Stop typing the same stock number into seven emails.
You ship parts to a network of buyers. Each one asks the same questions through a different channel, what's in stock today, what's the ETA on that PO, was the order received. Your team spends half the week transcribing numbers from your ERP into reply emails. Upstream Inventory replaces that loop with one published view your subscribed buyers all read live.
The supplier-side asymmetry
One warehouse. N buyer relationships. Each asking the same questions.
Walmart suppliers got a vendor portal twenty years ago because Walmart could afford to build one. Everyone else lives in email, instant message, and Excel sheets that go stale the moment they're sent. The supplier carries the cost of the asymmetry: every buyer is a duplicate of the same operational question, multiplied by how many buyers carry your parts. Upstream Inventory is that portal, not built per-buyer, but shared across the network of buyers who already run on PowersportOS.
Inventory queries
Replaced by a live view every buyer reads from. You publish, they read.
ETA chases
Replaced by inbound batches with status + date. Set once, every buyer sees the same thing.
Order email threads
Replaced by submitted-in-app orders with PDF and a structured status workflow.
Per-buyer integrations
Replaced by one subscription model that scales with every new buyer who joins.
Most e-commerce platforms stop at the merchant's shelf. Upstream Inventory extends the model one tier up, to the factory or warehouse the merchant is buying from. Read the architecture
What you get
The buyer conversation, on autopilot.
A SUPPLIER tenant on PowersportOS runs a stripped sidebar focused on one thing: serving the downstream buyer relationships. No central catalog activation, no storefront features, no consumer-side concerns. The platform handles what every buyer relationship needs in common; you handle the parts that are specific to your business.
One inventory, every buyer
Maintain a single inventory row per SKU in your warehouse. Updates propagate live to every subscribed buyer the moment you save. No per-buyer allocation, no reservation, no double-promising. The mental model you hold is "what's in the warehouse", not "what I have promised to whom".
Inbound batches with ETAs
Stock you expect to receive (POs to your own factories, scheduled production runs, incoming containers) shows on every buyer's stock view with qty + earliest ETA. The "when is the next batch landing?" question gets answered before it gets asked. One-click transactional Receive when the stock actually lands.
Buyer-placed orders as PDFs
When a buyer submits an order in the app, your portal users get a Resend-sent email with a PDF order document attached. The order shows on your Dashboard and your Customers tab with a clean status workflow: PENDING, CONFIRMED, IN_PRODUCTION, FULFILLED. No more reconstructing what's in an email thread from three weeks ago.
Per-buyer subscription control
You decide which SKUs each buyer sees. Subscribe a buyer to the parts they actually carry; the rest of your warehouse stays invisible to them. Bulk-subscribe accepts up to 500 partNumbers in one paste, so onboarding a new buyer who brings a large existing assortment isn't a manual click-fest.
The shared-pool model
One warehouse number. Every buyer sees the same thing.
No allocation. By design.
Per-buyer allocation in a multi-buyer relationship leads to over-promising (every buyer thinks "their" stock is reserved) and under-utilisation (one buyer's allocated stock sits idle while another runs short). Upstream Inventory deliberately avoids the allocation model.
The supplier publishes one qty per SKU. If three buyers are subscribed to the same SKU and the warehouse holds 100 units, all three see 100. Whoever places an order against it first gets the stock; everyone else sees the qty drop in the same moment.
When a buyer genuinely needs reserved stock against a specific contract (a Q4 promotion, a long-tail planned drop), that's a conversation outside the platform for now. We'd rather hold the shared-pool model than ship a half-cooked allocation feature that breaks the supplier's mental model of "what's in the warehouse".
Shared-pool warehouse view. One row per SKU; updates propagate live to every subscribed buyer.
| SKU | Name | Qty | Box | UoM | Incoming |
|---|---|---|---|---|---|
| 55716013 | Air filter G3 Outlander 1000 | 847 | 12 | EA | — |
| 47716011 | Oil filter | 2,140 | 24 | EA | — |
| 55716088 | Air filter G3 X MR | 38 | 12 | EA | +100 |
| 703501249 | Brake pad set sintered | 512 | 10 | EA | — |
| 703500317 | Clutch spring kit | 156 | 8 | EA | — |
How it works
Publish once. Every subscribed buyer reads it live.
