diff --git a/bfdd/bfdd_nb_config.c b/bfdd/bfdd_nb_config.c
index 50f953115c..48dcce3ddf 100644
--- a/bfdd/bfdd_nb_config.c
+++ b/bfdd/bfdd_nb_config.c
@@ -383,7 +383,7 @@ int bfdd_bfd_sessions_single_hop_administrative_down_modify(
 
 	bs = nb_running_get_entry(dnode, NULL, true);
 
-	if (shutdown == false) {
+	if (!shutdown) {
 		if (!BFD_CHECK_FLAG(bs->flags, BFD_SESS_FLAG_SHUTDOWN))
 			return NB_OK;
 
@@ -447,7 +447,7 @@ int bfdd_bfd_sessions_single_hop_echo_mode_modify(enum nb_event event,
 
 	bs = nb_running_get_entry(dnode, NULL, true);
 
-	if (echo == false) {
+	if (!echo) {
 		if (!BFD_CHECK_FLAG(bs->flags, BFD_SESS_FLAG_ECHO))
 			return NB_OK;
 
diff --git a/bfdd/bfdd_vty.c b/bfdd/bfdd_vty.c
index 3b795748c0..2a98b0fb02 100644
--- a/bfdd/bfdd_vty.c
+++ b/bfdd/bfdd_vty.c
@@ -500,7 +500,7 @@ static void _display_peers_brief(struct vty *vty, const char *vrfname, bool use_
 
 	bvt.vrfname = vrfname;
 
-	if (use_json == false) {
+	if (!use_json) {
 		bvt.vty = vty;
 
 		vty_out(vty, "Session count: %lu\n", bfd_get_session_count());
diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c
index 1cd0bbe578..996746bf82 100644
--- a/bgpd/bgp_route.c
+++ b/bgpd/bgp_route.c
@@ -299,7 +299,7 @@ static int bgp_node_set_defer_flag(struct bgp_node *rn, bool delete)
 {
 	struct peer *peer;
 	struct bgp_path_info *old_pi, *nextpi;
-	bool set_flag = 0;
+	bool set_flag = false;
 	struct bgp *bgp = NULL;
 	struct bgp_table *table = NULL;
 	afi_t afi = 0;
@@ -339,7 +339,7 @@ static int bgp_node_set_defer_flag(struct bgp_node *rn, bool delete)
 		 */
 		if (CHECK_FLAG(old_pi->flags, BGP_PATH_STALE)
 		    && (old_pi->sub_type == BGP_ROUTE_NORMAL)) {
-			set_flag = 1;
+			set_flag = true;
 		} else {
 			/* If the peer is graceful restart capable and peer is
 			 * restarting mode, set the flag BGP_NODE_SELECT_DEFER
@@ -349,7 +349,7 @@ static int bgp_node_set_defer_flag(struct bgp_node *rn, bool delete)
 			    && BGP_PEER_RESTARTING_MODE(peer)
 			    && (old_pi
 				&& old_pi->sub_type == BGP_ROUTE_NORMAL)) {
-				set_flag = 1;
+				set_flag = true;
 			}
 		}
 		if (set_flag)
diff --git a/bgpd/bgp_vty.c b/bgpd/bgp_vty.c
index 28e22b685d..29d3b3878a 100644
--- a/bgpd/bgp_vty.c
+++ b/bgpd/bgp_vty.c
@@ -9440,7 +9440,7 @@ static void bgp_show_neighnor_graceful_restart_rbit(struct vty *vty,
 						    bool use_json,
 						    json_object *json)
 {
-	bool rbit_status = 0;
+	bool rbit_status = false;
 
 	if (!use_json)
 		vty_out(vty, "\n    R bit: ");
@@ -9450,9 +9450,9 @@ static void bgp_show_neighnor_graceful_restart_rbit(struct vty *vty,
 	    && (p->status == Established)) {
 
 		if (CHECK_FLAG(p->cap, PEER_CAP_RESTART_BIT_RCV))
-			rbit_status = 1;
+			rbit_status = true;
 		else
-			rbit_status = 0;
+			rbit_status = false;
 	}
 
