diff --git a/pkg/config/dynamic/middlewares.go b/pkg/config/dynamic/middlewares.go
index e01480e97..85c93d1f3 100644
--- a/pkg/config/dynamic/middlewares.go
+++ b/pkg/config/dynamic/middlewares.go
@@ -321,12 +321,15 @@ type RateLimit struct {
 	// The rate is actually defined by dividing Average by Period. So for a rate below 1req/s,
 	// one needs to define a Period larger than a second.
 	Average int64 `json:"average,omitempty" toml:"average,omitempty" yaml:"average,omitempty"`
+
 	// Period, in combination with Average, defines the actual maximum rate, such as:
 	// r = Average / Period. It defaults to a second.
-	Period types.Duration
+	Period types.Duration `json:"period,omitempty" toml:"period,omitempty" yaml:"period,omitempty"`
+
 	// Burst is the maximum number of requests allowed to arrive in the same arbitrarily small period of time.
 	// It defaults to 1.
-	Burst           int64            `json:"burst,omitempty" toml:"burst,omitempty" yaml:"burst,omitempty"`
+	Burst int64 `json:"burst,omitempty" toml:"burst,omitempty" yaml:"burst,omitempty"`
+
 	SourceCriterion *SourceCriterion `json:"sourceCriterion,omitempty" toml:"sourceCriterion,omitempty" yaml:"sourceCriterion,omitempty"`
 }