PIPELINEGuide
Connecting API integrations with existing systems
Does everything need to be replaced for this? Usually not. What can be connected to an existing system landscape, where the limits are, and which part typically takes the longest.
In most cases, nothing existing needs to be replaced for API integrations: ERP, CRM, calendar, accounting, or phone systems are connected via interfaces. What matters is whether the respective system has a documented interface — and the time-critical part is almost never the technology, but obtaining the access credentials.
01 — Integration
Connection with existing systems
The most common misconception is that everything must be replaced. In most cases, the existing system landscape remains in place, and API integrations build on top of it — through interfaces, not through replacement.
What gets connected in practice: ERP, CRM, calendar, accounting, phone system, newsletter system, website. What matters is whether the respective system has a documented interface. Where none exists, there's usually a workaround — but that costs effort and needs to be clarified up front, not discovered later.
The time-critical part is almost never the technical integration, but obtaining access credentials. Starting early here noticeably shortens the project timeline.
02 — Requirements
What you need for an API integration
- A clearly defined trigger. Not “we should do something with AI,” but a process that demonstrably costs time or orders today.
- Existing content or data. API integrations work with what's there. The more complete the starting point, the shorter the setup.
- Access to the systems involved. Whoever manages the credentials needs to be involved from the start — this is, in our experience, the most common cause of delays.
- One decision-making contact person. One, not three.
- Willingness to refine after launch. The first weeks in real operation show what was missing in the concept. That's normal and accounted for.
03 — Bottlenecks
What typically causes delays
- Content and deliveries. By far the most common cause of delay. Text, images, price lists, access credentials — what's missing blocks progress.
- Decisions. When it's unclear who approves, the project waits. A named contact person with decision-making authority noticeably shortens the timeline.
- Access to third-party systems. Getting access to inventory management, phone systems, or CRM regularly takes longer than the integration itself.
- Endless review rounds. Two correction rounds are normal, five are a sign that the goal wasn't clear at the start.
04 — Questions
Frequently asked questions
Can multiple systems be connected simultaneously?
Yes, that's actually the more common case — for example, shop, inventory management, and accounting together. Each connection is planned and tested individually, even if everything works together in the end.
What if our legacy system has no interface?
Then there are usually workarounds: database access, automated file exchange, in exceptional cases surface automation. All are more fragile than a real interface. We'll honestly tell you how stable such a solution will be before you decide.
How often is data synchronized?
From immediately to nightly — depending on what's technically necessary. Immediate synchronization isn't always better: for systems with post-processing, a nightly run is often the more stable choice.
What does maintenance cost during operation?
As long as none of the connected systems changes fundamentally, ongoing effort is low — monitoring reports itself when something doesn't fit.
Is an interface more secure than a manual export?
Significantly, because human errors during export and import are eliminated and every exchange is logged. A manual export leaves no trace if something was overlooked.
What happens during an outage?
The connection remembers what hasn't been transferred yet, tries again, and reports after multiple failed attempts. Data isn't lost, it arrives delayed.
Who maintains it later?
You receive code and documentation. We deliberately build with widely used technologies so that switching is possible.
05 — Next
Related pages
- API Interfaces — Overview
- API Interfaces — Alternatives
- API Interfaces — Small Businesses
- API Interfaces — Funding
- API Interfaces — Practical Examples
- API Interfaces — Provider Comparison
- API integrations — data protection
- API Interfaces — Cost-effectiveness
- Process automation
- Custom software
- CRM integration
- All guides
Next step
We'll look at your starting position.
Tell us what's eating up time today. That becomes an assessment with effort and benefit — and only then an offer.