diff --git a/server-go/go.mod b/server-go/go.mod
index 7b8a4519..a2fd2bf7 100644
--- a/server-go/go.mod
+++ b/server-go/go.mod
@@ -6,10 +6,14 @@ require (
 	github.com/appleboy/gin-jwt/v2 v2.8.0
 	github.com/fatih/structs v1.1.0
 	github.com/gin-gonic/gin v1.7.7
+	github.com/google/uuid v1.3.0
 	github.com/jessevdk/go-flags v1.5.0
+	github.com/julianshen/gin-limiter v0.0.0-20161123033831-fc39b5e90fe7
+	github.com/robfig/cron/v3 v3.0.1
 	github.com/sirupsen/logrus v1.8.1
 	github.com/stretchr/testify v1.7.0
 	github.com/tidwall/gjson v1.14.0
+	gocloud.dev v0.24.0
 	golang.org/x/crypto v0.0.0-20220131195533-30dcbda58838
 	gorm.io/driver/postgres v1.2.3
 	gorm.io/gorm v1.22.5
@@ -44,7 +48,6 @@ require (
 	github.com/golang/protobuf v1.5.2 // indirect
 	github.com/google/go-cmp v0.5.6 // indirect
 	github.com/google/gofuzz v1.1.0 // indirect
-	github.com/google/uuid v1.3.0 // indirect
 	github.com/google/wire v0.5.0 // indirect
 	github.com/googleapis/gax-go/v2 v2.1.0 // indirect
 	github.com/googleapis/gnostic v0.5.5 // indirect
@@ -62,7 +65,6 @@ require (
 	github.com/jmespath/go-jmespath v0.4.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/juju/ratelimit v1.0.1 // indirect
-	github.com/julianshen/gin-limiter v0.0.0-20161123033831-fc39b5e90fe7 // indirect
 	github.com/leodido/go-urn v1.2.0 // indirect
 	github.com/mattn/go-isatty v0.0.12 // indirect
 	github.com/mattn/go-sqlite3 v1.14.9 // indirect
@@ -70,13 +72,11 @@ require (
 	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/robfig/cron/v3 v3.0.1 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
 	github.com/tidwall/match v1.1.1 // indirect
 	github.com/tidwall/pretty v1.2.0 // indirect
 	github.com/ugorji/go/codec v1.1.7 // indirect
 	go.opencensus.io v0.23.0 // indirect
-	gocloud.dev v0.24.0 // indirect
 	golang.org/x/net v0.0.0-20211209124913-491a49abca63 // indirect
 	golang.org/x/oauth2 v0.0.0-20210819190943-2bc19b11175f // indirect
 	golang.org/x/sys v0.0.0-20211029165221-6e7872819dc8 // indirect
diff --git a/server-go/storage/rotation.go b/server-go/storage/rotation.go
index 1f878503..6c718260 100644
--- a/server-go/storage/rotation.go
+++ b/server-go/storage/rotation.go
@@ -42,7 +42,6 @@ func (frs *FifoRotationStrategy) GetVersionsThatShouldBeDeletedIfThisVersionUplo
 	return existingVersions[0:1]
 }
 
-// todo: test reference
 func NewFifoRotationStrategy(collection *collections.Collection, existingVersions []UploadedVersion) *FifoRotationStrategy {
 	return &FifoRotationStrategy{
 		collection:       collection,
diff --git a/server-go/storage/rotation_test.go b/server-go/storage/rotation_test.go
index 82be0547..d59c0994 100644
--- a/server-go/storage/rotation_test.go
+++ b/server-go/storage/rotation_test.go
@@ -1 +1,30 @@
 package storage
+
+import (
+	"github.com/riotkit-org/backup-repository/collections"
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestNewFifoRotationStrategy_MutationTest(t *testing.T) {
+	collectionFirst := collections.Collection{}
+	versionsFirst := []UploadedVersion{
+		{Filename: "1.1"},
+	}
+
+	collectionSecond := collections.Collection{}
+	versionsSecond := []UploadedVersion{
+		{Filename: "2.1"},
+	}
+
+	// one object from factory will not impact second
+	strategyFirst := NewFifoRotationStrategy(&collectionFirst, versionsFirst)
+	strategySecond := NewFifoRotationStrategy(&collectionSecond, versionsSecond)
+
+	strategyFirst.collection.Metadata.Name = "first"
+	strategySecond.collection.Metadata.Name = "second"
+
+	assert.NotEqual(t, collectionFirst.Metadata.Name, collectionSecond.Metadata.Name)
+	assert.NotEqual(t, strategyFirst, strategySecond)
+	assert.NotEqual(t, &strategyFirst, &strategySecond)
+}