diff --git a/include/stellar/layer.h b/include/stellar/layer.h
index 7687102..0ec9699 100644
--- a/include/stellar/layer.h
+++ b/include/stellar/layer.h
@@ -1,5 +1,4 @@
-#ifndef _LAYER_H
-#define _LAYER_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -90,5 +89,3 @@ int packet_get_layer_by_idx(const struct packet *pkt, int idx, struct layer *out
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/include/stellar/packet.h b/include/stellar/packet.h
index 62b03e7..16efe2a 100644
--- a/include/stellar/packet.h
+++ b/include/stellar/packet.h
@@ -1,5 +1,4 @@
-#ifndef _PACKET_H
-#define _PACKET_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -43,5 +42,3 @@ uint16_t packet_get_payload_len(const struct packet *pkt);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/include/stellar/session.h b/include/stellar/session.h
index 5fb58fa..d62086d 100644
--- a/include/stellar/session.h
+++ b/include/stellar/session.h
@@ -1,5 +1,4 @@
-#ifndef _SESSION_PUB_H
-#define _SESSION_PUB_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -150,5 +149,3 @@ void session_set_discard(struct session *sess);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/include/stellar/stellar.h b/include/stellar/stellar.h
index 598b279..0f02132 100644
--- a/include/stellar/stellar.h
+++ b/include/stellar/stellar.h
@@ -1,5 +1,4 @@
-#ifndef _STELLAR_PUB_H
-#define _STELLAR_PUB_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -63,5 +62,3 @@ int stellar_main(int argc, char **argv);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/include/stellar/tunnel.h b/include/stellar/tunnel.h
index e51cc99..81d0526 100644
--- a/include/stellar/tunnel.h
+++ b/include/stellar/tunnel.h
@@ -1,5 +1,4 @@
-#ifndef _TUNNEL_H
-#define _TUNNEL_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -59,5 +58,3 @@ int packet_get_tunnel_by_idx(const struct packet *pkt, int idx, struct tunnel *o
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/crc32/crc32_hash.h b/src/crc32/crc32_hash.h
index 180912f..f49cfe8 100644
--- a/src/crc32/crc32_hash.h
+++ b/src/crc32/crc32_hash.h
@@ -1,5 +1,4 @@
-#ifndef _CRC32_HASH_H_
-#define _CRC32_HASH_H_
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -354,5 +353,3 @@ static inline uint32_t crc32_hash(const void *data, uint32_t data_len, uint32_t
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/duplicated_packet_filter/duplicated_packet_filter.h b/src/duplicated_packet_filter/duplicated_packet_filter.h
index a1cd794..14b88d5 100644
--- a/src/duplicated_packet_filter/duplicated_packet_filter.h
+++ b/src/duplicated_packet_filter/duplicated_packet_filter.h
@@ -1,5 +1,4 @@
-#ifndef _DUPLICATED_PACKET_H_
-#define _DUPLICATED_PACKET_H_
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -25,5 +24,3 @@ void duplicated_packet_filter_add(struct duplicated_packet_filter *filter, const
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/evicted_session_filter/evicted_session_filter.h b/src/evicted_session_filter/evicted_session_filter.h
index 262b77d..480e3c2 100644
--- a/src/evicted_session_filter/evicted_session_filter.h
+++ b/src/evicted_session_filter/evicted_session_filter.h
@@ -1,5 +1,4 @@
-#ifndef _EVICTED_SESSION_FILTER_H_
-#define _EVICTED_SESSION_FILTER_H_
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -22,5 +21,3 @@ void evicted_session_filter_add(struct evicted_session_filter *filter, const str
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/id_generator/id_generator.h b/src/id_generator/id_generator.h
index 2b291af..c100264 100644
--- a/src/id_generator/id_generator.h
+++ b/src/id_generator/id_generator.h
@@ -1,5 +1,4 @@
-#ifndef _ID_GENERATOR_H
-#define _ID_GENERATOR_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -27,5 +26,3 @@ uint64_t id_generator_alloc();
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/ip_reassembly/ip_reassembly.h b/src/ip_reassembly/ip_reassembly.h
index f9a7059..6162396 100644
--- a/src/ip_reassembly/ip_reassembly.h
+++ b/src/ip_reassembly/ip_reassembly.h
@@ -1,5 +1,4 @@
-#ifndef _IP_REASSEMBLE_H
-#define _IP_REASSEMBLE_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -65,5 +64,3 @@ struct packet *ipv6_reassembly_packet(struct ip_reassembly *assy, const struct p
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/ip_reassembly/test/gtest_utils.h b/src/ip_reassembly/test/gtest_utils.h
index 1ef4772..5ff9b8d 100644
--- a/src/ip_reassembly/test/gtest_utils.h
+++ b/src/ip_reassembly/test/gtest_utils.h
@@ -1,5 +1,4 @@
-#ifndef _GTEST_UTILS_H
-#define _GTEST_UTILS_H
+#pragma once
 
 #include <gtest/gtest.h>
 
@@ -82,5 +81,3 @@ static inline void check_stat(struct ip_reassembly_stat *stat,
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/log/log.h b/src/log/log.h
index d5cdb6b..1f9864f 100644
--- a/src/log/log.h
+++ b/src/log/log.h
@@ -1,5 +1,4 @@
-#ifndef _LOG_H
-#define _LOG_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -72,5 +71,3 @@ void log_print(enum log_level level, const char *module, const char *fmt, ...);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet/checksum.h b/src/packet/checksum.h
index afc5191..cb4fe7d 100644
--- a/src/packet/checksum.h
+++ b/src/packet/checksum.h
@@ -1,5 +1,4 @@
-#ifndef _CHECKSUM_H
-#define _CHECKSUM_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -37,5 +36,3 @@ static inline uint16_t checksum(char *data, int len)
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet/eth_utils.h b/src/packet/eth_utils.h
index 30d65fa..d545c25 100644
--- a/src/packet/eth_utils.h
+++ b/src/packet/eth_utils.h
@@ -1,5 +1,4 @@
-#ifndef _ETH_UTILS_H
-#define _ETH_UTILS_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -292,5 +291,3 @@ static inline int eth_hdr_to_str(const struct ethhdr *hdr, char *buf, size_t siz
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet/gre_utils.h b/src/packet/gre_utils.h
index a330a05..b71b103 100644
--- a/src/packet/gre_utils.h
+++ b/src/packet/gre_utils.h
@@ -1,5 +1,4 @@
-#ifndef _GRE_UTILS_H
-#define _GRE_UTILS_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -179,5 +178,3 @@ static inline int gre_hdr_to_str(const struct gre_hdr *hdr, char *buf, size_t si
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet/ipv4_utils.h b/src/packet/ipv4_utils.h
index f2dc3a0..a24a9ab 100644
--- a/src/packet/ipv4_utils.h
+++ b/src/packet/ipv4_utils.h
@@ -1,5 +1,4 @@
-#ifndef _IPV4_UTILS_H
-#define _IPV4_UTILS_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -389,5 +388,3 @@ static inline int ipv4_hdr_to_str(const struct ip *hdr, char *buf, size_t size)
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet/ipv6_utils.h b/src/packet/ipv6_utils.h
index b7e9cc2..6ac3f13 100644
--- a/src/packet/ipv6_utils.h
+++ b/src/packet/ipv6_utils.h
@@ -1,5 +1,4 @@
-#ifndef _IPV6_UTILS_H
-#define _IPV6_UTILS_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -220,5 +219,3 @@ static inline int ipv6_hdr_to_str(const struct ip6_hdr *hdr, char *buf, size_t s
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet/l2tp_utils.h b/src/packet/l2tp_utils.h
index 35949d4..9d4ff97 100644
--- a/src/packet/l2tp_utils.h
+++ b/src/packet/l2tp_utils.h
@@ -1,5 +1,4 @@
-#ifndef _L2TP_UTILS_H
-#define _L2TP_UTILS_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -260,5 +259,3 @@ static inline int l2tp_hdr_to_str(const struct l2tp_hdr *hdr, char *buf, size_t
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet/mpls_utils.h b/src/packet/mpls_utils.h
index c6571d8..e0b91e9 100644
--- a/src/packet/mpls_utils.h
+++ b/src/packet/mpls_utils.h
@@ -1,5 +1,4 @@
-#ifndef _MPLS_UTILS_H
-#define _MPLS_UTILS_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -83,5 +82,3 @@ static inline int mpls_label_to_str(const struct mpls_label *hdr, char *buf, siz
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet/packet_priv.h b/src/packet/packet_priv.h
index e5acc2f..418799c 100644
--- a/src/packet/packet_priv.h
+++ b/src/packet/packet_priv.h
@@ -1,5 +1,4 @@
-#ifndef _PACKET_PRIV_H
-#define _PACKET_PRIV_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -103,5 +102,3 @@ uint64_t packet_get_hash(const struct packet *pkt, enum ldbc_method method, int
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet/packet_utils.h b/src/packet/packet_utils.h
index f609556..d71daef 100644
--- a/src/packet/packet_utils.h
+++ b/src/packet/packet_utils.h
@@ -1,5 +1,4 @@
-#ifndef _PACKET_UTILS_H
-#define _PACKET_UTILS_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -55,5 +54,3 @@ void layer_convert(const struct raw_layer *in, struct layer *out);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet/tcp_utils.h b/src/packet/tcp_utils.h
index e96968f..f01fe62 100644
--- a/src/packet/tcp_utils.h
+++ b/src/packet/tcp_utils.h
@@ -1,5 +1,4 @@
-#ifndef _TCP_UTILS_H
-#define _TCP_UTILS_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -286,5 +285,3 @@ static inline int tcp_hdr_to_str(const struct tcphdr *hdr, char *buf, size_t siz
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet/udp_utils.h b/src/packet/udp_utils.h
index 6b2ec01..0c2a767 100644
--- a/src/packet/udp_utils.h
+++ b/src/packet/udp_utils.h
@@ -1,5 +1,4 @@
-#ifndef _UDP_UTILS_H
-#define _UDP_UTILS_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -89,5 +88,3 @@ static inline int udp_hdr_to_str(const struct udphdr *hdr, char *buf, size_t siz
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet/vlan_utils.h b/src/packet/vlan_utils.h
index 5cc52bb..69793a2 100644
--- a/src/packet/vlan_utils.h
+++ b/src/packet/vlan_utils.h
@@ -1,5 +1,4 @@
-#ifndef _VLAN_UTILS_H
-#define _VLAN_UTILS_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -91,5 +90,3 @@ static inline int vlan_hdr_to_str(const struct vlan_hdr *hdr, char *buf, size_t
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet/vxlan_utils.h b/src/packet/vxlan_utils.h
index 57a9c9e..125edd8 100644
--- a/src/packet/vxlan_utils.h
+++ b/src/packet/vxlan_utils.h
@@ -1,5 +1,4 @@
-#ifndef _VXLAN_UTILS_H
-#define _VXLAN_UTILS_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -70,5 +69,3 @@ static inline int vxlan_hdr_to_str(const struct vxlan_hdr *hdr, char *buf, size_
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet_io/dumpfile_io.h b/src/packet_io/dumpfile_io.h
index fb9c7a8..0e9d8f5 100644
--- a/src/packet_io/dumpfile_io.h
+++ b/src/packet_io/dumpfile_io.h
@@ -1,5 +1,4 @@
-#ifndef _DUMPFILE_IO_H
-#define _DUMPFILE_IO_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -24,5 +23,3 @@ struct io_stat *dumpfile_io_stat(struct dumpfile_io *handle, uint16_t thr_idx);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet_io/lock_free_queue.h b/src/packet_io/lock_free_queue.h
index e6e0978..584f561 100644
--- a/src/packet_io/lock_free_queue.h
+++ b/src/packet_io/lock_free_queue.h
@@ -1,5 +1,4 @@
-#ifndef _LOCK_FREE_QUEUE_H
-#define _LOCK_FREE_QUEUE_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -23,5 +22,3 @@ void lock_free_queue_pop(struct lock_free_queue *queue, void **data);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet_io/marsio_io.h b/src/packet_io/marsio_io.h
index 658b1fd..0db5fe2 100644
--- a/src/packet_io/marsio_io.h
+++ b/src/packet_io/marsio_io.h
@@ -1,5 +1,4 @@
-#ifndef _MARSIO_IO_H
-#define _MARSIO_IO_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -23,5 +22,3 @@ struct io_stat *marsio_io_stat(struct marsio_io *handle, uint16_t thr_idx);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/packet_io/packet_io.h b/src/packet_io/packet_io.h
