Data is maintained twice
Entering customers, orders or appointments in several systems wastes time and causes mistakes.
Services · E-commerce & development
Interfaces & API development
Connect systems without losing track of which script runs when. Interfaces and APIs with documentation, monitoring and clear error handling.
- Typical systems
- Shop, CRM, calendar, payments
- Methods
- REST APIs & webhooks
- Quality
- Logging & error handling
- Handover
- With documentation
Good integrations are invisible until they fail.
Orders flowing into inventory systems, bookings appearing in calendars and forms feeding newsletters save time every day. When a connection quietly fails, you may only notice when a customer contacts you.
I build integrations with error handling, retry logic, logging and documentation so you and others can understand what happens and when.
Does this sound familiar?
Automation is a black box
Scripts and Zapier chains nobody understands become risky when a system changes.
Errors are noticed too late
Without logs and alerts, missed orders or duplicate bookings can go unnoticed for days.
Typical integrations
Shop ↔ inventory / CRM
Transfer orders, customers and stock automatically, one way or in both directions.
Booking ↔ calendar
Synchronise appointments with Google or Outlook calendars, including conflict and time-zone handling.
Forms ↔ newsletter / email
Pass registrations with consent and double opt-in to mailing systems.
Payment webhooks
Process payment status reliably, including repeated or out-of-order notifications.
Internal microservices
Custom endpoints for workflows, reporting and data access, with authentication and rate limits.
Documentation & monitoring
Document endpoints, data flows and error cases, with logs and failure alerts.
What makes a reliable integration
Clear contracts
Every interface has a defined format: what data is exchanged, which fields are required and how errors are reported. A description such as an OpenAPI specification prevents misunderstandings between systems and teams.
Security
Authentication through API keys or OAuth, HTTPS encryption, minimal permissions and verified webhook signatures. Credentials are stored securely rather than in code.
Reliability
Networks fail and services respond slowly. Good integrations retry failed calls in a controlled way, safely handle duplicate messages through idempotency and report problems instead of hiding them.
Data protection
Integrations often transfer personal data between providers. I minimise data and document flows so processing agreements and privacy information can reflect them.
From outline to working integration
-
Map systems & data flows 2–3 days
Which systems are involved, and what data travels where and when?
-
Clarify authentication & contracts 2–3 days
Define access, API specifications, limits and error cases.
-
Implementation 1–4 weeks
Develop with tests, retry logic and logging.
-
Testing & monitoring 3–5 days
Test with real and simulated data and configure alerts.
-
Handover 1–2 days
Documentation, training and a maintenance and change plan.
When integrations are worthwhile
A good fit if
- You maintain data in several systems manually.
- You use shops, bookings or newsletters and want to automate workflows.
- You want integrations to be documented and understandable.
Probably not a fit if
- A single standard plugin already solves your problem; custom development is unnecessary.
- You expect integrations with systems that provide neither access nor an API.
Transparency about references
- Note Not publicly visible
Many integrations operate behind the scenes. If you need a reference, we can discuss which examples are approved for sharing. I do not invent client logos.
- See all cases
Interface and API questions
An Application Programming Interface is a defined connection through which systems exchange data or call functions, such as a shop passing orders to an inventory system.
A webhook is a notification one system automatically sends another when something happens, such as a successful payment. This avoids constant polling.
It depends on systems, data volume and error handling. Simple connections can be quick; complex synchronisation takes longer. You receive a fixed-price proposal after a review.
These tools are useful for simple workflows. Custom integrations can be better when volume, reliability, privacy or costs become more important. I advise on what fits your situation.
Through logging, retry logic, idempotency and error notifications, making problems visible and traceable.
I focus on data minimisation, secure transmission and documented flows. Discuss the legal assessment, including processing agreements, with your data protection adviser.
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