 	if (rbit_status) {
diff --git a/bgpd/bgpd.c b/bgpd/bgpd.c
index 96b307ee21..f28e557572 100644
--- a/bgpd/bgpd.c
+++ b/bgpd/bgpd.c
@@ -3148,7 +3148,7 @@ int bgp_handle_socket(struct bgp *bgp, struct vrf *vrf, vrf_id_t old_vrf_id,
 		/*
 		 * suppress vrf socket
 		 */
-		if (create == false) {
+		if (!create) {
 			bgp_close_vrf_socket(bgp);
 			return 0;
 		}
diff --git a/lib/frr_zmq.c b/lib/frr_zmq.c
index 7781beae5e..565936a410 100644
--- a/lib/frr_zmq.c
+++ b/lib/frr_zmq.c
@@ -177,7 +177,7 @@ int funcname_frrzmq_thread_add_read(struct thread_master *master,
 	else {
 		cb = XCALLOC(MTYPE_ZEROMQ_CB, sizeof(struct frrzmq_cb));
 
-		cb->write.cancelled = 1;
+		cb->write.cancelled = true;
 		*cbp = cb;
 	}
 
@@ -187,7 +187,7 @@ int funcname_frrzmq_thread_add_read(struct thread_master *master,
 	cb->read.cb_msg = msgfunc;
 	cb->read.cb_part = partfunc;
 	cb->read.cb_error = errfunc;
-	cb->read.cancelled = 0;
+	cb->read.cancelled = false;
 
 	if (events & ZMQ_POLLIN) {
 		if (cb->read.thread) {
@@ -285,7 +285,7 @@ int funcname_frrzmq_thread_add_write(struct thread_master *master,
 	else {
 		cb = XCALLOC(MTYPE_ZEROMQ_CB, sizeof(struct frrzmq_cb));
 
-		cb->read.cancelled = 1;
+		cb->read.cancelled = true;
 		*cbp = cb;
 	}
 
@@ -295,7 +295,7 @@ int funcname_frrzmq_thread_add_write(struct thread_master *master,
 	cb->write.cb_msg = msgfunc;
 	cb->write.cb_part = NULL;
 	cb->write.cb_error = errfunc;
-	cb->write.cancelled = 0;
+	cb->write.cancelled = false;
 
 	if (events & ZMQ_POLLOUT) {
 		if (cb->write.thread) {
@@ -316,7 +316,7 @@ void frrzmq_thread_cancel(struct frrzmq_cb **cb, struct cb_core *core)
 {
 	if (!cb || !*cb)
 		return;
-	core->cancelled = 1;
+	core->cancelled = true;
 	if (core->thread) {
 		thread_cancel(core->thread);
 		core->thread = NULL;
diff --git a/lib/libfrr.c b/lib/libfrr.c
index 4fb43edff2..3622890e46 100644
--- a/lib/libfrr.c
+++ b/lib/libfrr.c
@@ -383,7 +383,7 @@ static int frr_opt(int opt)
 		exit(0);
 		break;
 	case 'd':
-		di->daemon_mode = 1;
+		di->daemon_mode = true;
 		break;
 	case 'M':
 		oc = XMALLOC(MTYPE_TMP, sizeof(*oc));
@@ -467,12 +467,12 @@ static int frr_opt(int opt)
 	case 'C':
 		if (di->flags & FRR_NO_CFG_PID_DRY)
 			return 1;
-		di->dryrun = 1;
+		di->dryrun = true;
 		break;
 	case 't':
 		if (di->flags & FRR_NO_CFG_PID_DRY)
 			return 1;
-		di->terminal = 1;
+		di->terminal = true;
 		break;
 	case 'z':
 		di->zpathspace = true;
diff --git a/lib/module.c b/lib/module.c
index 098c550684..14d5cfd44f 100644
--- a/lib/module.c
+++ b/lib/module.c
@@ -58,7 +58,7 @@ static const char *execname = NULL;
 
 void frrmod_init(struct frrmod_runtime *modinfo)
 {
-	modinfo->finished_loading = 1;
+	modinfo->finished_loading = true;
 	*frrmod_last = modinfo;
 	frrmod_last = &modinfo->next;
 
@@ -134,7 +134,7 @@ struct frrmod_runtime *frrmod_load(const char *spec, const char *dir, char *err,
 		goto out_fail;
 	}
 
-	rtinfo->finished_loading = 1;
+	rtinfo->finished_loading = true;
 
