diff --git a/sqlite3_test.go b/sqlite3_test.go
index eb9d18e..8efb409 100644
--- a/sqlite3_test.go
+++ b/sqlite3_test.go
@@ -1184,66 +1184,6 @@ func TestFunctionRegistration(t *testing.T) {
 	}
 }
 
-type sumAggregator int64
-
-func (s *sumAggregator) Step(x int64) {
-	*s += sumAggregator(x)
-}
-
-func (s *sumAggregator) Done() int64 {
-	return int64(*s)
-}
-
-func TestAggregatorRegistration(t *testing.T) {
-	customSum := func() *sumAggregator {
-		var ret sumAggregator
-		return &ret
-	}
-
-	sql.Register("sqlite3_AggregatorRegistration", &SQLiteDriver{
-		ConnectHook: func(conn *SQLiteConn) error {
-			if err := conn.RegisterAggregator("customSum", customSum, true); err != nil {
-				return err
-			}
-			return nil
-		},
-	})
-	db, err := sql.Open("sqlite3_AggregatorRegistration", ":memory:")
-	if err != nil {
-		t.Fatal("Failed to open database:", err)
-	}
-	defer db.Close()
-
-	_, err = db.Exec("create table foo (department integer, profits integer)")
-	if err != nil {
-		// trace feature is not implemented
-		t.Skip("Failed to create table:", err)
-	}
-
-	_, err = db.Exec("insert into foo values (1, 10), (1, 20), (2, 42)")
-	if err != nil {
-		t.Fatal("Failed to insert records:", err)
-	}
-
-	tests := []struct {
-		dept, sum int64
-	}{
-		{1, 30},
-		{2, 42},
-	}
-
-	for _, test := range tests {
-		var ret int64
-		err = db.QueryRow("select customSum(profits) from foo where department = $1 group by department", test.dept).Scan(&ret)
-		if err != nil {
-			t.Fatal("Query failed:", err)
-		}
-		if ret != test.sum {
-			t.Fatalf("Custom sum returned wrong value, got %d, want %d", ret, test.sum)
-		}
-	}
-}
-
 func TestDeclTypes(t *testing.T) {
 
 	d := SQLiteDriver{}
diff --git a/sqlite3_trace_test.go b/sqlite3_trace_test.go
new file mode 100644
index 0000000..57a6757
--- /dev/null
+++ b/sqlite3_trace_test.go
@@ -0,0 +1,72 @@
+// Copyright (C) 2016 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+// +build trace
+
+package sqlite3
+
+import (
+	"database/sql"
+	"testing"
+)
+
+type sumAggregator int64
+
+func (s *sumAggregator) Step(x int64) {
+	*s += sumAggregator(x)
+}
+
+func (s *sumAggregator) Done() int64 {
+	return int64(*s)
+}
+
+func TestAggregatorRegistration(t *testing.T) {
+	customSum := func() *sumAggregator {
+		var ret sumAggregator
+		return &ret
+	}
+
+	sql.Register("sqlite3_AggregatorRegistration", &SQLiteDriver{
+		ConnectHook: func(conn *SQLiteConn) error {
+			if err := conn.RegisterAggregator("customSum", customSum, true); err != nil {
+				return err
+			}
+			return nil
+		},
+	})
+	db, err := sql.Open("sqlite3_AggregatorRegistration", ":memory:")
+	if err != nil {
+		t.Fatal("Failed to open database:", err)
+	}
+	defer db.Close()
+
+	_, err = db.Exec("create table foo (department integer, profits integer)")
+	if err != nil {
+		// trace feature is not implemented
+		t.Skip("Failed to create table:", err)
+	}
+
+	_, err = db.Exec("insert into foo values (1, 10), (1, 20), (2, 42)")
+	if err != nil {
+		t.Fatal("Failed to insert records:", err)
+	}
+
+	tests := []struct {
+		dept, sum int64
+	}{
+		{1, 30},
+		{2, 42},
+	}
+
+	for _, test := range tests {
+		var ret int64
+		err = db.QueryRow("select customSum(profits) from foo where department = $1 group by department", test.dept).Scan(&ret)
+		if err != nil {
+			t.Fatal("Query failed:", err)
+		}
+		if ret != test.sum {
+			t.Fatalf("Custom sum returned wrong value, got %d, want %d", ret, test.sum)
+		}
+	}
+}
diff --git a/tracecallback.go b/tracecallback.go
index 93688d4..de1d504 100644
--- a/tracecallback.go
+++ b/tracecallback.go
@@ -1,5 +1,4 @@
 // Copyright (C) 2016 Yasuhiro Matsumoto <mattn.jp@gmail.com>.
-// TODO: add "Gimpl do foo" team?
 //
 // Use of this source code is governed by an MIT-style
 // license that can be found in the LICENSE file.