diff --git a/include/haproxy/bug.h b/include/haproxy/bug.h
index f19cf8ca7..af086ef8d 100644
--- a/include/haproxy/bug.h
+++ b/include/haproxy/bug.h
@@ -28,6 +28,7 @@
 #ifndef _HAPROXY_BUG_H
 #define _HAPROXY_BUG_H
 
+#include <stddef.h>
 #include <haproxy/atomic.h>
 #include <haproxy/compiler.h>
 
diff --git a/include/haproxy/cbuf-t.h b/include/haproxy/cbuf-t.h
index 27d3bf1a8..fee97c380 100644
--- a/include/haproxy/cbuf-t.h
+++ b/include/haproxy/cbuf-t.h
@@ -27,6 +27,7 @@
 #endif
 #endif
 
+#include <stddef.h>
 #include <haproxy/list-t.h>
 
 extern struct pool_head *pool_head_cbuf;
diff --git a/include/haproxy/defaults.h b/include/haproxy/defaults.h
index 7430c6150..051ca8111 100644
--- a/include/haproxy/defaults.h
+++ b/include/haproxy/defaults.h
@@ -22,6 +22,8 @@
 #ifndef _HAPROXY_DEFAULTS_H
 #define _HAPROXY_DEFAULTS_H
 
+#include <haproxy/compat.h>
+
 /* MAX_THREADS defines the highest limit for the global nbthread value. It
  * defaults to the number of bits in a long integer when threads are enabled
  * but may be lowered to save resources on embedded systems.
diff --git a/include/haproxy/dgram-t.h b/include/haproxy/dgram-t.h
index 4e4c2afef..5ed24ef50 100644
--- a/include/haproxy/dgram-t.h
+++ b/include/haproxy/dgram-t.h
@@ -22,6 +22,8 @@
 #ifndef _HAPROXY_HAPROXY_DGRAM_T_H
 #define _HAPROXY_HAPROXY_DGRAM_T_H
 
+#include <haproxy/api-t.h>
+#include <haproxy/thread-t.h>
 #include <arpa/inet.h>
 
 /*
diff --git a/include/haproxy/dynbuf-t.h b/include/haproxy/dynbuf-t.h
index b5545ab26..078ea41e7 100644
--- a/include/haproxy/dynbuf-t.h
+++ b/include/haproxy/dynbuf-t.h
@@ -22,6 +22,7 @@
 #ifndef _HAPROXY_DYNBUF_T_H
 #define _HAPROXY_DYNBUF_T_H
 
+#include <haproxy/list-t.h>
 
 /* an element of the <buffer_wq> list. It represents an object that need to
  * acquire a buffer to continue its process. */
diff --git a/include/haproxy/filters-t.h b/include/haproxy/filters-t.h
index c86ef6f3d..2acacd076 100644
--- a/include/haproxy/filters-t.h
+++ b/include/haproxy/filters-t.h
@@ -22,6 +22,7 @@
 #define _HAPROXY_FILTERS_T_H
 
 #include <haproxy/api-t.h>
+#include <haproxy/buf-t.h>
 
 /* Flags set on a filter config */
 #define FLT_CFG_FL_HTX    0x00000001  /* The filter can filter HTX streams */
diff --git a/include/haproxy/http_client.h b/include/haproxy/http_client.h
index 241ca24ce..93f3fc1af 100644
--- a/include/haproxy/http_client.h
+++ b/include/haproxy/http_client.h
@@ -1,6 +1,7 @@
 #ifndef _HAPROXY_HTTPCLIENT_H
 #define _HAPROXY_HTTPCLIENT_H
 
+#include <haproxy/buf.h>
 #include <haproxy/http_client-t.h>
 
 void httpclient_destroy(struct httpclient *hc);
diff --git a/include/haproxy/jwt-t.h b/include/haproxy/jwt-t.h
index e94607eea..d4f9e69dc 100644
--- a/include/haproxy/jwt-t.h
+++ b/include/haproxy/jwt-t.h
@@ -22,6 +22,7 @@
 #ifndef _HAPROXY_JWT_T_H
 #define _HAPROXY_JWT_T_H
 
+#include <import/ebmbtree.h>
 #include <haproxy/openssl-compat.h>
 
 #ifdef USE_OPENSSL
diff --git a/include/haproxy/mqtt-t.h b/include/haproxy/mqtt-t.h
index 51f55ea51..3af2d1158 100644
--- a/include/haproxy/mqtt-t.h
+++ b/include/haproxy/mqtt-t.h
@@ -22,6 +22,7 @@
 #ifndef _HAPROXY_MQTT_T_H
 #define _HAPROXY_MQTT_T_H
 
+#include <inttypes.h>
 #include <import/ist.h>
 
 /* MQTT protocol version
diff --git a/include/haproxy/proto_quic.h b/include/haproxy/proto_quic.h
index a0e2b9816..b420f3545 100644
--- a/include/haproxy/proto_quic.h
+++ b/include/haproxy/proto_quic.h
@@ -21,6 +21,10 @@
 #ifndef _HAPROXY_PROTO_QUIC_H
 #define _HAPROXY_PROTO_QUIC_H
 
