Energy monitoring projects often start with one simple request: show the current power reading in a dashboard. The first version is usually straightforward. Poll a meter, parse its response, and draw a chart. The trouble starts later, when the meter changes, a second inverter is added, or the same data needs to reach both a local dashboard and a cloud service. At that point, device-specific code tends to spread everywhere. A more durable design is to separate the system into four small ...