diff --git a/channeld/Makefile b/channeld/Makefile
index 1c15d2ef8040..d68f6a18fa6e 100644
--- a/channeld/Makefile
+++ b/channeld/Makefile
@@ -72,6 +72,7 @@ CHANNELD_COMMON_OBJS :=				\
 	common/wire_error.o			\
 	common/wireaddr.o			\
 	gossipd/gen_gossip_wire.o		\
+	hsmd/gen_hsm_client_wire.o		\
 	lightningd/gossip_msg.o			\
 	wire/fromwire.o				\
 	wire/towire.o
diff --git a/closingd/Makefile b/closingd/Makefile
index 0eedf7af8ade..32279bbd46cb 100644
--- a/closingd/Makefile
+++ b/closingd/Makefile
@@ -72,6 +72,7 @@ CLOSINGD_COMMON_OBJS :=				\
 	common/wire_error.o			\
 	common/wireaddr.o			\
 	gossipd/gen_gossip_wire.o		\
+	hsmd/gen_hsm_client_wire.o		\
 	lightningd/gossip_msg.o
 
 closingd/gen_closing_wire.h: $(WIRE_GEN) closingd/closing_wire.csv
diff --git a/connectd/Makefile b/connectd/Makefile
index f32dc7bce597..d3eacb9bb80e 100644
--- a/connectd/Makefile
+++ b/connectd/Makefile
@@ -61,7 +61,6 @@ CONNECTD_COMMON_OBJS :=				\
 	common/wireaddr.o			\
 	common/wire_error.o			\
 	gossipd/gen_gossip_wire.o		\
-	hsmd/client.o				\
 	hsmd/gen_hsm_client_wire.o		\
 	lightningd/gossip_msg.o			\
 	wire/gen_onion_wire.o
diff --git a/connectd/connectd.c b/connectd/connectd.c
index 192dae73a17a..fc97bab8b85a 100644
--- a/connectd/connectd.c
+++ b/connectd/connectd.c
@@ -39,7 +39,6 @@
 #include <connectd/tor_autoservice.h>
 #include <errno.h>
 #include <gossipd/gen_gossip_wire.h>
-#include <hsmd/client.h>
 #include <hsmd/gen_hsm_client_wire.h>
 #include <inttypes.h>
 #include <lightningd/gossip_msg.h>
@@ -1286,6 +1285,21 @@ static struct io_plan *recv_req(struct io_conn *conn, struct daemon_conn *master
 		      t, tal_hex(tmpctx, master->msg_in));
 }
 
+/* Helper for handshake.c */
+bool hsm_do_ecdh(struct secret *ss, const struct pubkey *point)
+{
+	u8 *req = towire_hsm_ecdh_req(tmpctx, point), *resp;
+
+	if (!wire_sync_write(HSM_FD, req))
+		return false;
+	resp = wire_sync_read(req, HSM_FD);
+	if (!resp)
+		return false;
+	if (!fromwire_hsm_ecdh_resp(resp, ss))
+		return false;
+	return true;
+}
+
 #ifndef TESTING
 static void master_gone(struct io_conn *unused UNUSED, struct daemon_conn *dc UNUSED)
 {
@@ -1312,7 +1326,6 @@ int main(int argc, char *argv[])
 	daemon_conn_init(daemon, &daemon->master, STDIN_FILENO, recv_req,
 			 master_gone);
 	status_setup_async(&daemon->master);
-	hsm_setup(HSM_FD);
 
 	/* When conn closes, everything is freed. */
 	tal_steal(daemon->master.conn, daemon);
diff --git a/connectd/handshake.c b/connectd/handshake.c
index 296e0a4faf08..d861e2424c05 100644
--- a/connectd/handshake.c
+++ b/connectd/handshake.c
@@ -13,7 +13,6 @@
 #include <common/wireaddr.h>
 #include <connectd/handshake.h>
 #include <errno.h>
-#include <hsmd/client.h>
 #include <secp256k1.h>
 #include <secp256k1_ecdh.h>
 #include <sodium/crypto_aead_chacha20poly1305.h>
diff --git a/connectd/handshake.h b/connectd/handshake.h
index 2e501dd8f381..20c51ecb9b44 100644
--- a/connectd/handshake.h
+++ b/connectd/handshake.h
@@ -51,4 +51,6 @@ struct io_plan *responder_handshake_(struct io_conn *conn,
 							   void *cbarg),
 				     void *cbarg);
 