+#include <import/ebtree.h>
+#include <haproxy/api-t.h>
+#include <haproxy/thread-t.h>
+
 extern struct protocol proto_quic4;
 extern struct protocol proto_quic6;
 
diff --git a/include/haproxy/proto_sockpair.h b/include/haproxy/proto_sockpair.h
index bb0256e8d..e8cb2ac0f 100644
--- a/include/haproxy/proto_sockpair.h
+++ b/include/haproxy/proto_sockpair.h
@@ -21,6 +21,8 @@
 #ifndef _HAPROXY_PROTO_SOCKPAIR_H
 #define _HAPROXY_PROTO_SOCKPAIR_H
 
+#include <haproxy/receiver-t.h>
+
 extern struct proto_fam proto_fam_sockpair;
 extern struct protocol proto_sockpair;
 
diff --git a/include/haproxy/proto_udp.h b/include/haproxy/proto_udp.h
index 1c4da77c9..6475bf9e9 100644
--- a/include/haproxy/proto_udp.h
+++ b/include/haproxy/proto_udp.h
@@ -24,6 +24,8 @@
 #ifndef _PROTO_PROTO_UDP_H
 #define _PROTO_PROTO_UDP_H
 
+#include <haproxy/receiver-t.h>
+
 extern struct protocol proto_udp4;
 extern struct protocol proto_udp6;
 
diff --git a/include/haproxy/qpack-dec.h b/include/haproxy/qpack-dec.h
index 993f4509e..8ea768968 100644
--- a/include/haproxy/qpack-dec.h
+++ b/include/haproxy/qpack-dec.h
@@ -21,6 +21,8 @@
 #ifndef _HAPROXY_QPACK_DEC_H
 #define _HAPROXY_QPACK_DEC_H
 
+#include <inttypes.h>
+
 struct buffer;
 struct http_hdr;
 
diff --git a/include/haproxy/qpack-tbl-t.h b/include/haproxy/qpack-tbl-t.h
index c27c6233f..7b3e2f9c2 100644
--- a/include/haproxy/qpack-tbl-t.h
+++ b/include/haproxy/qpack-tbl-t.h
@@ -26,6 +26,8 @@
 #ifndef _HAPROXY_QPACK_TBL_T_H
 #define _HAPROXY_QPACK_TBL_T_H
 
+#include <inttypes.h>
+
 /*
  * Gcc before 3.0 needs [0] to declare a variable-size array
  */
diff --git a/include/haproxy/queue-t.h b/include/haproxy/queue-t.h
index 8f6a1ec8d..7d9c31cf8 100644
--- a/include/haproxy/queue-t.h
+++ b/include/haproxy/queue-t.h
@@ -24,6 +24,7 @@
 
 #include <import/ebtree-t.h>
 #include <haproxy/api-t.h>
+#include <haproxy/thread-t.h>
 
 struct proxy;
 struct server;
diff --git a/include/haproxy/quic_ack-t.h b/include/haproxy/quic_ack-t.h
index 95b77f1c9..64182e6db 100644
--- a/include/haproxy/quic_ack-t.h
+++ b/include/haproxy/quic_ack-t.h
@@ -13,6 +13,10 @@
 #ifndef _HAPROXY_QUIC_ACK_T_H
 #define _HAPROXY_QUIC_ACK_T_H
 
+#include <inttypes.h>
+#include <stddef.h>
+#include <import/eb64tree.h>
+
 /* The maximum number of ack ranges to be built in ACK frames */
 #define QUIC_MAX_ACK_RANGES   32
 
diff --git a/include/haproxy/quic_ack.h b/include/haproxy/quic_ack.h
index 540e2c08c..baa27ac05 100644
--- a/include/haproxy/quic_ack.h
+++ b/include/haproxy/quic_ack.h
@@ -13,6 +13,12 @@
 #ifndef _HAPROXY_QUIC_ACK_H
 #define _HAPROXY_QUIC_ACK_H
 
+#include <inttypes.h>
+
+struct quic_conn;
+struct quic_arng;
+struct quic_arngs;
+
 void quic_free_arngs(struct quic_conn *qc, struct quic_arngs *arngs);
 int quic_update_ack_ranges_list(struct quic_conn *qc,
                                 struct quic_arngs *arngs,
diff --git a/include/haproxy/quic_rx-t.h b/include/haproxy/quic_rx-t.h
index 9ef8e7a2f..6b5a0c4c9 100644
--- a/include/haproxy/quic_rx-t.h
+++ b/include/haproxy/quic_rx-t.h
@@ -5,6 +5,13 @@ extern struct pool_head *pool_head_quic_conn_rxbuf;
 extern struct pool_head *pool_head_quic_dgram;
 extern struct pool_head *pool_head_quic_rx_packet;
 
