diff --git a/lightningd/Makefile b/lightningd/Makefile
index 466f24450..5143672d3 100644
--- a/lightningd/Makefile
+++ b/lightningd/Makefile
@@ -102,7 +102,8 @@ LIGHTNINGD_HEADERS_NOGEN =			\
 	$(CORE_HEADERS)				\
 	$(CORE_TX_HEADERS)			\
 	$(DAEMON_HEADERS)			\
-	$(WALLET_LIB_HEADERS)
+	$(WALLET_LIB_HEADERS)			\
+	lightningd/onchain/onchain_wire.h
 
 # Generated headers
 LIGHTNINGD_HEADERS_GEN =			\
diff --git a/lightningd/onchain/onchain_wire.c b/lightningd/onchain/onchain_wire.c
new file mode 100644
index 000000000..3a895bd0e
--- /dev/null
+++ b/lightningd/onchain/onchain_wire.c
@@ -0,0 +1,19 @@
+#include <ccan/structeq/structeq.h>
+#include <lightningd/htlc_wire.h>
+#include <lightningd/onchain/onchain_wire.h>
+#include <wire/wire.h>
+
+void towire_htlc_stub(u8 **pptr, const struct htlc_stub *htlc_stub)
+{
+	towire_side(pptr, htlc_stub->owner);
+	towire_u32(pptr, htlc_stub->cltv_expiry);
+	towire_ripemd160(pptr, &htlc_stub->ripemd);
+}
+
+void fromwire_htlc_stub(const u8 **cursor, size_t *max,
+			struct htlc_stub *htlc_stub)
+{
+	htlc_stub->owner = fromwire_side(cursor, max);
+	htlc_stub->cltv_expiry = fromwire_u32(cursor, max);
+	fromwire_ripemd160(cursor, max, &htlc_stub->ripemd);
+}
diff --git a/lightningd/onchain/onchain_wire.h b/lightningd/onchain/onchain_wire.h
new file mode 100644
index 000000000..0a3d89dcb
--- /dev/null
+++ b/lightningd/onchain/onchain_wire.h
@@ -0,0 +1,18 @@
+#ifndef LIGHTNING_LIGHTNINGD_ONCHAIN_WIRE_H
+#define LIGHTNING_LIGHTNINGD_ONCHAIN_WIRE_H
+#include "config.h"
+#include <ccan/short_types/short_types.h>
+#include <ccan/tal/tal.h>
+#include <daemon/htlc.h>
+
+/* The minimal info about an htlc. */
+struct htlc_stub {
+	enum side owner;
+	u32 cltv_expiry;
+	struct ripemd160 ripemd;
+};
+
+void towire_htlc_stub(u8 **pptr, const struct htlc_stub *htlc_stub);
+void fromwire_htlc_stub(const u8 **cursor, size_t *max,
+			struct htlc_stub *htlc_stub);
+#endif /* LIGHTNING_LIGHTNINGD_ONCHAIN_WIRE_H */