diff --git a/apps/payment/app_test.go b/apps/payment/app_internal_test.go
similarity index 100%
rename from apps/payment/app_test.go
rename to apps/payment/app_internal_test.go
diff --git a/apps/payment/randomizer_test.go b/apps/payment/randomizer_internal_test.go
similarity index 100%
rename from apps/payment/randomizer_test.go
rename to apps/payment/randomizer_internal_test.go
diff --git a/apps/payment/resolver_test.go b/apps/payment/resolver_internal_test.go
similarity index 100%
rename from apps/payment/resolver_test.go
rename to apps/payment/resolver_internal_test.go
diff --git a/backend/ethereum/wallet/address_test.go b/backend/ethereum/wallet/address_internal_test.go
similarity index 100%
rename from backend/ethereum/wallet/address_test.go
rename to backend/ethereum/wallet/address_internal_test.go
diff --git a/backend/sim/channel/channel_test.go b/backend/sim/channel/channel_internal_test.go
similarity index 100%
rename from backend/sim/channel/channel_test.go
rename to backend/sim/channel/channel_internal_test.go
diff --git a/backend/sim/channel/init_test.go b/backend/sim/channel/init_internal_test.go
similarity index 100%
rename from backend/sim/channel/init_test.go
rename to backend/sim/channel/init_internal_test.go
diff --git a/backend/sim/wallet/address_test.go b/backend/sim/wallet/address_internal_test.go
similarity index 100%
rename from backend/sim/wallet/address_test.go
rename to backend/sim/wallet/address_internal_test.go
diff --git a/channel/errors_test.go b/channel/errors_internal_test.go
similarity index 100%
rename from channel/errors_test.go
rename to channel/errors_internal_test.go
diff --git a/channel/funder_test.go b/channel/funder_internal_test.go
similarity index 100%
rename from channel/funder_test.go
rename to channel/funder_internal_test.go
diff --git a/channel/persistence/keyvalue/persistrestorer_test.go b/channel/persistence/keyvalue/persistrestorer_internal_test.go
similarity index 100%
rename from channel/persistence/keyvalue/persistrestorer_test.go
rename to channel/persistence/keyvalue/persistrestorer_internal_test.go
diff --git a/channel/persistence/test/channel_test.go b/channel/persistence/test/channel_internal_test.go
similarity index 100%
rename from channel/persistence/test/channel_test.go
rename to channel/persistence/test/channel_internal_test.go
diff --git a/channel/persistence/test/peerchans_test.go b/channel/persistence/test/peerchans_internal_test.go
similarity index 100%
rename from channel/persistence/test/peerchans_test.go
rename to channel/persistence/test/peerchans_internal_test.go
diff --git a/channel/test/app_randomizer_test.go b/channel/test/app_randomizer_internal_test.go
similarity index 100%
rename from channel/test/app_randomizer_test.go
rename to channel/test/app_randomizer_internal_test.go
diff --git a/client/chanregistry_test.go b/client/chanregistry_internal_test.go
similarity index 100%
rename from client/chanregistry_test.go
rename to client/chanregistry_internal_test.go
diff --git a/client/init_test.go b/client/init_internal_test.go
similarity index 100%
rename from client/init_test.go
rename to client/init_internal_test.go
diff --git a/client/proposal_internal_test.go b/client/proposal_internal_test.go
index f69f389b..62834c0d 100644
--- a/client/proposal_internal_test.go
+++ b/client/proposal_internal_test.go
@@ -18,6 +18,8 @@ import (
 	"math/rand"
 	"testing"
 
+	"github.com/pkg/errors"
+	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
 	"perun.network/go-perun/channel"
@@ -100,6 +102,33 @@ func TestChannelProposal_assertValidNumParts(t *testing.T) {
 	require.Error(c.assertValidNumParts())
 }
 
+func TestProposalResponder_Accept_Nil(t *testing.T) {
+	p := new(ProposalResponder)
+	_, err := p.Accept(nil, new(LedgerChannelProposalAcc))
+	assert.Error(t, err, "context")
+}
+
+func TestPeerRejectedProposalError(t *testing.T) {
+	reason := "some-random-reason"
+	err := newPeerRejectedError("update", reason)
+	t.Run("direct_error", func(t *testing.T) {
+		peerRejectedProposalError := PeerRejectedError{}
+		gotPeerRejectedError := errors.As(err, &peerRejectedProposalError)
+		require.True(t, gotPeerRejectedError)
+		assert.Equal(t, reason, peerRejectedProposalError.Reason)
+		assert.Contains(t, err.Error(), reason)
+	})
+
+	t.Run("wrapped_error", func(t *testing.T) {
+		wrappedError := errors.WithMessage(err, "some higher level error")
+		peerRejectedError := PeerRejectedError{}
+		gotPeerRejectedError := errors.As(wrappedError, &peerRejectedError)
+		require.True(t, gotPeerRejectedError)
+		assert.Equal(t, reason, peerRejectedError.Reason)
+		assert.Contains(t, err.Error(), reason)
+	})
+}
+
 func NewRandomBaseChannelProposal(rng *rand.Rand, opts ...channeltest.RandomOpt) BaseChannelProposal {
 	var opt channeltest.RandomOpt
 	if len(opts) != 0 {
diff --git a/client/proposal_test.go b/client/proposal_test.go
deleted file mode 100644
index 529db854..00000000
--- a/client/proposal_test.go
+++ /dev/null
@@ -1,50 +0,0 @@
-// Copyright 2020 - See NOTICE file for copyright holders.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package client
-
-import (
-	"testing"
-
-	"github.com/pkg/errors"
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-func TestProposalResponder_Accept_Nil(t *testing.T) {
-	p := new(ProposalResponder)
-	_, err := p.Accept(nil, new(LedgerChannelProposalAcc))
-	assert.Error(t, err, "context")
-}
-
-func TestPeerRejectedProposalError(t *testing.T) {
-	reason := "some-random-reason"
-	err := newPeerRejectedError("update", reason)
-	t.Run("direct_error", func(t *testing.T) {
-		peerRejectedProposalError := PeerRejectedError{}
-		gotPeerRejectedError := errors.As(err, &peerRejectedProposalError)
-		require.True(t, gotPeerRejectedError)
-		assert.Equal(t, reason, peerRejectedProposalError.Reason)
-		assert.Contains(t, err.Error(), reason)
-	})
-
-	t.Run("wrapped_error", func(t *testing.T) {
-		wrappedError := errors.WithMessage(err, "some higher level error")
-		peerRejectedError := PeerRejectedError{}
-		gotPeerRejectedError := errors.As(wrappedError, &peerRejectedError)
-		require.True(t, gotPeerRejectedError)
-		assert.Equal(t, reason, peerRejectedError.Reason)
-		assert.Contains(t, err.Error(), reason)
-	})
-}
diff --git a/client/proposalopts_test.go b/client/proposalopts_internal_test.go
similarity index 100%
rename from client/proposalopts_test.go
rename to client/proposalopts_internal_test.go
diff --git a/client/restore_test.go b/client/restore_internal_test.go
similarity index 100%
rename from client/restore_test.go
rename to client/restore_internal_test.go
diff --git a/client/test/channel_test.go b/client/test/channel_internal_test.go
similarity index 100%
rename from client/test/channel_test.go
rename to client/test/channel_internal_test.go
diff --git a/client/update_test.go b/client/update_internal_test.go
similarity index 100%
rename from client/update_test.go
rename to client/update_internal_test.go
diff --git a/client/updatemsgs_test.go b/client/updatemsgs_internal_test.go
similarity index 100%
rename from client/updatemsgs_test.go
rename to client/updatemsgs_internal_test.go
diff --git a/log/levellified_test.go b/log/levellified_internal_test.go
