Work / 01
A customer service portal for energy data — built on systems that couldn’t be disturbed
An energy company wanted its customer service team to see a customer’s contracts, invoices, and usage at a glance. The information already existed, but it was spread across internal systems that were hard to search and never built for this.
Source systems · untouched
API layer · .NET
Customer service portal
Agents see the whole picture in one place, while the systems behind keep running as before.
Starting point
When a customer got in touch, the agent had to dig through several source systems to get the full picture. Those systems carried the rest of the business and could not be rebuilt. At the same time, answers had to be right: a wrong detail about an invoice quickly turns into another case. The platform also needed modernizing as new requirements came in.
What we did
We built an API layer in .NET/C# between the source systems and the portal. It fetches and combines contracts, invoices, and usage per customer, and Elasticsearch lets agents find the right customer and the right detail straight away. The portal only talks to the API layer — never directly to the internal systems. In parallel, we modernized the platform step by step.
Result
Customer service sees the whole picture in one place and can answer straight away instead of searching several systems. The internal systems carried on as before, and the clear separation means the portal can keep growing without changing the source systems.