diff --git a/pkg/extension/luahost/pool_test.go b/pkg/extension/luahost/pool_test.go
index 73d37cb..9e936ea 100644
--- a/pkg/extension/luahost/pool_test.go
+++ b/pkg/extension/luahost/pool_test.go
@@ -47,7 +47,7 @@ func TestPoolGrowsWithPuts(t *testing.T) {
 	require.NoError(t, err)
 	b, err := pool.getState()
 	require.NoError(t, err)
-	assert.Equal(t, 0, len(pool.states), "Wanted pool to be empty")
+	assert.Empty(t, pool.states, "Wanted pool to be empty")
 
 	pool.putState(a)
 	pool.putState(b)
@@ -64,11 +64,11 @@ func TestPoolPutDiscardsClosed(t *testing.T) {
 
 	a, err := pool.getState()
 	require.NoError(t, err)
-	assert.Equal(t, 0, len(pool.states), "Wanted pool to be empty")
+	assert.Empty(t, pool.states, "Wanted pool to be empty")
 
 	a.Close()
 	pool.putState(a)
-	assert.Equal(t, 0, len(pool.states), "Wanted pool to remain empty")
+	assert.Empty(t, pool.states, "Wanted pool to remain empty")
 }
 
 func TestPoolPutClearsStack(t *testing.T) {
@@ -76,7 +76,7 @@ func TestPoolPutClearsStack(t *testing.T) {
 
 	ls, err := pool.getState()
 	require.NoError(t, err)
-	assert.Equal(t, 0, len(pool.states), "Wanted pool to be empty")
+	assert.Empty(t, pool.states, "Wanted pool to be empty")
 
 	// Setup stack.
 	ls.Push(lua.LNumber(4))
@@ -85,7 +85,7 @@ func TestPoolPutClearsStack(t *testing.T) {
 
 	// Return and verify stack cleared.
 	pool.putState(ls)
-	assert.Equal(t, 1, len(pool.states), "Wanted pool to have one item")
+	assert.Len(t, pool.states, 1, "Wanted pool to have one item")
 	require.Equal(t, 0, ls.GetTop(), "Want stack to be empty")
 }
 
diff --git a/pkg/message/manager_test.go b/pkg/message/manager_test.go
index 9f19ad2..07f9b29 100644
--- a/pkg/message/manager_test.go
+++ b/pkg/message/manager_test.go
@@ -392,7 +392,7 @@ func TestMarkSeen(t *testing.T) {
 	assert.False(t, msg.Seen, "msg should be unseen")
 
 	err = sm.MarkSeen("box1", id)
-	assert.NoError(t, err, "MarkSeen should succeed")
+	require.NoError(t, err, "MarkSeen should succeed")
 
 	// Verify test message seen.
 	msg, err = sm.GetMessage("box1", id)
@@ -414,7 +414,7 @@ func TestRemoveMessage(t *testing.T) {
 
 	// Delete message 2 and verify.
 	err = sm.RemoveMessage("box1", id2)
-	assert.NoError(t, err)
+	require.NoError(t, err)
 	got, err = sm.GetMetadata("box1")
 	require.NoError(t, err)
 	require.Len(t, got, 2, "Should be 2 messages remaining")
@@ -440,10 +440,10 @@ func TestPurgeMessages(t *testing.T) {
 
 	// Purge and verify.
 	err = sm.PurgeMessages("box1")
-	assert.NoError(t, err)
+	require.NoError(t, err)
 	got, err = sm.GetMetadata("box1")
 	require.NoError(t, err)
-	require.Len(t, got, 0, "Purge should remove all mailbox messages")
+	assert.Empty(t, got, "Purge should remove all mailbox messages")
 }
 
 func TestSourceReader(t *testing.T) {
@@ -543,7 +543,7 @@ func assertMessageCount(t *testing.T, sm *message.StoreManager, mailbox string,
 	t.Helper()
 
 	metas, err := sm.GetMetadata(mailbox)
-	assert.NoError(t, err, "StoreManager GetMetadata failed")
+	require.NoError(t, err, "StoreManager GetMetadata failed")
 
 	got := len(metas)
 	if got != count {
diff --git a/pkg/server/smtp/handler_test.go b/pkg/server/smtp/handler_test.go
index 7aa790d..550fad0 100644
--- a/pkg/server/smtp/handler_test.go
+++ b/pkg/server/smtp/handler_test.go
@@ -435,11 +435,12 @@ Hi!
 
