diff --git a/src/Network/Wai/Middleware/Prometheus.hs b/src/Network/Wai/Middleware/Prometheus.hs
--- a/src/Network/Wai/Middleware/Prometheus.hs
+++ b/src/Network/Wai/Middleware/Prometheus.hs
@@ -47,8 +47,6 @@
     }
 
 {-# NOINLINE requestLatency #-}
--- XXX: https://prometheus.io/docs/practices/naming/ says this should be
--- _seconds, not _microseconds.
 requestLatency :: Prom.Metric (Prom.Vector Prom.Label3 Prom.Histogram)
 requestLatency = Prom.unsafeRegisterIO $ Prom.vector ("handler", "method", "status_code")
                                        $ Prom.histogram info Prom.defaultBuckets
diff --git a/wai-middleware-prometheus.cabal b/wai-middleware-prometheus.cabal
--- a/wai-middleware-prometheus.cabal
+++ b/wai-middleware-prometheus.cabal
@@ -1,5 +1,5 @@
 name:                wai-middleware-prometheus
-version:             0.2.0
+version:             0.3.0
 synopsis:
     WAI middlware for exposing http://prometheus.io metrics.
 description: