diff --git a/connect/utils_test.go b/connect/utils_test.go
index c3f5a96402695d1631aa4e43b7ecc29d58aaac48..8e7f31a8d6b2399cc01fbb1c43d0495723e41181 100644
--- a/connect/utils_test.go
+++ b/connect/utils_test.go
@@ -168,8 +168,10 @@ func (m *mockCmix) SendWithAssembler(recipient *id.ID, assembler cmix.MessageAss
 	cmixParams cmix.CMIXParams) (rounds.Round, ephemeral.Id, error) {
 	return rounds.Round{}, ephemeral.Id{}, nil
 }
-
-func (m *mockCmix) SendMany([]cmix.TargetedCmixMessage, cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+func (m *mockCmix) SendMany(messages []cmix.TargetedCmixMessage, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+	return rounds.Round{}, []ephemeral.Id{}, nil
+}
+func (m *mockCmix) SendManyWithAssembler(recipients []*id.ID, assembler cmix.ManyMessageAssembler, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
 	return rounds.Round{}, []ephemeral.Id{}, nil
 }
 func (m *mockCmix) AddIdentity(*id.ID, time.Time, bool)                       {}
diff --git a/dummy/mockCmix_test.go b/dummy/mockCmix_test.go
index aed2446c973fea4f753f62d6da717c13953ba2a7..3d6517f7961338fabea54127816e15bb5c9b7404 100644
--- a/dummy/mockCmix_test.go
+++ b/dummy/mockCmix_test.go
@@ -81,7 +81,12 @@ func (m mockCmix) GetMaxMessageLength() int {
 	return 100
 }
 
-func (m *mockCmix) SendMany(messages []cmix.TargetedCmixMessage, p cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+func (m *mockCmix) SendMany(messages []cmix.TargetedCmixMessage, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (m *mockCmix) SendManyWithAssembler(recipients []*id.ID, assembler cmix.ManyMessageAssembler, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
 	//TODO implement me
 	panic("implement me")
 }
diff --git a/e2e/fpGenerator_test.go b/e2e/fpGenerator_test.go
index c0f5c613a4397c70c39b0730d5d67fb301c83ba8..857fed38cd419c629cbb262c450a5a29ffddb7df 100644
--- a/e2e/fpGenerator_test.go
+++ b/e2e/fpGenerator_test.go
@@ -125,7 +125,10 @@ func (m *mockFpgCmix) SendWithAssembler(recipient *id.ID, assembler cmix.Message
 	cmixParams cmix.CMIXParams) (rounds.Round, ephemeral.Id, error) {
 	return rounds.Round{}, ephemeral.Id{}, nil
 }
-func (m *mockFpgCmix) SendMany([]cmix.TargetedCmixMessage, cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+func (m *mockFpgCmix) SendMany(messages []cmix.TargetedCmixMessage, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+	return rounds.Round{}, nil, nil
+}
+func (m *mockFpgCmix) SendManyWithAssembler(recipients []*id.ID, assembler cmix.ManyMessageAssembler, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
 	return rounds.Round{}, nil, nil
 }
 func (m *mockFpgCmix) AddIdentity(*id.ID, time.Time, bool) {}
diff --git a/e2e/rekey/utils_test.go b/e2e/rekey/utils_test.go
index aab5128b6cea8eb8cb067352c7e317b224155fce..e6ba2671ba29dcd9a09a1ce1be74c35b5d3c728b 100644
--- a/e2e/rekey/utils_test.go
+++ b/e2e/rekey/utils_test.go
@@ -245,8 +245,11 @@ func (m *mockNetManager) SendWithAssembler(recipient *id.ID, assembler cmix.Mess
 	return rounds.Round{}, ephemeral.Id{}, nil
 }
 
-func (m *mockNetManager) SendMany(messages []cmix.TargetedCmixMessage, p cmix.CMIXParams) (
-	rounds.Round, []ephemeral.Id, error) {
+func (m *mockNetManager) SendMany(messages []cmix.TargetedCmixMessage, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+	return rounds.Round{}, nil, nil
+}
+
+func (m *mockNetManager) SendManyWithAssembler(recipients []*id.ID, assembler cmix.ManyMessageAssembler, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
 	return rounds.Round{}, nil, nil
 }
 
diff --git a/e2e/utils_test.go b/e2e/utils_test.go
index d3a803e5e20c15daff06f87be614fbc4e90dbebe..bb63b070419f5653154ac9f8aae6b7bf2d281ad7 100644
--- a/e2e/utils_test.go
+++ b/e2e/utils_test.go
@@ -210,8 +210,10 @@ func (m *mockCmix) SendWithAssembler(recipient *id.ID, assembler cmix.MessageAss
 	cmixParams cmix.CMIXParams) (rounds.Round, ephemeral.Id, error) {
 	panic("implement me")
 }
-
-func (m *mockCmix) SendMany([]cmix.TargetedCmixMessage, cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+func (m *mockCmix) SendMany(messages []cmix.TargetedCmixMessage, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+	return rounds.Round{}, nil, nil
+}
+func (m *mockCmix) SendManyWithAssembler(recipients []*id.ID, assembler cmix.ManyMessageAssembler, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
 	return rounds.Round{}, nil, nil
 }
 func (m *mockCmix) AddIdentity(*id.ID, time.Time, bool) {}
diff --git a/fileTransfer/connect/utils_test.go b/fileTransfer/connect/utils_test.go
index f111e5268d7696b0ad2d4e5fc9697814829491dc..f62768d6fb7f23d144131a2c8051c8ef744e116e 100644
--- a/fileTransfer/connect/utils_test.go
+++ b/fileTransfer/connect/utils_test.go
@@ -118,9 +118,7 @@ func (m *mockCmix) Send(*id.ID, format.Fingerprint, message.Service, []byte,
 	[]byte, cmix.CMIXParams) (rounds.Round, ephemeral.Id, error) {
 	panic("implement me")
 }
-
-func (m *mockCmix) SendMany(messages []cmix.TargetedCmixMessage,
-	_ cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+func (m *mockCmix) SendMany(messages []cmix.TargetedCmixMessage, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
 	m.handler.Lock()
 	for _, targetedMsg := range messages {
 		msg := format.NewMessage(m.numPrimeBytes)
@@ -135,6 +133,10 @@ func (m *mockCmix) SendMany(messages []cmix.TargetedCmixMessage,
 	return rounds.Round{ID: 42}, []ephemeral.Id{}, nil
 }
 
+func (m *mockCmix) SendManyWithAssembler(recipients []*id.ID, assembler cmix.ManyMessageAssembler, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+	//TODO implement me
+	panic("implement me")
+}
 func (m *mockCmix) SendWithAssembler(*id.ID, cmix.MessageAssembler,
 	cmix.CMIXParams) (rounds.Round, ephemeral.Id, error) {
 	panic("implement me")
diff --git a/fileTransfer/e2e/utils_test.go b/fileTransfer/e2e/utils_test.go
index 38a6043ccab82ac96eeb942260194d6b6acc7ebf..47de2b6709a93c0fead7d4185b7aed5914ccd674 100644
--- a/fileTransfer/e2e/utils_test.go
+++ b/fileTransfer/e2e/utils_test.go
@@ -121,8 +121,7 @@ func (m *mockCmix) Send(*id.ID, format.Fingerprint, message.Service, []byte,
 	panic("implement me")
 }
 
-func (m *mockCmix) SendMany(messages []cmix.TargetedCmixMessage,
-	_ cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+func (m *mockCmix) SendMany(messages []cmix.TargetedCmixMessage, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
 	m.handler.Lock()
 	for _, targetedMsg := range messages {
 		msg := format.NewMessage(m.numPrimeBytes)
@@ -137,6 +136,11 @@ func (m *mockCmix) SendMany(messages []cmix.TargetedCmixMessage,
 	return rounds.Round{ID: 42}, []ephemeral.Id{}, nil
 }
 
