diff --git a/pkg/pipe/firehose.go b/pkg/pipe/firehose.go
index 1b5d995..5e17c1b 100644
--- a/pkg/pipe/firehose.go
+++ b/pkg/pipe/firehose.go
@@ -203,3 +203,25 @@ func Firehose(
 		}
 	}
 }
+
+type buffer struct {
+	IDs      []string
+	capacity int
+	write    int
+}
+
+func newBuffer(capacity int) *buffer {
+	return &buffer{
+		IDs:      make([]string, capacity),
+		capacity: capacity,
+	}
+}
+
+func (b *buffer) Add(ID string) {
+	b.IDs[b.write] = ID
+	b.write = (b.write + 1) % b.capacity
+}
+
+func (b *buffer) Contains(ID string) bool {
+	return slices.Contains(b.IDs, ID)
+}
diff --git a/pkg/pipe/utils.go b/pkg/pipe/utils.go
index 386f662..3a2bad3 100644
--- a/pkg/pipe/utils.go
+++ b/pkg/pipe/utils.go
@@ -7,7 +7,6 @@ import (
 	"log"
 	"os"
 	"os/signal"
-	"slices"
 	"syscall"
 
 	"github.com/nbd-wtf/go-nostr"
@@ -73,25 +72,3 @@ func shutdown(pool *nostr.SimplePool) {
 		return true
 	})
 }
-
-type buffer struct {
-	IDs      []string
-	capacity int
-	write    int
-}
-
-func newBuffer(capacity int) *buffer {
-	return &buffer{
-		IDs:      make([]string, capacity),
-		capacity: capacity,
-	}
-}
-
-func (b *buffer) Add(ID string) {
-	b.IDs[b.write] = ID
-	b.write = (b.write + 1) % b.capacity
-}
-
-func (b *buffer) Contains(ID string) bool {
-	return slices.Contains(b.IDs, ID)
-}