Your warehouse
Maintain one qty per SKU
PowersportOS
Shared-pool + buyer subscriptions
Buyers
Live stock + inbound ETAs
End customer
Catalog with real availability
One qty number. Read live by every subscribed buyer.
Orders arrive as PDFs, not as email-of-the-week
A buyer-placed order generates a server-rendered A4 PDF order document with the buyer's identity block, your supplier block, and the line items table. The PDF is attached to the email notification your portal users receive when the order arrives, and both sides can re-download from their own portal at any time. Your team has a packing slip the moment the order lands; no copy-paste from an inbox.
PURCHASE ORDER
BATCH-7K3F2A
Placed
2026-06-14
From
Northforge Powersports B.V.
Vesterhof 14
Almere, NL
VAT NL 0000 00 000 B00
To
Telgrim Manufacturing Co., Ltd
Zone 4, Building 12
Suzhou, China
orders@telgrim-mfg.example
| # | SKU | Description | Qty | Unit | Total |
|---|---|---|---|---|---|
| 1 | 55716013 | Air filter G3 Outlander 1000 · TELGRIM | 240 | 8.40 | 2,016.00 |
| 2 | 47716011 | Oil filter · TELGRIM | 480 | 3.20 | 1,536.00 |
| 3 | 55716088 | Air filter G3 X MR · TELGRIM | 120 | 9.10 | 1,092.00 |
| Total (USD) | 4,644.00 | ||||
Record of order placed via PowersportOS. Not a contract or invoice.
Status: PENDING · awaiting supplier confirmation
The Customers tab, your buyer command centre
One row per active contract. Drill into any customer to see the SKUs they're subscribed to, the shipments you've sent them, the orders they've placed, and the on-order rows that haven't shipped yet. The same UI for every buyer relationship, regardless of how many you carry; the supplier-side cost of adding a new buyer is one onboarding conversation, not a new integration build.
Active buyer-contracts. Drill in to subscribe parts, view shipments, and process orders.
| Customer | Country | Parts | Pending | Status |
|---|---|---|---|---|
| Northforge Powersports B.V. | NL | 16 | 1 | Awaiting confirm |
| Korvalaakso Motoring Oy | FI | 42 | 0 | Active |
| Stavnes Powersport AS | NO | 28 | 0 | Active |
| Westbrunn Motoren GmbH | DE | 19 | 0 | Active |
| Klangsjö Distribution AB | SE | 61 | 0 | Active |
What you don't have to build
The three things suppliers usually do instead.
A supplier who has grown past the email-and-Excel phase typically reaches for one of three solutions. Each one carries a cost that the supplier eats, with no shared benefit across buyers. Upstream Inventory replaces all three with one shared infrastructure that scales with the buyer network as it grows.
A custom supplier portal
Walmart-tier suppliers build them. Six to nine months of engineering, single-tenant, only serves the suppliers who happen to have the capital and the in-house team. Out of reach for most.
EDI per buyer
The old-school answer. Custom mapping per buyer's spec, brittle, expensive to maintain, requires both sides to commit. Falls apart the moment either side changes anything.
Exposed ERP API
You open a read-only endpoint on your ERP and hand the credential to each buyer. Works for the technical buyers, fails for the rest. Becomes a security review every time a new buyer onboards. Doesn't carry orders or ETAs, just stock counts.
Pricing
Suppliers pay. Buyer connections are free.
The value scales with how many buyers connect, not with how many SKUs or how much stock. A SUPPLIER tenant pays its own subscription; buyer-tenants get unlimited supplier connections included in their existing subscription. A retailer subscribed to seventeen different suppliers pays no extra; the heavy work happens on the supplier side, which is where the subscription sits.
Concrete numbers come from the onboarding conversation, scaled to the relevant buyer network. Talk pricing.
Want to be one of the first suppliers in the network?
We're working with a small group of factories, warehouses, and component manufacturers to seed the upstream side of the network. If you ship parts to multiple buyers and the supplier-side overhead has been growing with every new account, let's talk.