+/* helper which is defined in connect.c */
+bool hsm_do_ecdh(struct secret *ss, const struct pubkey *point);
 #endif /* LIGHTNING_CONNECTD_HANDSHAKE_H */
diff --git a/gossipd/Makefile b/gossipd/Makefile
index 264fe33aee93..cdb1e122cedb 100644
--- a/gossipd/Makefile
+++ b/gossipd/Makefile
@@ -61,7 +61,6 @@ GOSSIPD_COMMON_OBJS :=				\
 	common/wireaddr.o			\
 	common/wire_error.o			\
 	connectd/gen_connect_gossip_wire.o	\
-	hsmd/client.o				\
 	hsmd/gen_hsm_client_wire.o		\
 	lightningd/gossip_msg.o			\
 	wire/gen_onion_wire.o
diff --git a/gossipd/gossipd.c b/gossipd/gossipd.c
index 45c00be6a4c9..a05025303a44 100644
--- a/gossipd/gossipd.c
+++ b/gossipd/gossipd.c
@@ -36,7 +36,6 @@
 #include <gossipd/broadcast.h>
 #include <gossipd/gen_gossip_wire.h>
 #include <gossipd/routing.h>
-#include <hsmd/client.h>
 #include <hsmd/gen_hsm_client_wire.h>
 #include <inttypes.h>
 #include <lightningd/gossip_msg.h>
@@ -2258,7 +2257,6 @@ int main(int argc, char *argv[])
 	daemon_conn_init(daemon, &daemon->master, STDIN_FILENO, recv_req,
 			 master_gone);
 	status_setup_async(&daemon->master);
-	hsm_setup(HSM_FD);
 	daemon_conn_init(daemon, &daemon->connectd, CONNECTD_FD, connectd_req,
 			 NULL);
 
diff --git a/hsmd/Makefile b/hsmd/Makefile
index 5147f21f3dc4..dbc5a17c95aa 100644
--- a/hsmd/Makefile
+++ b/hsmd/Makefile
@@ -6,16 +6,9 @@ hsmd-wrongdir:
 
 default: hsmd-all
 
-# Clients use this:
-LIGHTNINGD_HSM_CLIENT_HEADERS := hsmd/client.h
-LIGHTNINGD_HSM_CLIENT_SRC := hsmd/client.c hsmd/gen_hsm_client_wire.c
-LIGHTNINGD_HSM_CLIENT_OBJS := $(LIGHTNINGD_HSM_CLIENT_SRC:.c=.o)
-
-# lightningd/hsm needs these:
-LIGHTNINGD_HSM_HEADERS := hsmd/gen_hsm_client_wire.h
-
 LIGHTNINGD_HSM_SRC := hsmd/hsmd.c	\
-	$(LIGHTNINGD_HSM_HEADERS:.h=.c)
+	hsmd/gen_hsm_client_wire.c
+LIGHTNINGD_HSM_HEADERS := hsmd/gen_hsm_client_wire.h
 LIGHTNINGD_HSM_OBJS := $(LIGHTNINGD_HSM_SRC:.c=.o)
 
 # Common source we use.
@@ -40,20 +33,17 @@ HSMD_COMMON_OBJS :=				\
 	common/withdraw_tx.o
 
 # For checking
-LIGHTNINGD_HSM_ALLSRC_NOGEN := $(filter-out hsmd/gen_%, $(LIGHTNINGD_HSM_CLIENT_SRC) $(LIGHTNINGD_HSM_SRC))
-LIGHTNINGD_HSM_ALLHEADERS_NOGEN := $(filter-out hsmd/gen_%, $(LIGHTNINGD_HSM_CLIENT_HEADERS) $(LIGHTNINGD_HSM_HEADERS))
-
-# Add to headers which any object might need.
-LIGHTNINGD_HEADERS_GEN += $(LIGHTNINGD_HSM_HEADERS) $(LIGHTNINGD_HSM_CLIENT_HEADERS)
+LIGHTNINGD_HSM_ALLSRC_NOGEN := $(filter-out hsmd/gen_%, $(LIGHTNINGD_HSM_SRC) $(LIGHTNINGD_HSM_SRC))
+LIGHTNINGD_HSM_ALLHEADERS_NOGEN := $(filter-out hsmd/gen_%, $(LIGHTNINGD_HSM_HEADERS))
 
