weclapp Setup and Shop Sync at Excase

Starting point

Excase is an established B2B supplier in the industrial space with its own online shop. Classic mid-market setup: grown business, established customer base, an assortment that has broadened over the years. The shop had proven itself as a sales channel — but the backend behind the shop hadn’t kept pace with growth.

Concretely, this meant: the shop had its own stock system because that had originally been the simplest solution. The warehouse system (the older inventory program) had its own stock system. Both systems were synchronized manually — someone regularly checked whether the levels still matched and corrected differences. With every order, status updates also had to be maintained manually in both systems.

The problem: duplicate maintenance is not only expensive, it’s unreliable. Data drifts regularly, especially during peak times or when someone is sick. In B2B, an incorrectly stated stock is more expensive than in B2C — when an industrial customer gets a confirmed order and the item is actually not deliverable, that costs trust.

Discovery & architecture

The discovery workshop was a classic “world-square” session: sales, warehouse, accounting, management. The main question was not “do we need a new ERP?” — that was clear beforehand — but “how do we introduce it without endangering ongoing operations?”.

Three architectural decisions shaped the setup:

1. weclapp becomes the leading source. Stock, conditions, customer master data live in the ERP. The shop is a data consumer, not a producer. With that, the question “which system is right?” is answered for good.
2. Real-time sync, not batch sync. Instead of loading the shop with stock at night (which leads to inconsistencies during business hours), sync runs bidirectionally via webhooks. An order, a goods receipt, a return — everything mirrors in both systems within seconds.
3. Consistency check as a safety net. We don’t trust webhooks blindly — a lost webhook would create data drift that might only surface weeks later. Hourly reconciliation aligns both systems and reports differences.

Implementation

Phase 1 was master-data migration: products, stock levels, customers, open orders, conditions. At Excase, special attention was needed for B2B conditions — wholesale customers get different price tiers, special conditions, individual payment terms. We modeled this logic cleanly in weclapp so that every sales rep sees the correct conditions without having to ask.

Phase 2 was the shop integration. Incoming orders are taken into weclapp via the shop API — automatically created as orders, assigned to the right customer, queued in the dispatch pool. Stock changes in weclapp are synchronized back to the shop in real time. Returns are booked back through a separate workflow: goods receipt in weclapp → stock increase → sync to the shop.

Phase 3 was accounting. With weclapp as the central ERP, the DATEV handover runs directly — invoices are generated automatically, exported in DATEV format, the tax advisor gets a clean data stream. Previously this was a manual monthly reconciliation; now it runs daily.

Training was intensive because the team has to work with the ERP every day. We offered two sessions per role (sales, warehouse, accounting) — the first directly before go-live, the second two weeks afterwards for detail questions. After the second session it was clear: the system runs, the team has it in hand, additional training would be over-engineering.

Result

Today, duplicate maintenance at Excase is abolished. An order is captured once and runs through — warehouse, dispatch, invoicing, DATEV. Stock is identical in shop and ERP, the consistency check has reported no differences for months. The sales team sees the correct conditions and current stock for each customer at a glance.

What we like about this case: it has no sensation. There was no new business model, no spectacular innovation — Excase wanted a cleanly running ERP that finally connects shop and warehouse. We delivered that. Architecture that simply works is the most unspectacular and at the same time most useful form of IT work.