index f45ef06..26e695e 100644
--- a/src/packet_io/packet_io.h
+++ b/src/packet_io/packet_io.h
@@ -1,5 +1,4 @@
-#ifndef _PACKET_IO_H
-#define _PACKET_IO_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -87,5 +86,3 @@ struct io_stat *packet_io_stat(struct packet_io *packet_io, uint16_t thr_idx);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/plugin/plugin_manager.h b/src/plugin/plugin_manager.h
index ae7577d..b6dd98f 100644
--- a/src/plugin/plugin_manager.h
+++ b/src/plugin/plugin_manager.h
@@ -1,5 +1,4 @@
-#ifndef _PLUGIN_MANAGER_H
-#define _PLUGIN_MANAGER_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -32,5 +31,3 @@ void plugin_manager_session_runtime_free(struct plugin_manager_runtime *plug_mgr
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/session/session_manager.h b/src/session/session_manager.h
index 888c1ae..48cf685 100644
--- a/src/session/session_manager.h
+++ b/src/session/session_manager.h
@@ -1,5 +1,4 @@
-#ifndef _SESSION_MANAGER_H
-#define _SESSION_MANAGER_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -120,5 +119,3 @@ struct session_manager_stat *session_manager_stat(struct session_manager *mgr);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/session/session_pool.h b/src/session/session_pool.h
index 3344dad..76433a5 100644
--- a/src/session/session_pool.h
+++ b/src/session/session_pool.h
@@ -1,5 +1,4 @@
-#ifndef _SESSION_POOL_H
-#define _SESSION_POOL_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -19,5 +18,3 @@ uint64_t session_pool_get_count(struct session_pool *pool);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/session/session_priv.h b/src/session/session_priv.h
index cead0f0..c596b98 100644
--- a/src/session/session_priv.h
+++ b/src/session/session_priv.h
@@ -1,5 +1,4 @@
-#ifndef _SESSION_PRIV_H
-#define _SESSION_PRIV_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -161,5 +160,3 @@ int session_to_json(struct session *sess, char *buff, int size);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/session/session_table.h b/src/session/session_table.h
index a4751ff..d543543 100644
--- a/src/session/session_table.h
+++ b/src/session/session_table.h
@@ -1,5 +1,4 @@
-#ifndef _SESSION_TABLE_H
-#define _SESSION_TABLE_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -25,5 +24,3 @@ struct session *session_table_find_lru(struct session_table *table);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/session/session_timer.h b/src/session/session_timer.h
index 87368e2..074522a 100644
--- a/src/session/session_timer.h
+++ b/src/session/session_timer.h
@@ -1,5 +1,4 @@
-#ifndef _SESSION_TIMER_H
-#define _SESSION_TIMER_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -26,5 +25,3 @@ uint64_t session_timer_next_expire_interval(struct session_timer *timer);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/session/session_transition.h b/src/session/session_transition.h
index e52de08..a23031d 100644
--- a/src/session/session_transition.h
+++ b/src/session/session_transition.h
@@ -1,5 +1,4 @@
-#ifndef _SESSION_TRANSITION_H
-#define _SESSION_TRANSITION_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -43,5 +42,3 @@ void session_transition_log(struct session *sess, enum session_state curr_state,
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/session/test/test_packets.h b/src/session/test/test_packets.h
index 2f05b4b..e2f0225 100644
--- a/src/session/test/test_packets.h
+++ b/src/session/test/test_packets.h
@@ -1,5 +1,4 @@
-#ifndef _TEST_PACKETS_H
-#define _TEST_PACKETS_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -2701,5 +2700,3 @@ unsigned char tcp_out_of_order_pkt7[] = {
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/stellar/config.h b/src/stellar/config.h