 // playSession creates a new session, reads the greeting and then plays the script
 func playSession(t *testing.T, server *Server, script []scriptStep) error {
+	t.Helper()
 	pipe := setupSMTPSession(t, server)
 	c := textproto.NewConn(pipe)
 
 	if code, _, err := c.ReadCodeLine(220); err != nil {
-		return fmt.Errorf("Expected a 220 greeting, got %v", code)
+		return fmt.Errorf("expected a 220 greeting, got %v", code)
 	}
 
 	err := playScriptAgainst(t, c, script)
@@ -596,6 +597,7 @@ func setupSMTPServer(ds storage.Store, extHost *extension.Host) *Server {
 var sessionNum int
 
 func setupSMTPSession(t *testing.T, server *Server) net.Conn {
+	t.Helper()
 	logger := zerolog.New(zerolog.NewTestWriter(t))
 	serverConn, clientConn := net.Pipe()
 
diff --git a/pkg/storage/file/fstore_test.go b/pkg/storage/file/fstore_test.go
index 794c534..d471869 100644
--- a/pkg/storage/file/fstore_test.go
+++ b/pkg/storage/file/fstore_test.go
@@ -38,7 +38,7 @@ func TestSuite(t *testing.T) {
 func TestFSNew(t *testing.T) {
 	// Should fail if no path specified.
 	ds, err := New(config.Storage{}, extension.NewHost())
-	assert.ErrorContains(t, err, "parameter not specified")
+	require.ErrorContains(t, err, "parameter not specified")
 	assert.Nil(t, ds)
 }
 
@@ -100,7 +100,7 @@ func TestFSDirStructure(t *testing.T) {
 
 	// Delete message
 	err := ds.RemoveMessage(mbName, id1)
-	assert.Nil(t, err)
+	require.NoError(t, err)
 
 	// Message should be removed
 	expect = filepath.Join(mbPath, id1+".raw")
@@ -110,7 +110,7 @@ func TestFSDirStructure(t *testing.T) {
 
 	// Delete message
 	err = ds.RemoveMessage(mbName, id2)
-	assert.Nil(t, err)
+	require.NoError(t, err)
 
 	// Message should be removed
 	expect = filepath.Join(mbPath, id2+".raw")
@@ -147,15 +147,15 @@ func TestFSMissing(t *testing.T) {
 
 	// Delete a message file without removing it from index
 	msg, err := ds.GetMessage(mbName, sentIds[1])
-	assert.Nil(t, err)
+	require.NoError(t, err)
 	fmsg := msg.(*Message)
 	_ = os.Remove(fmsg.rawPath())
 	msg, err = ds.GetMessage(mbName, sentIds[1])
-	assert.Nil(t, err)
+	require.NoError(t, err)
 
 	// Try to read parts of message
 	_, err = msg.Source()
-	assert.Error(t, err)
+	require.Error(t, err)
 
 	if t.Failed() {
 		// Wait for handler to finish logging
@@ -176,7 +176,7 @@ func TestGetLatestMessage(t *testing.T) {
 	// Test empty mailbox
 	msg, err := ds.GetMessage(mbName, "latest")
 	assert.Nil(t, msg)
-	assert.Error(t, err)
+	require.Error(t, err)
 
 	// Deliver test message
 	deliverMessage(ds, mbName, "test", time.Now())
@@ -187,18 +187,18 @@ func TestGetLatestMessage(t *testing.T) {
 	// Test get the latest message
 	msg, err = ds.GetMessage(mbName, "latest")
 	require.NoError(t, err)
-	assert.True(t, msg.ID() == id2, "Expected %q to be equal to %q", msg.ID(), id2)
+	assert.Equal(t, id2, msg.ID(), "Expected %q to be equal to %q", msg.ID(), id2)
 
 	// Deliver test message 3
 	id3, _ := deliverMessage(ds, mbName, "test 3", time.Now())
 
 	msg, err = ds.GetMessage(mbName, "latest")
 	require.NoError(t, err)
-	assert.True(t, msg.ID() == id3, "Expected %q to be equal to %q", msg.ID(), id3)
+	assert.Equal(t, id3, msg.ID(), "Expected %q to be equal to %q", msg.ID(), id3)
 
 	// Test wrong id
 	_, err = ds.GetMessage(mbName, "wrongid")
-	assert.Error(t, err)
+	require.Error(t, err)
 
 	if t.Failed() {
 		// Wait for handler to finish logging
diff --git a/pkg/test/storage_suite.go b/pkg/test/storage_suite.go
index e0e1ba0..67178d6 100644
--- a/pkg/test/storage_suite.go
+++ b/pkg/test/storage_suite.go
@@ -157,7 +157,7 @@ func testContent(t *testing.T, store storage.Store, extHost *extension.Host) {
 	got, err := io.ReadAll(r)
 	require.NoError(t, err, "failed to read source")
 	err = r.Close()
-	assert.NoError(t, err, "failed to close source reader")
+	require.NoError(t, err, "failed to close source reader")
 
