diff --git a/Makefile b/Makefile
index a02b212..7d28ab5 100644
--- a/Makefile
+++ b/Makefile
@@ -42,5 +42,9 @@ cpptests:
 	@LD_LIBRARY_PATH=./target/release/ ./cpp_test
 	@rm cpp_test
 
+gotests:
+	cargo +nightly build --release
+	go test go/libbolt.go go/libbolt_test.go
+
 clean:
 	cargo +nightly clean
diff --git a/go/libbolt.go b/go/libbolt.go
index cc86c97..bd113fc 100644
--- a/go/libbolt.go
+++ b/go/libbolt.go
@@ -18,6 +18,7 @@ type setupResp struct {
 	ComProof      string `json:"com_proof"`
 	IsTokenValid  bool   `json:"is_token_valid,string"`
 	IsEstablished bool   `json:"is_established,string"`
+	IsPayValid    bool   `json:"is_pay_valid,string"`
 	Payment       string `json:"payment"`
 	CloseToken    string `json:"close_token"`
 	RevokeToken   string `json:"revoke_token"`
@@ -104,7 +105,7 @@ func BidirectionalPayVerifyRevokeToken(serRevokeToken string, serMerchState stri
 func BidirectionalPayVerifyPaymentToken(serChannelState string, serCustState string, serPayToken string) (string, bool) {
 	resp := C.GoString(C.ffishim_bidirectional_pay_verify_payment_token(C.CString(serChannelState), C.CString(serCustState), C.CString(serPayToken)))
 	r := processCResponse(resp)
-	return r.CustState, r.IsTokenValid
+	return r.CustState, r.IsPayValid
 }
 
 func BidirectionalCustomerClose(serChannelState string, serCustState string) string {
diff --git a/go/libbolt_test.go b/go/libbolt_test.go
index 0a740c9..2b70723 100644
--- a/go/libbolt_test.go
+++ b/go/libbolt_test.go
@@ -41,3 +41,42 @@ func Test_Establish(t *testing.T) {
 	assert.True(t, isChannelEstablished)
 }
 
+func Test_Pay(t *testing.T) {
+	b0Cust := 1000
+	b0Merch := 100
+	channelState, channelToken, merchState, custState := setup(b0Cust, b0Merch)
+	channelToken, custState, com, comProof := BidirectionalEstablishCustomerGenerateProof(channelToken, custState)
+	closeToken := BidirectionalEstablishMerchantIssueCloseToken(channelState, com, comProof, b0Cust, b0Merch, merchState)
+	_, channelState, custState = BidirectionalVerifyCloseToken(channelState, custState, closeToken)
+	payToken := BidirectionalEstablishMerchantIssuePayToken(channelState, com, merchState)
+	_, channelState, custState = BidirectionalEstablishCustomerFinal(channelState, custState, payToken)
+
+	payment, newCustState := BidirectionalPayGeneratePaymentProof(channelState, custState, 10)
+	closeToken, merchState = BidirectionalPayVerifyPaymentProof(channelState, payment, merchState)
+	revokeToken, custState := BidirectionalPayGenerateRevokeToken(channelState, custState, newCustState, closeToken)
+	payToken, merchState = BidirectionalPayVerifyRevokeToken(revokeToken, merchState)
+	custState, isTokenValid := BidirectionalPayVerifyPaymentToken(channelState, custState, payToken)
+	assert.True(t, isTokenValid)
+}
+
+func Test_Close(t *testing.T) {
+	b0Cust := 1000
+	b0Merch := 100
+	channelState, channelToken, merchState, custState := setup(b0Cust, b0Merch)
+	channelToken, custState, com, comProof := BidirectionalEstablishCustomerGenerateProof(channelToken, custState)
+	closeToken := BidirectionalEstablishMerchantIssueCloseToken(channelState, com, comProof, b0Cust, b0Merch, merchState)
+	_, channelState, custState = BidirectionalVerifyCloseToken(channelState, custState, closeToken)
+	payToken := BidirectionalEstablishMerchantIssuePayToken(channelState, com, merchState)
+	_, channelState, custState = BidirectionalEstablishCustomerFinal(channelState, custState, payToken)
+
+	payment, newCustState := BidirectionalPayGeneratePaymentProof(channelState, custState, 10)
+	closeToken, merchState = BidirectionalPayVerifyPaymentProof(channelState, payment, merchState)
+	revokeToken, custState := BidirectionalPayGenerateRevokeToken(channelState, custState, newCustState, closeToken)
+	payToken, merchState = BidirectionalPayVerifyRevokeToken(revokeToken, merchState)
+	custState, _ = BidirectionalPayVerifyPaymentToken(channelState, custState, payToken)
+
+	custClose := BidirectionalCustomerClose(channelState, custState)
+	_, _, err := BidirectionalMerchantClose(channelState, channelToken, "onChainAddress", custClose, merchState)
+	assert.Equal(t, "merchant_close - Could not find entry for wpk & revoke token pair. Valid close!", err)
+}
+
diff --git a/src/ffishim.rs b/src/ffishim.rs
index d7adb09..3cf9125 100644
--- a/src/ffishim.rs
+++ b/src/ffishim.rs
@@ -15,7 +15,7 @@ pub mod ffishim {
     use std::alloc::handle_alloc_error;
 
     fn error_message(s: String) -> *mut c_char {
-        let ser = ["{\'error\':", serde_json::to_string(&s).unwrap().as_str(), "}"].concat();
+        let ser = ["{\'error\':\'", &s, "\'}"].concat();
         let cser = CString::new(ser).unwrap();
         cser.into_raw()
     }