diff --git a/src/interfaces/metric.hpp b/src/interfaces/metric.hpp
index 57a2b68..4e2fae3 100644
--- a/src/interfaces/metric.hpp
+++ b/src/interfaces/metric.hpp
@@ -19,6 +19,7 @@
     virtual void deinitialize() = 0;
     virtual std::vector<MetricValue> getReadings() const = 0;
     virtual LabeledMetricParameters dumpConfiguration() const = 0;
+    virtual uint64_t sensorCount() const = 0;
 };
 
 } // namespace interfaces