 	*frrmod_last = rtinfo;
 	frrmod_last = &rtinfo->next;
diff --git a/lib/northbound.c b/lib/northbound.c
index 206a88d980..cebedcff09 100644
--- a/lib/northbound.c
+++ b/lib/northbound.c
@@ -996,7 +996,7 @@ static int nb_transaction_process(enum nb_event event,
 		 * Only try to release resources that were allocated
 		 * successfully.
 		 */
-		if (event == NB_EV_ABORT && change->prepare_ok == false)
+		if (event == NB_EV_ABORT && !change->prepare_ok)
 			break;
 
 		/* Call the appropriate callback. */
diff --git a/lib/plist.c b/lib/plist.c
index e465963f21..40131aebed 100644
--- a/lib/plist.c
+++ b/lib/plist.c
@@ -2039,7 +2039,7 @@ static void prefix_list_reset_afi(afi_t afi, int orf)
 	assert(master->str.head == NULL);
 	assert(master->str.tail == NULL);
 
-	master->seqnum = 1;
+	master->seqnum = true;
 	master->recent = NULL;
 }
 
diff --git a/lib/routemap.c b/lib/routemap.c
index 64677e8863..f3860924dd 100644
--- a/lib/routemap.c
+++ b/lib/routemap.c
@@ -2447,7 +2447,7 @@ route_map_result_t route_map_apply(struct route_map *map,
 	}
 
 	for (; index; index = index->next) {
-		if (skip_match_clause == false) {
+		if (!skip_match_clause) {
 			/* Apply this index. */
 			match_ret = route_map_apply_match(&index->match_list,
 							  prefix, type, object);
diff --git a/lib/seqlock.c b/lib/seqlock.c
index c05ec19db4..588a1175bc 100644
--- a/lib/seqlock.c
+++ b/lib/seqlock.c
@@ -254,7 +254,7 @@ bool seqlock_check(struct seqlock *sqlo, seqlock_val_t val)
 
 	cur = atomic_load_explicit(&sqlo->pos, memory_order_relaxed);
 	if (!(cur & SEQLOCK_HELD))
-		return 1;
+		return true;
 	cur = SEQLOCK_VAL(cur) - val - 1;
 	assert(cur < 0x40000000 || cur > 0xc0000000);
 	return cur < 0x80000000;
diff --git a/pbrd/pbr_map.c b/pbrd/pbr_map.c
index 37b6be6949..fd77a07fb8 100644
--- a/pbrd/pbr_map.c
+++ b/pbrd/pbr_map.c
@@ -202,7 +202,7 @@ void pbr_map_reason_string(unsigned int reason, char *buf, int size)
 void pbr_map_final_interface_deletion(struct pbr_map *pbrm,
 				      struct pbr_map_interface *pmi)
 {
-	if (pmi->delete == true && !pbr_map_interface_is_installed(pbrm, pmi)) {
+	if (pmi->delete && !pbr_map_interface_is_installed(pbrm, pmi)) {
 		listnode_delete(pbrm->incoming, pmi);
 		pmi->pbrm = NULL;
 
diff --git a/pimd/pim_nht.c b/pimd/pim_nht.c
index 518664f7fb..dd94918b69 100644
--- a/pimd/pim_nht.c
+++ b/pimd/pim_nht.c
@@ -255,7 +255,7 @@ bool pim_nexthop_match(struct pim_instance *pim, struct in_addr addr,
 	int num_ifindex;
 
 	if (addr.s_addr == INADDR_NONE)
-		return 0;
+		return false;
 
 	memset(nexthop_tab, 0,
 	       sizeof(struct pim_zlookup_nexthop) * MULTIPATH_NUM);
@@ -268,7 +268,7 @@ bool pim_nexthop_match(struct pim_instance *pim, struct in_addr addr,
 		zlog_warn(
 			"%s %s: could not find nexthop ifindex for address %s",
 			__FILE__, __PRETTY_FUNCTION__, addr_str);
-		return 0;
+		return false;
 	}
 
 	while (i < num_ifindex) {
@@ -319,12 +319,12 @@ bool pim_nexthop_match(struct pim_instance *pim, struct in_addr addr,
 
 		if (nexthop_tab[i].nexthop_addr.u.prefix4.s_addr
 		    == ip_src.s_addr)
-			return 1;
+			return true;
 
