diff --git a/gdb/mgodb/bson.go b/gdb/mgodb/bson.go
index ec8ea50..8ee130d 100644
--- a/gdb/mgodb/bson.go
+++ b/gdb/mgodb/bson.go
@@ -7,7 +7,10 @@
 
 package mgodb
 
-import "go.mongodb.org/mongo-driver/bson"
+import (
+	"go.mongodb.org/mongo-driver/bson"
+	"go.mongodb.org/mongo-driver/bson/primitive"
+)
 
 // M is an unordered representation of a BSON document.
 // bson.M{"foo": "bar", "hello": "world", "pi": 3.14159}
@@ -20,3 +23,5 @@ type D = bson.D
 // An A is an ordered representation of a BSON array.
 // bson.A{"bar", "world", 3.14159, bson.D{{"qux", 12345}}}
 type A = bson.A
+
+type ObjectId = primitive.ObjectID