Integrations & Interfaces
Modern e-commerce systems are not islands — they're the digital hub connecting ERP, CRM, marketplaces, payment providers, logistics partners, and marketing tools.
Integrations That Actually Connect
A well-designed API integration architecture determines whether those connections are reliable, low-maintenance, and extensible. We plan and implement interfaces that run stably, ensure data consistency, and let you onboard new partners or services quickly without major rework.
The essentials of Integrations & Interfaces
- We plan and implement interfaces to ERP, CRM, marketplaces, payment providers, logistics and marketing tools, so data syncs in real time and manual transfers disappear.
- We build the architecture for failure: circuit breakers, timeouts and retry logic with backoff isolate a stalling third party instead of letting it drag your checkout down.
- Anything the customer doesn't need immediately – ERP transfer, shipping notification, CRM sync – runs asynchronously through a queue, so the slowest service doesn't dictate checkout load time.
- Idempotent endpoints prevent duplicate orders, and monitoring for missing or failed events catches the silent failures that let systems quietly drift apart.
- We secure connections with OAuth 2.0, API key rotation and encrypted transmission, and document all data flows in a GDPR-compliant way, including data processing agreements.
Real E-Commerce Successes
- Order data, inventory, and customer records drift apart across systems because manual transfers are error-prone and delayed.
- A third-party service — payment provider, shipping carrier, or ERP — went down and blocked your entire checkout or order processing with it.
- You have no visibility into when a third-party changes their API, and you only notice problems when orders or data syncs silently fail.
Integrations & Interfaces: services in detail
- ERP IntegrationWithout a reliable ERP integration, you manage prices, inventory, and orders twice over — error-prone, time-delayed, and hostile to scale. We integrate your Shopware shop with SAP, Microsoft Dynamics, Xentral, Sage, or other ERP systems so data syncs in real time and manual transfers become a thing of the past. Your shop always works with current data; your team gains time for tasks that actually create value.Learn more
- PIM IntegrationProduct data maintained in multiple systems is a persistent quality problem: inconsistent copy, missing attributes, outdated images. We integrate your PIM system — Akeneo, Contentserv, Pimcore, or another — bidirectionally with your Shopware shop so the shop always receives the current, complete product data from the PIM. Your team edits once; the shop shows it everywhere.Learn more
- Payment IntegrationMissing or cumbersome payment methods cost orders — right at the moment of highest purchase intent. We integrate the payment providers relevant to your audience into your Shopware shop: Stripe, PayPal, Klarna, local payment methods, SEPA direct debit, and purchase on account. We focus on friction-free checkout integration, PCI compliance, and error handling that protects the customer experience even when a payment fails.Learn more
Interfaces for custom software
We don't build interfaces for online shops only. As soon as a business application, a customer portal or an internal tool shares data with other systems, the same rules apply: versioned contracts, clean error handling and monitoring. When we build custom software, we plan its integrations from day one instead of bolting them on at the end.
ERP and inventory
Orders, stock, prices and invoices flow between the application and the ERP, often in both directions. We define which system owns which field and make every transfer idempotent, so a retry never creates duplicates. Typical cases are covered on our ERP integration page.
CRM and PIM
Leads, contacts and contract states should land where sales actually works. Product data comes from a PIM as the leading system and feeds shop, customer portal and field-sales app, instead of every application keeping its own copy. We only transfer the fields that are really needed.
Payment and billing
Payments, subscriptions and credit notes need especially careful error handling, because payment-provider webhooks can arrive twice or late. We process them idempotently and reconcile the payment status with the provider regularly, so accounting and application see the same numbers.
Internal and legacy systems
A lot of data lives in in-house software, databases or file exports without a modern interface. We wrap such systems behind a dedicated REST API or adapter so new applications can connect cleanly. When several systems have to work together, it becomes a system integration project.
How an integration is built
Before a single line of code is written, we clarify data flows, failure scenarios, and legal requirements. Only then does implementation begin — with a clear architecture plan as the foundation.
Inventory & data-flow analysis
Which systems need connecting, which data flows in which direction, and what dependencies exist between services?
Architecture decision: sync vs. async
What must run synchronously in the request-response cycle, and what belongs in a queue? This split determines checkout performance and failure behaviour.
Failure & compliance design
Circuit breakers, timeouts, retry logic, and idempotency are planned; GDPR requirements and data-processing agreements are verified for every data flow.
Implementation & testing
Building the interfaces including failure scenarios, contract tests against external APIs, and load tests for critical paths.