 		i++;
 	}
 
-	return 0;
+	return false;
 }
 
 /* Given a source address and a neighbor address, check if the neighbor is one
@@ -348,7 +348,7 @@ bool pim_nexthop_match_nht_cache(struct pim_instance *pim, struct in_addr addr,
 
 	pnc = pim_nexthop_cache_find(pim, &rpf);
 	if (!pnc || !pnc->nexthop_num)
-		return 0;
+		return false;
 
 	for (nh_node = pnc->nexthop; nh_node; nh_node = nh_node->next) {
 		first_ifindex = nh_node->ifindex;
@@ -398,10 +398,10 @@ bool pim_nexthop_match_nht_cache(struct pim_instance *pim, struct in_addr addr,
 		}
 
 		if (nh_node->gate.ipv4.s_addr == ip_src.s_addr)
-			return 1;
+			return true;
 	}
 
-	return 0;
+	return false;
 }
 
 void pim_rp_nexthop_del(struct rp_info *rp_info)
diff --git a/pimd/pim_upstream.c b/pimd/pim_upstream.c
index 444ab938f2..940b5a33ce 100644
--- a/pimd/pim_upstream.c
+++ b/pimd/pim_upstream.c
@@ -1151,7 +1151,7 @@ static inline bool pim_upstream_is_msdp_peer_sa(struct pim_upstream *up)
  *           AND inherited_olist(S,G) != NULL ) )
  *   }
  */
-int pim_upstream_evaluate_join_desired(struct pim_instance *pim,
+bool pim_upstream_evaluate_join_desired(struct pim_instance *pim,
 				       struct pim_upstream *up)
 {
 	bool empty_imm_oil;
diff --git a/pimd/pim_upstream.h b/pimd/pim_upstream.h
index c717c467dc..4d693b8b64 100644
--- a/pimd/pim_upstream.h
+++ b/pimd/pim_upstream.h
@@ -303,8 +303,8 @@ struct pim_upstream *pim_upstream_del(struct pim_instance *pim,
 				      struct pim_upstream *up,
 				      const char *name);
 
-int pim_upstream_evaluate_join_desired(struct pim_instance *pim,
-				       struct pim_upstream *up);
+bool pim_upstream_evaluate_join_desired(struct pim_instance *pim,
+					struct pim_upstream *up);
 int pim_upstream_evaluate_join_desired_interface(struct pim_upstream *up,
 						 struct pim_ifchannel *ch,
 						 struct pim_ifchannel *starch);
diff --git a/scripts/coccinelle/bool_assignment.cocci b/scripts/coccinelle/bool_assignment.cocci
new file mode 100644
index 0000000000..e6146ea310
--- /dev/null
+++ b/scripts/coccinelle/bool_assignment.cocci
@@ -0,0 +1,13 @@
+@@
+bool b;
+@@
+
+(
+ b =
+- 0
++ false
+|
+ b =
+- 1
++ true
+)
diff --git a/scripts/coccinelle/bool_expression.cocci b/scripts/coccinelle/bool_expression.cocci
new file mode 100644
index 0000000000..c0c329cb59
--- /dev/null
+++ b/scripts/coccinelle/bool_expression.cocci
@@ -0,0 +1,29 @@
+@@
+bool t;
+@@
+
+(
+- t == true
++ t
+|
+- true == t
++ t
+|
+- t != true
++ !t
+|
+- true != t
++ !t
+|
+- t == false
++ !t
+|
+- false == t
++ !t
+|
+- t != false
++ t
+|
+- false != t
++ t
+)
diff --git a/scripts/coccinelle/bool_function.cocci b/scripts/coccinelle/bool_function.cocci
new file mode 100644
index 0000000000..0328ecfbbe
--- /dev/null
+++ b/scripts/coccinelle/bool_function.cocci
@@ -0,0 +1,21 @@
+@@
+identifier fn;
+typedef bool;
+symbol false;
+symbol true;
+@@
+
+bool fn ( ... )
+{
+<...
+return
+(
+- 0
++ false
+|
+- 1
++ true
+)
+  ;
+...>
+}
diff --git a/scripts/coccinelle/bool_function_type.cocci b/scripts/coccinelle/bool_function_type.cocci
new file mode 100644
index 0000000000..71bf4f53b8
--- /dev/null
+++ b/scripts/coccinelle/bool_function_type.cocci
@@ -0,0 +1,19 @@
+@@
+identifier fn;
+typedef bool;
+symbol false;
+symbol true;
+@@
+
+- int
++ bool
+fn (...)
+{
+?...
+return
+(
+  true
+|
+  false
+);
+}
diff --git a/vrrpd/vrrp.c b/vrrpd/vrrp.c
index 03a08dd86b..da6de341e1 100644
--- a/vrrpd/vrrp.c
+++ b/vrrpd/vrrp.c
@@ -953,7 +953,7 @@ static int vrrp_recv_advertisement(struct vrrp_router *r, struct ipaddr *src,
 			thread_add_timer_msec(
 				master, vrrp_master_down_timer_expire, r,
 				r->skew_time * CS2MS, &r->t_master_down_timer);
-		} else if (r->vr->preempt_mode == false
+		} else if (!r->vr->preempt_mode
 			   || pkt->hdr.priority >= r->priority) {
 			if (r->vr->version == 3) {
 				r->master_adver_interval =
@@ -965,7 +965,7 @@ static int vrrp_recv_advertisement(struct vrrp_router *r, struct ipaddr *src,
 					      vrrp_master_down_timer_expire, r,
 					      r->master_down_interval * CS2MS,
 					      &r->t_master_down_timer);
-		} else if (r->vr->preempt_mode == true
+		} else if (r->vr->preempt_mode
 			   && pkt->hdr.priority < r->priority) {
 			/* Discard advertisement */
 			DEBUGD(&vrrp_dbg_proto,
@@ -1834,7 +1834,7 @@ static int vrrp_autoconfig_if_add(struct interface *ifp)
 		created = true;
 	}
 
