Voltaris Energie
A customer portal for 180,000 households
Replacing a twelve-year-old portal in seven months, with zero downtime and a marked drop in calls to the service centre.
- support tickets per month
- −38%support tickets per month
- largest contentful paint (mobile)
- 1.2 slargest contentful paint (mobile)
- minutes of downtime during rollout
- 0minutes of downtime during rollout
The situation
The existing portal dated from 2013, ran on an unmaintained framework and was close to unusable on a phone. Yet more than 60 percent of traffic came from exactly there. Every meter reading that failed in the portal turned into a phone call — across roughly 180,000 households, that adds up.
How we worked
Rather than switching over in one go, we put the new portal in front of the old one route by route: meter readings first, then invoices, contract changes last. Each route went live on its own, initially for five percent of users. In parallel we built a design system the client's own team now uses to ship new pages.
- Strangler pattern: new routes placed in front of the legacy system step by step
- Mobile rethought from scratch rather than shrinking the desktop layout
- A 40-component design system, documented and maintained by the client's team
- Gradual rollout behind feature flags, reversible at any point
Outcome
Seven months after kickoff the last legacy route was retired. Support tickets about meter readings dropped sharply, the site loads on mobile in about a second, and the in-house team now publishes new content without us.
„We had braced ourselves for a big-bang relaunch. Instead the old system quietly disappeared and nobody noticed.“