How openWCS is built
You don't need to be an engineer to understand how openWCS works. This page is a plain-language tour: where openWCS sits in your warehouse, the small specialised parts it is made of, and the journey a single box takes from the loading dock to the outbound truck.
The big picture
Your business software — your WMS or ERP, the SAP or Manhattan system that knows what customers ordered — decides what needs to happen. Your machines on the floor — conveyors, storage cranes, robots, pick stations — actually move the goods. openWCS is the layer in between that turns "ship these orders" into the exact moves each machine must make, in the right order, in real time.
Made of small, focused parts
Instead of one enormous program, openWCS is a team of small services — think of them as specialists who each own one job and do it well. They cooperate by posting messages to a shared, tamper-proof logbook (the "event log") that every other part can read. If one specialist is busy or restarts, the others keep working.
Knows your products, packaging, storage locations and equipment — the facts everything else looks up.
Keeps the live count of every unit and where it sits — rebuilt from the logbook, so it's always auditable.
Takes in what must ship or be received, tracks each order's life, and releases it to the floor when it's ready.
Reserves the exact units for an order, works out cases vs. eaches, and packs them into the right cartons.
Chooses the best home for each incoming unit so fast movers stay close to the exit and aisles stay balanced.
Runs your warehouse processes — goods-in, outbound, counting — as flowcharts you draw and change yourself.
Turns a planned step into a concrete machine task and hands it to the right piece of equipment.
One small translator per machine type, so each vendor's quirks stay in one place — add a vendor, write an adapter.
Every move is written down, once, in order, and can never be edited — the single source of truth everything trusts.
Why this matters to you
The small-specialists design isn't just tidy engineering — it changes what you can do with the system you bought.
If one part needs a restart or an upgrade, the rest keep running. There's no single switch that takes the whole warehouse down.
Need a new machine, process or rule? You add or change one small part instead of re-writing everything. Growth doesn't mean a rebuild.
Equipment talks through swappable translators, so you're never married to one machine brand or one integrator's contract.
Every line is open and yours to run, read and change. Your data and your operating logic stay with you — leaving is never a rip-and-replace.
Runs anywhere, scales with you
Every service is stateless, so openWCS runs as many copies as the work demands behind any load balancer. It ships ready-to-apply Kubernetes manifests — deploy it, and let it grow and shrink with your warehouse.
Order waves of tens of thousands, or a floor full of conveyors scanning at once — add more copies of the busy service instead of buying a bigger machine. Capacity grows sideways, on demand.
Running several copies of each service means no single point of failure, and upgrades roll out copy-by-copy — so you can update in the middle of a shift with no downtime.
Autoscaling adds copies when traffic spikes and removes them when it's quiet, so you're not paying for peak-day hardware on a slow Sunday.
Standard Kubernetes runs on any cloud or your own data centre — no proprietary platform, no lock-in. The same open system, wherever you choose to run it.
Follow one box
Here's the same story from the floor's point of view — what happens to a single unit of goods from the moment it arrives to the moment it leaves on a truck. Each step is owned by one of the specialists above.
The map
The same picture as a simple map. Messages from your business systems come in at the top through one guarded front door; the specialists plan the work and write every move to the shared logbook; the floor dispatcher sends tasks out to the machines through their translators.
Three ideas worth knowing
If you remember three things from this page, make it these.
Every machine speaks its own dialect. An adapter is a thin translator that turns openWCS's single, uniform instruction into that machine's language. Swap the machine, swap the adapter — the rest of openWCS never changes.
Everything entering openWCS comes through a single gateway that checks who you are and what you're allowed to do. You can start relaxed for a pilot and tighten it for production — it's a setting, not a rebuild.
Every movement is written to an append-only log — entries are added, never edited or erased. It's the official history of your warehouse: fully auditable, and the live stock picture can always be rebuilt from it.
Open & yours to run
Every service, adapter and contract is open source. Read the code, run the whole stack on your own machines, and shape it to your warehouse.