-	if (!vr || vr->autoconf == false)
+	if (!vr || !vr->autoconf)
 		return 0;
 
 	if (!created) {
@@ -2347,11 +2347,11 @@ static bool vrrp_hash_cmp(const void *arg1, const void *arg2)
 	const struct vrrp_vrouter *vr2 = arg2;
 
 	if (vr1->ifp != vr2->ifp)
-		return 0;
+		return false;
 	if (vr1->vrid != vr2->vrid)
-		return 0;
+		return false;
 
-	return 1;
+	return true;
 }
 
 void vrrp_init(void)
diff --git a/zebra/zebra_mlag.c b/zebra/zebra_mlag.c
index fc7804a409..5b721a8eac 100644
--- a/zebra/zebra_mlag.c
+++ b/zebra/zebra_mlag.c
@@ -605,7 +605,7 @@ int32_t zebra_mlag_test_mlag_internal(const char *none, const char *primary,
 		zsend_capabilities_all_clients();
 		if (zrouter.mlag_info.role != MLAG_ROLE_NONE) {
 			if (zrouter.mlag_info.clients_interested_cnt == 0
-			    && test_mlag_in_progress == false) {
+			    && !test_mlag_in_progress) {
 				if (zrouter.mlag_info.zebra_pth_mlag == NULL)
 					zebra_mlag_spawn_pthread();
 				zrouter.mlag_info.clients_interested_cnt++;
@@ -613,7 +613,7 @@ int32_t zebra_mlag_test_mlag_internal(const char *none, const char *primary,
 				hook_call(zebra_mlag_private_open_channel);
 			}
 		} else {
-			if (test_mlag_in_progress == true) {
+			if (test_mlag_in_progress) {
 				test_mlag_in_progress = false;
 				zrouter.mlag_info.clients_interested_cnt--;
 				hook_call(zebra_mlag_private_close_channel);
@@ -790,7 +790,7 @@ int zebra_mlag_protobuf_encode_client_data(struct stream *s, uint32_t *msg_type)
 					vrf_name_len);
 			}
 		}
-		if (cleanup == false) {
+		if (!cleanup) {
 			Bulk_msg.mroute_add = pay_load;
 			len = zebra_mlag_mroute_add_bulk__pack(&Bulk_msg,
 							       tmp_buf);
@@ -804,7 +804,7 @@ int zebra_mlag_protobuf_encode_client_data(struct stream *s, uint32_t *msg_type)
 			XFREE(MTYPE_MLAG_PBUF, pay_load[i]);
 		}
 		XFREE(MTYPE_MLAG_PBUF, pay_load);
-		if (cleanup == true)
+		if (cleanup)
 			return -1;
 	} break;
 	case MLAG_MROUTE_DEL_BULK: {