+func (m *mockCmix) SendManyWithAssembler(recipients []*id.ID, assembler cmix.ManyMessageAssembler, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+	//TODO implement me
+	panic("implement me")
+}
+
 func (m *mockCmix) SendWithAssembler(*id.ID, cmix.MessageAssembler,
 	cmix.CMIXParams) (rounds.Round, ephemeral.Id, error) {
 	panic("implement me")
diff --git a/fileTransfer/groupChat/utils_test.go b/fileTransfer/groupChat/utils_test.go
index f4f3fd631e6bce3b50f44b2c9a89589e49841115..3ffdca7b2ee857467a47b02abcd87a627ebf161e 100644
--- a/fileTransfer/groupChat/utils_test.go
+++ b/fileTransfer/groupChat/utils_test.go
@@ -116,8 +116,7 @@ func (m *mockCmix) Send(*id.ID, format.Fingerprint, message.Service, []byte,
 	panic("implement me")
 }
 
-func (m *mockCmix) SendMany(messages []cmix.TargetedCmixMessage,
-	_ cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+func (m *mockCmix) SendMany(messages []cmix.TargetedCmixMessage, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
 	m.handler.Lock()
 	for _, targetedMsg := range messages {
 		msg := format.NewMessage(m.numPrimeBytes)
@@ -132,6 +131,11 @@ func (m *mockCmix) SendMany(messages []cmix.TargetedCmixMessage,
 	return rounds.Round{ID: 42}, []ephemeral.Id{}, nil
 }
 
+func (m *mockCmix) SendManyWithAssembler(recipients []*id.ID, assembler cmix.ManyMessageAssembler, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+	//TODO implement me
+	panic("implement me")
+}
+
 func (m *mockCmix) SendWithAssembler(*id.ID, cmix.MessageAssembler,
 	cmix.CMIXParams) (rounds.Round, ephemeral.Id, error) {
 	panic("implement me")
@@ -219,9 +223,9 @@ func (m *mockCmix) ChangeNumberOfNodeRegistrations(toRun int, timeout time.Durat
 	return nil
 }
 
-////////////////////////////////////////////////////////////////////////////////
+// //////////////////////////////////////////////////////////////////////////////
 // Mock Group Chat Manager                                                    //
-////////////////////////////////////////////////////////////////////////////////
+// //////////////////////////////////////////////////////////////////////////////
 type mockGcHandler struct {
 	services map[string]groupChat.Processor
 	sync.Mutex
diff --git a/fileTransfer/utils_test.go b/fileTransfer/utils_test.go
index 275d829ed67acf41a3dc4d925cebddfd738e568b..2d2e914311d6ab2cdf229d41d45daeccd8ddc788 100644
--- a/fileTransfer/utils_test.go
+++ b/fileTransfer/utils_test.go
@@ -170,8 +170,7 @@ func (m *mockCmix) Send(*id.ID, format.Fingerprint, message.Service, []byte,
 	panic("implement me")
 }
 
-func (m *mockCmix) SendMany(messages []cmix.TargetedCmixMessage,
-	_ cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+func (m *mockCmix) SendMany(messages []cmix.TargetedCmixMessage, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
 	m.handler.Lock()
 	defer m.handler.Unlock()
 	round := m.round
@@ -188,6 +187,10 @@ func (m *mockCmix) SendMany(messages []cmix.TargetedCmixMessage,
 	return rounds.Round{ID: round}, []ephemeral.Id{}, nil
 }
 
+func (m *mockCmix) SendManyWithAssembler(recipients []*id.ID, assembler cmix.ManyMessageAssembler, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+	//TODO implement me
+	panic("implement me")
+}
 func (m *mockCmix) SendWithAssembler(*id.ID, cmix.MessageAssembler,
 	cmix.CMIXParams) (rounds.Round, ephemeral.Id, error) {
 	panic("implement me")
diff --git a/groupChat/networkManager_test.go b/groupChat/networkManager_test.go
index 2f1f254d8f1e1702d8bbd4c0a7df7db028928023..c96ab995981c8d674df2c1175d6eda037d4aa7b6 100644
--- a/groupChat/networkManager_test.go
+++ b/groupChat/networkManager_test.go
@@ -44,7 +44,7 @@ func newTestNetworkManager(sendErr int) cmix.Client {
 	}
 }
 