Monitoring & proactive maintenance
Alerting on missing events, tracking third-party API changelogs, and adapting to breaking changes before anything fails silently.
Each phase builds on the outputs of the previous one; skipping ahead creates technical debt.
Where integration architecture puts its focus
Not every aspect of an integration architecture contributes equally to stability. This weighting shows where design focus should be concentrated.
- Failure isolation (circuit breakers, timeouts)A third-party outage must not block the checkout
- Async / sync separationQueue-based post-processing decouples systems from each other
- Data consistency & idempotencyDuplicate transmissions must not create duplicate orders
- Monitoring for silent failuresInterfaces rarely fail loudly — alert on missing events
- GDPR & data-processing agreementsLegal basis required for every third-party data flow
Relative weighting
Values are relative design weightings — not measured outcomes.
What matters in API integration and interfaces
A good integration plans for failure, not for the ideal case. External services go down, respond slowly or change their behaviour, and the architecture has to be built around exactly that. Circuit breakers, timeouts and retry logic with backoff make sure a stalling third party does not drag your checkout down with it. The goal is not to prevent outages but to isolate them.
The most important decision is what runs synchronously in the request and what does not. Anything the customer does not need immediately belongs in a queue: ERP transfer, shipping notification, CRM sync. That way the slowest service no longer dictates checkout load time, and a briefly unreachable system means delayed processing rather than a lost order.
Data consistency is the invisible discipline. Idempotent endpoints stop a repeated transfer from creating duplicate orders, and clean handling of partial failures stops systems from quietly drifting apart. Interfaces rarely fail loudly; they fail silently, which is exactly why you need monitoring for missing or failed events.
Every data flow needs a legal view alongside the technical one. The moment personal data goes to a third party, you need a legal basis and usually a data processing agreement. That covers not just marketing tools but also shipping, payment and analytics. Clarify it only after launch and you have built a compliance problem straight into the architecture.
Circuit breakers isolate failures
A circuit breaker pattern disconnects a failing external service from the rest of the platform once error rates cross a threshold. This prevents a slow or unreachable third party from taking down the entire platform — checkout and core processes continue while the external service recovers.
Async processing decouples systems
When API calls happen synchronously inside the checkout request cycle, the slowest external service determines the checkout load time. Queue-based asynchronous processing decouples order confirmation from downstream actions like ERP transfer or shipping notification — the customer gets an immediate response.
GDPR applies to third-party data flows
Every transfer of personal data to a third party requires a legal basis and typically a data processing agreement. This applies not just to CRM and email marketing tools, but also to shipping carriers, payment processors, and analytics services that handle customer data.
Every system in sync
Integrations decide whether your shop is a hub or an island. We build interfaces that stay stable even when third parties fail — with monitoring instead of hoping.
One data flow
Shop, ERP, CRM and logistics speak the same language — no more double entry.
Securely connected
OAuth 2.0 and encryption protect every API connection.
Stable under failure
Asynchronous processing keeps checkout fast even when a third-party system stalls.
Proactively maintained
We watch API changelogs and update before anything breaks.
Frequently asked questions
Your question isn't here? Ask us directly
Which third-party systems do you typically integrate?
Our range covers payment providers (Stripe, PayPal, Klarna), shipping services (DHL, DPD, UPS), ERP systems (SAP, Microsoft Dynamics, Xentral), PIM systems, CRM platforms, and marketplace APIs (Amazon, eBay). If a system has an API, we can connect it.
What happens when a third-party provider changes their API?
That's one of the most common causes of silent failures in integrated systems. We subscribe to API changelogs and release notes from all connected providers and systematically test changes in a staging environment before they reach production. You're proactively informed as soon as a relevant change is on the horizon.
Can a broken third-party API crash my shop?
Not with a robust integration architecture. We implement circuit breakers, retry logic, and fallback mechanisms so that a failed external service is isolated and your core processes continue uninterrupted. Critical actions like checkout are protected so they work even without temporarily available third-party data.
How long does a typical API integration take?
Simple integrations with well-documented REST APIs can often be completed in one to two weeks. Complex ERP integrations with bidirectional data exchange, custom field mapping, and extensive test scenarios can take several months. We provide realistic estimates after an initial requirements conversation.
Is GDPR-compliant API integration possible?
Yes, and it's a mandatory part of every integration we deliver. We document all data flows and processing purposes, clarify data processing agreements with third-party providers, and ensure personal data is only transferred to the extent necessary for the specific purpose at hand.
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Online shop, business application or internal system: tell us which systems need to talk to each other, and we'll outline how to connect them reliably.
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