diff --git a/db/model/callback_type.go b/db/model/callback_type.go
new file mode 100644
index 0000000..42ff608
--- /dev/null
+++ b/db/model/callback_type.go
@@ -0,0 +1,29 @@
+package model
+
+type CallbackType uint8
+
+const (
+	GET CallbackType = iota
+	PRE_UPDATE
+	POST_UPDATE
+	PRE_ADD
+	POST_ADD
+	PRE_REMOVE
+	POST_REMOVE
+	POST_LISTCHANGE
+)
+
+var enumCallbackTypes = []string{
+	"GET",
+	"PRE_UPDATE",
+	"POST_UPDATE",
+	"PRE_ADD",
+	"POST_ADD",
+	"PRE_REMOVE",
+	"POST_REMOVE",
+	"POST_LISTCHANGE",
+}
+
+func (t CallbackType) String() string {
+	return enumCallbackTypes[t]
+}