-$(LIGHTNINGD_HSM_OBJS) $(LIGHTNINGD_HSM_CLIENT_OBJS): $(LIGHTNINGD_HEADERS)
+$(LIGHTNINGD_HSM_OBJS): $(LIGHTNINGD_HEADERS)
 
 # Make sure these depend on everything.
-ALL_OBJS += $(LIGHTNINGD_HSM_OBJS) $(LIGHTNINGD_HSM_CLIENT_OBJS)
+ALL_OBJS += $(LIGHTNINGD_HSM_OBJS)
 ALL_PROGRAMS += lightningd/lightning_hsmd
-ALL_GEN_HEADERS += $(LIGHTNINGD_HSM_HEADERS)
+ALL_GEN_HEADERS += hsmd/gen_hsm_client_wire.h
 
-hsmd-all: lightningd/lightning_hsmd $(LIGHTNINGD_HSM_CLIENT_OBJS)
+hsmd-all: lightningd/lightning_hsmd
 
 lightningd/lightning_hsmd: $(LIGHTNINGD_HSM_OBJS) $(LIGHTNINGD_LIB_OBJS) $(HSMD_COMMON_OBJS) $(BITCOIN_OBJS) $(WIRE_OBJS)
 
@@ -70,7 +60,7 @@ hsmd/gen_hsm_wire.c: $(WIRE_GEN) hsmd/hsm_wire.csv
 	$(WIRE_GEN) ${@:.c=.h} hsm_wire_type < hsmd/hsm_wire.csv > $@
 
 check-source: $(LIGHTNINGD_HSM_ALLSRC_NOGEN:%=check-src-include-order/%) $(LIGHTNINGD_HSM_ALLHEADERS_NOGEN:%=check-hdr-include-order/%)
-check-source-bolt: $(LIGHTNINGD_HSM_SRC:%=bolt-check/%) $(LIGHTNINGD_HSM_HEADERS:%=bolt-check/%)
+check-source-bolt: $(LIGHTNINGD_HSM_SRC:%=bolt-check/%)
 
 check-whitespace: $(LIGHTNINGD_HSM_ALLSRC_NOGEN:%=check-whitespace/%) $(LIGHTNINGD_HSM_ALLHEADERS_NOGEN:%=check-whitespace/%)
 
diff --git a/hsmd/client.c b/hsmd/client.c
deleted file mode 100644
index c631f826fe73..000000000000
--- a/hsmd/client.c
+++ /dev/null
@@ -1,29 +0,0 @@
-#include <hsmd/client.h>
-#include <hsmd/gen_hsm_client_wire.h>
-#include <wire/wire_sync.h>
-
-static int hsm_fd = -1;
-
-void hsm_setup(int fd)
-{
-	hsm_fd = fd;
-}
-
-bool hsm_do_ecdh(struct secret *ss, const struct pubkey *point)
-{
-	u8 *req = towire_hsm_ecdh_req(NULL, point), *resp;
-
-	if (!wire_sync_write(hsm_fd, req))
-		goto fail;
-	resp = wire_sync_read(req, hsm_fd);
-	if (!resp)
-		goto fail;
-	if (!fromwire_hsm_ecdh_resp(resp, ss))
-		goto fail;
-	tal_free(req);
-	return true;
-
-fail:
-	tal_free(req);
-	return false;
-}
diff --git a/hsmd/client.h b/hsmd/client.h
deleted file mode 100644
index 9adfb28fbf49..000000000000
--- a/hsmd/client.h
+++ /dev/null
@@ -1,17 +0,0 @@
-/* API to ask the HSM for things. */
-#ifndef LIGHTNING_HSMD_CLIENT_H
-#define LIGHTNING_HSMD_CLIENT_H
-#include "config.h"
-#include <ccan/endian/endian.h>
-#include <ccan/short_types/short_types.h>
-#include <stdbool.h>
-
-struct pubkey;
-struct secret;
-
-/* Setup communication to the HSM */
-void hsm_setup(int fd);
-
-/* Do ECDH using this node id secret. */
-bool hsm_do_ecdh(struct secret *ss, const struct pubkey *point);
-#endif /* LIGHTNING_HSMD_CLIENT_H */
diff --git a/hsmd/hsmd.c b/hsmd/hsmd.c
index 9acb0edb521c..3b187536da3f 100644
--- a/hsmd/hsmd.c
+++ b/hsmd/hsmd.c
@@ -31,7 +31,6 @@
 #include <errno.h>
 #include <fcntl.h>
 #include <hsmd/capabilities.h>
-#include <hsmd/client.h>
 #include <hsmd/gen_hsm_client_wire.h>
 #include <inttypes.h>
 #include <secp256k1_ecdh.h>
diff --git a/lightningd/Makefile b/lightningd/Makefile
index 682fe33a724f..9508dfe62ce2 100644
--- a/lightningd/Makefile
+++ b/lightningd/Makefile
@@ -48,7 +48,8 @@ LIGHTNINGD_COMMON_OBJS :=			\
 	common/wallet_tx.o			\
 	common/wire_error.o			\
 	common/wireaddr.o			\
-	common/withdraw_tx.o
+	common/withdraw_tx.o			\
+	hsmd/gen_hsm_client_wire.o
 
