diff --git a/mock/service.go b/mock/service.go
new file mode 100644
index 0000000..8c9e555
--- /dev/null
+++ b/mock/service.go
@@ -0,0 +1,42 @@
+package mock
+
+import (
+	"github.com/gin-gonic/gin"
+	"github.com/google/uuid"
+	"payment-poc/database"
+	"payment-poc/state"
+)
+
+type Service struct {
+	BackendUrl string
+}
+
+func (s Service) UpdatePayment(entry database.PaymentEntry) (updatedEntry database.PaymentEntry, err error) {
+	return entry, nil
+}
+
+func (s Service) CreatePaymentUrl(entry database.PaymentEntry) (updateEntry database.PaymentEntry, url string, err error) {
+	return entry, "/mock/gateway/" + entry.Id.String(), nil
+}
+
+func (s Service) CompleteTransaction(entry database.PaymentEntry, amount int64) (database.PaymentEntry, error) {
+	entry.Amount = &amount
+	entry.State = state.StateCompleted
+	return entry, nil
+}
+
+func (s Service) CancelTransaction(entry database.PaymentEntry) (database.PaymentEntry, error) {
+	entry.State = state.StateVoided
+	return entry, nil
+}
+
+func (s Service) HandleResponse(c *gin.Context, provider *database.PaymentEntryProvider, paymentState state.PaymentState) (string, error) {
+	id := uuid.MustParse(c.Query("id"))
+	entry, err := provider.FetchById(id)
+	if err != nil {
+		return "", err
+	}
+	entry.State = paymentState
+	_, err = provider.UpdateEntry(entry)
+	return "/entries/" + id.String(), err
+}