-func (tnm *testNetworkManager) SendMany(messages []cmix.TargetedCmixMessage, _ cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+func (tnm *testNetworkManager) SendMany(messages []cmix.TargetedCmixMessage, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
 	if tnm.sendErr == 1 {
 		return rounds.Round{}, nil, errors.New("SendManyCMIX error")
 	}
@@ -66,6 +66,9 @@ func (tnm *testNetworkManager) SendMany(messages []cmix.TargetedCmixMessage, _ c
 	return rounds.Round{}, nil, nil
 }
 
+func (tnm *testNetworkManager) SendManyWithAssembler(recipients []*id.ID, assembler cmix.ManyMessageAssembler, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+	return rounds.Round{}, nil, nil
+}
 func (*testNetworkManager) AddService(*id.ID, message.Service, message.Processor) {}
 func (*testNetworkManager) IncreaseParallelNodeRegistration(int) func() (stoppable.Stoppable, error) {
 	return nil
diff --git a/ud/networkManager_test.go b/ud/networkManager_test.go
index 71be04b3607a7852ccf4a321a2cb549f2539cd66..0e42e5006a4230bfd00be247aa083b2e32cb4066 100644
--- a/ud/networkManager_test.go
+++ b/ud/networkManager_test.go
@@ -175,7 +175,12 @@ func (tnm *testNetworkManager) SendToAny(sendFunc func(host *connect.Host) (inte
 	panic("implement me")
 }
 
-func (tnm *testNetworkManager) SendMany(messages []cmix.TargetedCmixMessage, p cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+func (tnm *testNetworkManager) SendMany(messages []cmix.TargetedCmixMessage, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+	//TODO implement me
+	panic("implement me")
+}
+
+func (tnm *testNetworkManager) SendManyWithAssembler(recipients []*id.ID, assembler cmix.ManyMessageAssembler, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
 	//TODO implement me
 	panic("implement me")
 }
diff --git a/xxdk/utilsInterfaces_test.go b/xxdk/utilsInterfaces_test.go
index a0fb0ebde5edc14548b1ed76d881146cf1ac1518..d3d05eb1e3f1062b31ef4a9fbf7778d80fb1d3dc 100644
--- a/xxdk/utilsInterfaces_test.go
+++ b/xxdk/utilsInterfaces_test.go
@@ -56,7 +56,7 @@ func NewHistoricalRoundsComm() *historicalRounds {
 const failedHistoricalRoundID = 7
 const completedHistoricalRoundID = 8
 
-//  Mock comms endpoint which returns historical rounds
+// Mock comms endpoint which returns historical rounds
 func (ht *historicalRounds) RequestHistoricalRounds(host *connect.Host,
 	message *pb.HistoricalRounds) (*pb.HistoricalRoundsResponse, error) {
 	// Return one successful and one failed mock round
@@ -119,9 +119,10 @@ func (t *testNetworkManagerGeneric) SendWithAssembler(recipient *id.ID, assemble
 
 	return rounds.Round{}, ephemeral.Id{}, nil
 }
-
-func (t *testNetworkManagerGeneric) SendMany(messages []cmix.TargetedCmixMessage,
-	p cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+func (t *testNetworkManagerGeneric) SendMany(messages []cmix.TargetedCmixMessage, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
+	return rounds.Round{}, []ephemeral.Id{}, nil
+}
+func (t *testNetworkManagerGeneric) SendManyWithAssembler(recipients []*id.ID, assembler cmix.ManyMessageAssembler, params cmix.CMIXParams) (rounds.Round, []ephemeral.Id, error) {
 	return rounds.Round{}, []ephemeral.Id{}, nil
 }
 func (t *testNetworkManagerGeneric) GetInstance() *network.Instance {