 LIGHTNINGD_SRC :=				\
 	lightningd/bitcoind.c			\
@@ -120,7 +121,7 @@ check-makefile: check-lightningd-makefile
 check-lightningd-makefile:
 	@for f in lightningd/*.h lightningd/*/*.h; do if ! echo $(LIGHTNINGD_HEADERS_NOGEN) $(LIGHTNINGD_HEADERS_GEN) "" | grep -q "$$f "; then echo $$f not mentioned in LIGHTNINGD_HEADERS_NOGEN or LIGHTNINGD_HEADERS_GEN >&2; exit 1; fi; done
 
-lightningd/lightningd: $(LIGHTNINGD_OBJS) $(LIGHTNINGD_COMMON_OBJS) $(BITCOIN_OBJS) $(WIRE_OBJS) $(WIRE_ONION_OBJS) $(LIGHTNINGD_HSM_CLIENT_OBJS) $(LIGHTNINGD_HANDSHAKE_CONTROL_OBJS) $(LIGHTNINGD_GOSSIP_CONTROL_OBJS) $(LIGHTNINGD_OPENING_CONTROL_OBJS) $(LIGHTNINGD_CHANNEL_CONTROL_OBJS) $(LIGHTNINGD_CLOSING_CONTROL_OBJS) $(LIGHTNINGD_ONCHAIN_CONTROL_OBJS) $(WALLET_LIB_OBJS) $(LIGHTNINGD_CONNECT_CONTROL_OBJS) 
+lightningd/lightningd: $(LIGHTNINGD_OBJS) $(LIGHTNINGD_COMMON_OBJS) $(BITCOIN_OBJS) $(WIRE_OBJS) $(WIRE_ONION_OBJS) $(LIGHTNINGD_HANDSHAKE_CONTROL_OBJS) $(LIGHTNINGD_GOSSIP_CONTROL_OBJS) $(LIGHTNINGD_OPENING_CONTROL_OBJS) $(LIGHTNINGD_CHANNEL_CONTROL_OBJS) $(LIGHTNINGD_CLOSING_CONTROL_OBJS) $(LIGHTNINGD_ONCHAIN_CONTROL_OBJS) $(WALLET_LIB_OBJS) $(LIGHTNINGD_CONNECT_CONTROL_OBJS) 
 
 clean: lightningd-clean
 
diff --git a/onchaind/Makefile b/onchaind/Makefile
index 1ea8b7bbcaf5..e2d76695be33 100644
--- a/onchaind/Makefile
+++ b/onchaind/Makefile
@@ -68,7 +68,8 @@ ONCHAIND_COMMON_OBJS :=				\
 	common/type_to_string.o			\
 	common/utils.o				\
 	common/utxo.o				\
-	common/version.o
+	common/version.o			\
+	hsmd/gen_hsm_client_wire.o
 
 onchaind/gen_onchain_wire.h: $(WIRE_GEN) onchaind/onchain_wire.csv
 	$(WIRE_GEN) --header $@ onchain_wire_type < onchaind/onchain_wire.csv > $@
diff --git a/openingd/Makefile b/openingd/Makefile
index 92fb90a0ac67..33cbea1c040a 100644
--- a/openingd/Makefile
+++ b/openingd/Makefile
@@ -70,6 +70,7 @@ OPENINGD_COMMON_OBJS :=				\
 	common/wire_error.o			\
 	common/wireaddr.o			\
 	gossipd/gen_gossip_wire.o		\
+	hsmd/gen_hsm_client_wire.o		\
 	lightningd/gossip_msg.o
 
 $(LIGHTNINGD_OPENING_OBJS): $(LIGHTNINGD_HEADERS)