similarity index 100%
rename from log/levellified_test.go
rename to log/levellified_internal_test.go
diff --git a/log/log_test.go b/log/log_internal_test.go
similarity index 100%
rename from log/log_test.go
rename to log/log_internal_test.go
diff --git a/log/logrus/logrus_test.go b/log/logrus/logrus_internal_test.go
similarity index 100%
rename from log/logrus/logrus_test.go
rename to log/logrus/logrus_internal_test.go
diff --git a/log/none_test.go b/log/none_internal_test.go
similarity index 100%
rename from log/none_test.go
rename to log/none_internal_test.go
diff --git a/wire/account_test.go b/wire/account_internal_test.go
similarity index 100%
rename from wire/account_test.go
rename to wire/account_internal_test.go
diff --git a/wire/controlmsgs_test.go b/wire/controlmsgs_internal_test.go
similarity index 100%
rename from wire/controlmsgs_test.go
rename to wire/controlmsgs_internal_test.go
diff --git a/wire/msg_test.go b/wire/msg_internal_test.go
similarity index 100%
rename from wire/msg_test.go
rename to wire/msg_internal_test.go
diff --git a/wire/net/endpoint_test.go b/wire/net/endpoint_internal_test.go
similarity index 100%
rename from wire/net/endpoint_test.go
rename to wire/net/endpoint_internal_test.go
diff --git a/wire/net/endpoint_registry_test.go b/wire/net/endpoint_registry_internal_test.go
similarity index 100%
rename from wire/net/endpoint_registry_test.go
rename to wire/net/endpoint_registry_internal_test.go
diff --git a/wire/net/exchange_addr_test.go b/wire/net/exchange_addr_internal_test.go
similarity index 100%
rename from wire/net/exchange_addr_test.go
rename to wire/net/exchange_addr_internal_test.go
diff --git a/wire/net/mockconn_test.go b/wire/net/mockconn_internal_test.go
similarity index 100%
rename from wire/net/mockconn_test.go
rename to wire/net/mockconn_internal_test.go
diff --git a/wire/net/simple/dialer_test.go b/wire/net/simple/dialer_internal_test.go
similarity index 100%
rename from wire/net/simple/dialer_test.go
rename to wire/net/simple/dialer_internal_test.go
diff --git a/wire/net/simple/listener_test.go b/wire/net/simple/listener_internal_test.go
similarity index 100%
rename from wire/net/simple/listener_test.go
rename to wire/net/simple/listener_internal_test.go
diff --git a/wire/net/test/connhub_test.go b/wire/net/test/connhub_internal_test.go
similarity index 100%
rename from wire/net/test/connhub_test.go
rename to wire/net/test/connhub_internal_test.go
diff --git a/wire/net/test/dialer_test.go b/wire/net/test/dialer_internal_test.go
similarity index 100%
rename from wire/net/test/dialer_test.go
rename to wire/net/test/dialer_internal_test.go
diff --git a/wire/net/test/dialerlist_test.go b/wire/net/test/dialerlist_internal_test.go
similarity index 100%
rename from wire/net/test/dialerlist_test.go
rename to wire/net/test/dialerlist_internal_test.go
diff --git a/wire/net/test/listener_test.go b/wire/net/test/listener_internal_test.go
similarity index 100%
rename from wire/net/test/listener_test.go
rename to wire/net/test/listener_internal_test.go
diff --git a/wire/net/test/listenermap_test.go b/wire/net/test/listenermap_internal_test.go
similarity index 100%
rename from wire/net/test/listenermap_test.go
rename to wire/net/test/listenermap_internal_test.go
diff --git a/wire/receiver_test.go b/wire/receiver_internal_test.go
similarity index 100%
rename from wire/receiver_test.go
rename to wire/receiver_internal_test.go
diff --git a/wire/relay_test.go b/wire/relay_internal_test.go
similarity index 100%
rename from wire/relay_test.go
rename to wire/relay_internal_test.go