 	// Verify source.
 	if len(got) != len(content) {
@@ -425,10 +425,10 @@ func testVisitMailboxes(t *testing.T, ds storage.Store, extHost *extension.Host)
 			name = messages[0].Mailbox()
 		}
 
-		assert.Equal(t, 2, len(messages), "incorrect message count in mailbox %s", name)
+		assert.Len(t, messages, 2, "incorrect message count in mailbox %s", name)
 		return true
 	})
-	assert.NoError(t, err, "VisitMailboxes() failed")
+	require.NoError(t, err, "VisitMailboxes() failed")
 	assert.Equal(t, 5, nboxes, "visited %v mailboxes, want: 5", nboxes)
 }
 
diff --git a/pkg/test/storage_test.go b/pkg/test/storage_test.go
index 3f38288..c8c31a3 100644
--- a/pkg/test/storage_test.go
+++ b/pkg/test/storage_test.go
@@ -84,7 +84,7 @@ func TestStoreStubMailboxAddGetVisit(t *testing.T) {
 
 			want, ok := expectCounts[mailbox]
 			assert.True(t, ok, "Mailbox %q was unexpected", mailbox)
-			assert.Equal(t, want, len(m), "Unexpected message count for mailbox %q", mailbox)
+			assert.Len(t, m, want, "Unexpected message count for mailbox %q", mailbox)
 
 			delete(expectCounts, mailbox)
 
@@ -114,7 +114,7 @@ func TestStoreStubMarkSeen(t *testing.T) {
 	// Mark second message as seen.
 	seen := inputMsgs[1]
 	err := ss.MarkSeen("box1", seen.ID())
-	assert.NoError(t, err, "MarkSeen must not fail")
+	require.NoError(t, err, "MarkSeen must not fail")
 
 	// Verify message has seen flag.
 	got, err := ss.GetMessage("box1", seen.ID())
@@ -150,16 +150,16 @@ func TestStoreStubRemoveMessage(t *testing.T) {
 	// Delete second message.
 	deleted := inputMsgs[1]
 	err := ss.RemoveMessage("box1", deleted.ID())
-	assert.NoError(t, err, "DeleteMessage must not fail")
+	require.NoError(t, err, "DeleteMessage must not fail")
 
 	// Verify message is not in mailbox.
 	messages, err := ss.GetMessages("box1")
-	assert.NoError(t, err)
+	require.NoError(t, err)
 	assert.NotContains(t, messages, deleted, "Mailbox should not contain msg %q", deleted.ID())
 
 	// Verify message is no longer retrievable.
 	got, err := ss.GetMessage("box1", deleted.ID())
-	assert.Error(t, err)
+	require.Error(t, err)
 	assert.Nil(t, got, "Message should have been nil")
 
 	// Verify message is in deleted list.
@@ -181,12 +181,12 @@ func TestStoreStubPurgeMessages(t *testing.T) {
 
 	// Purge messages.
 	err := ss.PurgeMessages("box1")
-	assert.NoError(t, err, "PurgeMessages must not fail")
+	require.NoError(t, err, "PurgeMessages must not fail")
 
 	// Verify message is not in mailbox.
 	messages, err := ss.GetMessages("box1")
-	assert.NoError(t, err)
-	assert.Len(t, messages, 0, "Mailbox should be empty")
+	require.NoError(t, err)
+	assert.Empty(t, messages, "Mailbox should be empty")
 
 	// Verify messages are in deleted list.
 	for _, want := range inputMsgs {
@@ -208,15 +208,15 @@ func TestStoreStubForcedErrors(t *testing.T) {
 
 	// Verify methods return error.
 	_, err = ss.GetMessage("messageerr", id1)
-	assert.Error(t, err, "GetMessage()")
+	require.Error(t, err, "GetMessage()")
 	assert.NotEqual(t, storage.ErrNotExist, err)
 
 	_, err = ss.GetMessages("messageserr")
-	assert.Error(t, err, "GetMessages()")
+	require.Error(t, err, "GetMessages()")
 	assert.NotEqual(t, storage.ErrNotExist, err)
 
 	err = ss.MarkSeen("messageerr", id1)
-	assert.Error(t, err, "MarkSeen()")
+	require.Error(t, err, "MarkSeen()")
 	assert.NotEqual(t, storage.ErrNotExist, err)
 }