+#include <import/eb64tree.h>
+#include <haproxy/api-t.h>
+#include <haproxy/quic_cid-t.h>
+#include <inttypes.h>
+#include <sys/socket.h>
+
+struct quic_version;
 /* Maximum number of ack-eliciting received packets since the last
  * ACK frame was sent
  */
diff --git a/include/haproxy/quic_tls-t.h b/include/haproxy/quic_tls-t.h
index ae65149b5..95f77dfc6 100644
--- a/include/haproxy/quic_tls-t.h
+++ b/include/haproxy/quic_tls-t.h
@@ -21,6 +21,7 @@
 
 #include <import/ebtree.h>
 
+#include <haproxy/buf-t.h>
 #include <haproxy/ncbuf-t.h>
 #include <haproxy/quic_ack-t.h>
 #include <haproxy/openssl-compat.h>
diff --git a/include/haproxy/quic_tx-t.h b/include/haproxy/quic_tx-t.h
index 4653f04d0..697920485 100644
--- a/include/haproxy/quic_tx-t.h
+++ b/include/haproxy/quic_tx-t.h
@@ -5,6 +5,9 @@
 #define QUIC_DGRAM_HEADLEN  (sizeof(uint16_t) + sizeof(void *))
 #define QUIC_MAX_CC_BUFSIZE (2 * (QUIC_MIN_CC_PKTSIZE + QUIC_DGRAM_HEADLEN))
 
+#include <import/eb64tree.h>
+#include <haproxy/list-t.h>
+
 extern struct pool_head *pool_head_quic_tx_packet;
 extern struct pool_head *pool_head_quic_cc_buf;
 
diff --git a/include/haproxy/ssl_gencert.h b/include/haproxy/ssl_gencert.h
index 4f9510e01..9065934bf 100644
--- a/include/haproxy/ssl_gencert.h
+++ b/include/haproxy/ssl_gencert.h
@@ -21,6 +21,9 @@
 #define _HAPROXY_SSL_GENCERT_H
 #ifdef USE_OPENSSL
 
+#include <haproxy/listener-t.h>
+#include <haproxy/ssl_sock-t.h>
+
 int ssl_sock_generate_certificate(const char *servername, struct bind_conf *bind_conf, SSL *ssl);
 int ssl_sock_generate_certificate_from_conn(struct bind_conf *bind_conf, SSL *ssl);
 SSL_CTX *ssl_sock_assign_generated_cert(unsigned int key, struct bind_conf *bind_conf, SSL *ssl);
diff --git a/include/haproxy/stick_table.h b/include/haproxy/stick_table.h
index 1c1ed61ce..26b612192 100644
--- a/include/haproxy/stick_table.h
+++ b/include/haproxy/stick_table.h
@@ -29,6 +29,7 @@
 #include <haproxy/freq_ctr.h>
 #include <haproxy/sample-t.h>
 #include <haproxy/stick_table-t.h>
+#include <haproxy/thread.h>
 #include <haproxy/ticks.h>
 
 extern struct stktable *stktables_list;
diff --git a/include/haproxy/tools-t.h b/include/haproxy/tools-t.h
index 32d8193fe..38762ac2b 100644
--- a/include/haproxy/tools-t.h
+++ b/include/haproxy/tools-t.h
@@ -22,6 +22,8 @@
 #ifndef _HAPROXY_TOOLS_T_H
 #define _HAPROXY_TOOLS_T_H
 
+#include <netinet/in.h>
+
 /* size used for max length of decimal representation of long long int. */
 #define NB_LLMAX_STR (sizeof("-9223372036854775807")-1)
 
diff --git a/include/haproxy/vars.h b/include/haproxy/vars.h
index ebd1f1579..33ee94665 100644
--- a/include/haproxy/vars.h
+++ b/include/haproxy/vars.h
@@ -25,9 +25,12 @@
 #include <haproxy/api-t.h>
 #include <haproxy/session-t.h>
 #include <haproxy/stream-t.h>
+#include <haproxy/thread.h>
 #include <haproxy/vars-t.h>
 
 extern struct vars proc_vars;
+struct sample;
+struct arg;
 
 void vars_init_head(struct vars *vars, enum vars_scope scope);
 void var_accounting_diff(struct vars *vars, struct session *sess, struct stream *strm, int size);
diff --git a/include/haproxy/xref.h b/include/haproxy/xref.h
index 42eed5808..25f9d3ca0 100644
--- a/include/haproxy/xref.h
+++ b/include/haproxy/xref.h
@@ -28,6 +28,7 @@
 #ifndef __HAPROXY_XREF_H__
 #define __HAPROXY_XREF_H__
 
+#include <haproxy/api.h>
 #include <haproxy/xref-t.h>
 
 /* xref is used to create relation between two elements.
diff --git a/include/import/slz-tables.h b/include/import/slz-tables.h
index 0b3a5b963..6e6d658a2 100644
--- a/include/import/slz-tables.h
+++ b/include/import/slz-tables.h
@@ -1,3 +1,5 @@
+#include <inttypes.h>
+
 /* Fixed Huffman table as per RFC1951.
  *
  *       Lit Value    Bits        Codes