E-Commerce Marketplace Integrations¶
13 marketplace channels, 3 fulfillment providers, multiple advertising platforms — all wrapped behind a unified service. The Ecom-Sales / GogreenSellerAI (EcomFlow) app family is the heaviest user. Per Integrations_Audit.md, every marketplace listed has a dedicated service file with full API integration code.
The 13 marketplace channels¶
| Channel | API style | Notes |
|---|---|---|
| eBay | REST + Inventory API | Promoted Listings advertising integrated. |
| Etsy | Open API v3 + OAuth/PKCE | OAuth/PKCE because Etsy doesn't allow client-secrets in installed apps. |
| Amazon SP-API | AWS Sig V4 + LWA (Login with Amazon) | The most complex of the 13 — SP-API uses AWS request signing on top of LWA OAuth. PPC ads integrated. |
| Walmart | Marketplace API | US-only; competitive on B2C. |
| Shopify | Admin API | Used both as a channel (selling on partner Shopify stores) and as a platform (OpenSentinel ingests Shopify orders). |
| Facebook Shops | Commerce API | Through Meta's Graph API. |
| TikTok Shop | Seller Center API | Newest channel; high growth. |
| Google Shopping | Content API | Product feed + Shopping Ads. |
| Bonanza | Marketplace API | 3% FVF (final value fee). |
| Reverb | Musical-instruments marketplace | 5% fee. |
| Mercari | Mobile marketplace | 10% fee. |
| Poshmark | Clothing resale | 20% / $2.95 fee. |
| Depop | Fashion resale | 10% fee. |
Used in: Ecom-Sales, GogreenSellerAI / EcomFlow.
Pattern. Each channel is a service file src/services/marketplaces/{channel}.ts exposing:
listProducts(): Product[]
createListing(product): Listing
updateInventory(sku, qty)
fetchOrders(): Order[]
syncShipment(orderId, tracking)
MarketplaceService fans out and reconciles per-channel state with the local Postgres.
Shopify (special status)¶
Shopify shows up two ways: 1. As a sell-through channel in Ecom-Sales / GogreenSellerAI (above). 2. As an order-source for OpenSentinel — ingests Shopify orders for fraud/anomaly detection.
SDK: @shopify/shopify-api.
Fulfillment integrations¶
When you sell across 13 channels you don't want 13 warehouses.
| Provider | Role |
|---|---|
| ShipBob | 3PL — pick / pack / ship from regional fulfillment centers. |
| Deliverr (now part of Shopify) | Fast-shipping 3PL. |
| ShipMonk | 3PL with software for D2C / subscription brands. |
Used in: Ecom-Sales (all three; per-tenant choice).
Pattern. Order webhook arrives from a marketplace → unified order created in Postgres → fulfillment service routes the order to the configured 3PL → tracking number flows back to the marketplace via API.
Advertising integrations¶
| Platform | Linked to |
|---|---|
| eBay Promoted Listings | eBay channel |
| Amazon PPC | Amazon SP-API |
| Etsy Ads | Etsy channel |
| Google Shopping Ads | Google Content API |
Used in: Ecom-Sales / GogreenSellerAI.
Image generation for products¶
Every marketplace listing wants on-brand images: - DALL-E 3 — text → image (Ecom-Sales primary). - Stability AI — alternative provider (Ecom-Sales). - Sharp — server-side image resize / format conversion / variant generation.
See LLM-Providers.md and Document-Processing.md for the image pipeline.
Comparison alternatives (not used)¶
| Service | Notes |
|---|---|
| ChannelAdvisor / Sellbrite / Listing Mirror | Multi-channel listing tools — what Ecom-Sales is, but as SaaS. |
| WooCommerce / Magento / BigCommerce | E-commerce platforms. The portfolio's e-commerce is custom; these aren't ingest sources. |
| Faire / Joor / Tundra | Wholesale marketplaces. Out of scope. |
| Walmart DSV / Target+ | Drop-shipping channels — could be added later. |
Decision guide¶
Selling on more than two channels? Build a unified service like EcomFlow's.
Need 3PL fulfillment? ShipBob (regional), Deliverr (fast), ShipMonk (D2C).
Need product images at scale? DALL-E 3 + Sharp.
Need ads on the channels you sell on? Channel-specific advertising APIs (built-in to each service file).
"Should we just use Shopify multi-channel?" If your business fits in Shopify's box, yes — it ships these out of the box.