index c5e49ad..dc7c822 100644
--- a/src/stellar/config.h
+++ b/src/stellar/config.h
@@ -1,5 +1,4 @@
-#ifndef _CONFIG_H
-#define _CONFIG_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -33,5 +32,3 @@ void stellar_print_config(struct stellar_config *config);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/stellar/logo.h b/src/stellar/logo.h
index 9dc6cb6..2bd85b9 100644
--- a/src/stellar/logo.h
+++ b/src/stellar/logo.h
@@ -1,5 +1,4 @@
-#ifndef _LOGO_H
-#define _LOGO_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -23,5 +22,3 @@ static const char logo_str[] =
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/stellar/macro.h b/src/stellar/macro.h
index 8b545b4..705dd58 100644
--- a/src/stellar/macro.h
+++ b/src/stellar/macro.h
@@ -1,5 +1,4 @@
-#ifndef _MACRO_H
-#define _MACRO_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -29,5 +28,3 @@ extern "C"
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/stellar/stat.h b/src/stellar/stat.h
index 4f41a59..c8983c8 100644
--- a/src/stellar/stat.h
+++ b/src/stellar/stat.h
@@ -1,5 +1,4 @@
-#ifndef _STAT_H
-#define _STAT_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -28,5 +27,3 @@ void stellar_stat_merge(struct stellar_stat *stat, const struct thread_stat *thr
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/stellar/stellar_priv.h b/src/stellar/stellar_priv.h
index 17befbc..67ff904 100644
--- a/src/stellar/stellar_priv.h
+++ b/src/stellar/stellar_priv.h
@@ -1,5 +1,4 @@
-#ifndef _STELLAR_PRIV_H
-#define _STELLAR_PRIV_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -20,5 +19,3 @@ void stellar_set_plugin_manger(struct stellar *st, struct plugin_manager_schema
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/tcp_reassembly/tcp_reassembly.h b/src/tcp_reassembly/tcp_reassembly.h
index e035ad0..f135274 100644
--- a/src/tcp_reassembly/tcp_reassembly.h
+++ b/src/tcp_reassembly/tcp_reassembly.h
@@ -1,5 +1,4 @@
-#ifndef _TCP_REASSEMBLY_H
-#define _TCP_REASSEMBLY_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -66,5 +65,3 @@ static inline uint32_t uint32_add(uint32_t seq, uint32_t inc)
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/times/times.h b/src/times/times.h
index 73549fe..c426a17 100644
--- a/src/times/times.h
+++ b/src/times/times.h
@@ -1,5 +1,4 @@
-#ifndef _TIMES_H
-#define _TIMES_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -19,5 +18,3 @@ uint64_t stellar_get_real_time_msec();
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/src/tuple/tuple.h b/src/tuple/tuple.h
index 15bae48..a32041f 100644
--- a/src/tuple/tuple.h
+++ b/src/tuple/tuple.h
@@ -1,5 +1,4 @@
-#ifndef _TUPLE_H
-#define _TUPLE_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -85,5 +84,3 @@ void tuple6_to_str(const struct tuple6 *tuple, char *buf, uint32_t size);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/test/packet_inject/packet_inject_main.h b/test/packet_inject/packet_inject_main.h
index eaa688b..7953ae9 100644
--- a/test/packet_inject/packet_inject_main.h
+++ b/test/packet_inject/packet_inject_main.h
@@ -1,5 +1,4 @@
-#ifndef _PACKET_INJECT_MAIN_H
-#define _PACKET_INJECT_MAIN_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -43,5 +42,3 @@ int packet_inject_main(int argc, char **argv);
 #ifdef __cplusplus
 }
 #endif
-
-#endif
diff --git a/test/packet_inject/packet_inject_test.h b/test/packet_inject/packet_inject_test.h
index 6722f89..0c5511b 100644
--- a/test/packet_inject/packet_inject_test.h
+++ b/test/packet_inject/packet_inject_test.h
@@ -1,5 +1,4 @@
-#ifndef _PACKET_INJECT_TEST_H
-#define _PACKET_INJECT_TEST_H
+#pragma once
 
 #ifdef __cplusplus
 extern "C"
@@ -32,5 +31,3 @@ void packet_inject_test(struct packet_inject_case *test);
 #ifdef __cplusplus
 }
 #endif
-
-#endif