diff --git a/rx/observable-operator-run_test.go b/rx/observable-operator-run_test.go
new file mode 100644
index 0000000..ee16bba
--- /dev/null
+++ b/rx/observable-operator-run_test.go
@@ -0,0 +1,57 @@
+package rx_test
+
+import (
+	"context"
+
+	"github.com/fortytw2/leaktest"
+	. "github.com/onsi/ginkgo/v2" //nolint:revive // ginkgo ok
+	. "github.com/onsi/gomega"    //nolint:revive // gomega ok
+)
+
+var _ = Describe("Observable operator", func() {
+	Context("Run", func() {
+		When("principle", func() {
+			It("🧪 should: ", func() {
+				// rxgo: Test_Observable_Run
+				defer leaktest.Check(GinkgoT())()
+
+				ctx, cancel := context.WithCancel(context.Background())
+				defer cancel()
+
+				s := make([]int, 0)
+				<-testObservable[int](ctx, 1, 2, 3).Map(
+					func(_ context.Context, i int) (int, error) {
+						s = append(s, i)
+
+						return i, nil
+					},
+				).Run()
+
+				Expect(s).To(ContainElements([]int{1, 2, 3}))
+			})
+		})
+
+		Context("Errors", func() {
+			When("error", func() {
+				It("🧪 should: ", func() {
+					// rxgo: Test_Observable_Run_Error
+					defer leaktest.Check(GinkgoT())()
+
+					ctx, cancel := context.WithCancel(context.Background())
+					defer cancel()
+
+					s := make([]int, 0)
+					<-testObservable[int](ctx, 1, errFoo).Map(
+						func(_ context.Context, i int) (int, error) {
+							s = append(s, i)
+
+							return i, nil
+						},
+					).Run()
+
+					Expect(s).To(ContainElements([]int{1}))
+				})
+			})
+		})
+	})
+})
diff --git a/rx/observable-operator.go b/rx/observable-operator.go
index cd7933d..541107f 100644
--- a/rx/observable-operator.go
+++ b/rx/observable-operator.go
@@ -183,32 +183,6 @@ func (o *ObservableImpl[T]) Connect(ctx context.Context) (context.Context, Dispo
 	return ctx, Disposable(cancel)
 }
 
-// Run creates an Observer without consuming the emitted items.
-func (o *ObservableImpl[T]) Run(opts ...Option[T]) Disposed {
-	dispose := make(chan struct{})
-	option := parseOptions(opts...)
-	ctx := option.buildContext(o.parent)
-
-	go func() {
-		defer close(dispose)
-
-		observe := o.Observe(opts...)
-
-		for {
-			select {
-			case <-ctx.Done():
-				return
-			case _, ok := <-observe:
-				if !ok {
-					return
-				}
-			}
-		}
-	}()
-
-	return dispose
-}
-
 func (o *ObservableImpl[T]) Contains(equal Predicate[T], opts ...Option[T]) Single[T] {
 	const (
 		forceSeq     = false
@@ -1641,6 +1615,32 @@ func (o *ObservableImpl[T]) Retry(count int, shouldRetry ShouldRetryFunc, opts .
 	}
 }
 
+// Run creates an Observer without consuming the emitted items.
+func (o *ObservableImpl[T]) Run(opts ...Option[T]) Disposed {
+	dispose := make(chan struct{})
+	option := parseOptions(opts...)
+	ctx := option.buildContext(o.parent)
+
+	go func() {
+		defer close(dispose)
+
+		observe := o.Observe(opts...)
+
+		for {
+			select {
+			case <-ctx.Done():
+				return
+			case _, ok := <-observe:
+				if !ok {
+					return
+				}
+			}
+		}
+	}()
+
+	return dispose
+}
+
 // !!!
 
 // ToSlice collects all items from an Observable and emit them in a slice and
diff --git a/rx/observable.go b/rx/observable.go
index 9d3dc52..dee6c3f 100644
--- a/rx/observable.go
+++ b/rx/observable.go
@@ -43,10 +43,10 @@ type Observable[T any] interface {
 	OnErrorResumeNext(resumeSequence ErrorToObservable[T], opts ...Option[T]) Observable[T]
 	OnErrorReturn(resumeFunc ErrorFunc[T], opts ...Option[T]) Observable[T]
 	OnErrorReturnItem(resume T, opts ...Option[T]) Observable[T]
-	Run(opts ...Option[T]) Disposed
 	Reduce(apply Func2[T], opts ...Option[T]) OptionalSingle[T]
 	Repeat(count int64, frequency Duration, opts ...Option[T]) Observable[T]
 	Retry(count int, shouldRetry ShouldRetryFunc, opts ...Option[T]) Observable[T]
+	Run(opts ...Option[T]) Disposed
 	ToSlice(initialCapacity int, opts ...Option[T]) ([]Item[T], error)
 }