture uses polling, checking for updates on a fixed schedule. They cannot use webhooks for real-time updates from every source, especially legacy systems like an FTP server or a custom B2B portal. They also lack the logic to handle complex dependencies like product bundling or tiered pricing rules that vary by channel.

The result is constant manual reconciliation. An employee spends 1-2 hours daily cross-referencing sales reports with inventory levels, manually adjusting stock on each channel. This leads to overselling, which damages marketplace ratings, and underselling, which leaves money on the table. The cost is not just labor; it's lost revenue and customer trust.

The engagement begins with a systems audit. Syntora maps every sales channel, inventory source, and order management system you use. We document the API capabilities of each, identifying which support real-time webhooks and which require scheduled polling. This audit produces a data flow diagram and an integration plan you approve before any code is written.

The core would be a central FastAPI service deployed on AWS Lambda for event-driven processing. When an order hits Shopify, a webhook triggers the service instantly. The service uses Pydantic for data validation and calls the Amazon Selling Partner API to decrement inventory. For systems without APIs, like a 3PL's FTP server, a scheduled Lambda function runs every 60 seconds to parse the CSV and update a central inventory ledger in a Supabase Postgres database. This hybrid webhook and polling model provides the fastest possible updates for each specific channel.

The final deliverable is not just code, but a managed system. You get a private GitHub repository with the full Python source code, a runbook for maintenance, and a simple Vercel-hosted dashboard showing sync status and any API errors. The system integrates directly with your existing tools, so your team's workflow does not change. They just see accurate, real-time inventory on every channel.