diff --git a/src/Makefile.am b/src/Makefile.am
index b9ce208d..e2233d72 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -5,6 +5,7 @@ SUBDIRS = common/avl common/net common/thread common/httpp common/log common/tim
 bin_PROGRAMS = icecast
 
 noinst_HEADERS = \
+    icecasttypes.h \
     admin.h \
     main.h \
     cfgfile.h \
diff --git a/src/acl.c b/src/acl.c
index b8fa0393..80494572 100644
--- a/src/acl.c
+++ b/src/acl.c
@@ -16,6 +16,7 @@
 
 #include "acl.h"
 #include "admin.h"
+#include "util.h"
 
 #include <stdio.h>
 
diff --git a/src/acl.h b/src/acl.h
index 03101a68..aec52c82 100644
--- a/src/acl.h
+++ b/src/acl.h
@@ -18,10 +18,7 @@
 #include <libxml/tree.h>
 #include "common/httpp/httpp.h"
 
-struct acl_tag;
-typedef struct acl_tag acl_t;
-
-#include "admin.h"
+#include "icecasttypes.h"
 
 typedef enum acl_policy_tag {
  /* Error on function call */
diff --git a/src/admin.c b/src/admin.c
index b4edcf12..667ae59f 100644
--- a/src/admin.c
+++ b/src/admin.c
@@ -23,6 +23,8 @@
 #include <libxml/parser.h>
 #include <libxml/tree.h>
 
+#include "admin.h"
+#include "compat.h"
 #include "cfgfile.h"
 #include "connection.h"
 #include "refbuf.h"
@@ -30,16 +32,15 @@
 #include "source.h"
 #include "global.h"
 #include "stats.h"
-#include "compat.h"
 #include "xslt.h"
 #include "fserve.h"
-#include "admin.h"
 #include "errors.h"
 
 #include "format.h"
 
 #include "logging.h"
 #include "auth.h"
+#include "acl.h"
 #ifdef _WIN32
 #define snprintf _snprintf
 #endif
diff --git a/src/admin.h b/src/admin.h
index d0770414..06945d2d 100644
--- a/src/admin.h
+++ b/src/admin.h
@@ -16,24 +16,9 @@
 
 #include <libxml/parser.h>
 #include <libxml/tree.h>
-#include <stdint.h>
-
-/* Command IDs */
-typedef int32_t admin_command_id_t;
-
-/* formats */
-typedef enum {
-    ADMIN_FORMAT_AUTO,
-    ADMIN_FORMAT_RAW,
-    ADMIN_FORMAT_TRANSFORMED,
-    ADMIN_FORMAT_PLAINTEXT
-} admin_format_t;
 
+#include "icecasttypes.h"
 #include "compat.h"
-#include "refbuf.h"
-#include "client.h"
-#include "source.h"
-#include "auth.h"
 
 /* types */
 #define ADMINTYPE_ERROR   (-1)
diff --git a/src/auth.h b/src/auth.h
index f0795ebb..12a0b17c 100644
--- a/src/auth.h
+++ b/src/auth.h
@@ -18,15 +18,14 @@
 #include <config.h>
 #endif
 
-struct source_tag;
-typedef struct auth_tag auth_t;
-
 #include <libxml/xmlmemory.h>
 #include <libxml/parser.h>
 #include <libxml/tree.h>
-#include "cfgfile.h"
-#include "client.h"
+
 #include "common/thread/thread.h"
+#include "common/httpp/httpp.h"
+
+#include "icecasttypes.h"
 
 /* implemented */
 #define AUTH_TYPE_ANONYMOUS       "anonymous"
@@ -58,7 +57,7 @@ typedef enum
 typedef struct auth_client_tag
 {
     client_t     *client;
-    auth_result (*process)(struct auth_tag *auth, struct auth_client_tag *auth_user);
+    auth_result (*process)(auth_t *auth, struct auth_client_tag *auth_user);
     void        (*on_no_match)(client_t *client, void (*on_result)(client_t *client, void *userdata, auth_result result), void *userdata);
     void        (*on_result)(client_t *client, void *userdata, auth_result result);
     void         *userdata;
@@ -89,11 +88,11 @@ struct auth_tag
     auth_result (*release_client)(auth_client *auth_user);
 
     /* auth state-specific free call */
-    void (*free)(struct auth_tag *self);
+    void (*free)(auth_t *self);
 
-    auth_result (*adduser)(struct auth_tag *auth, const char *username, const char *password);
-    auth_result (*deleteuser)(struct auth_tag *auth, const char *username);
-    auth_result (*listuser)(struct auth_tag *auth, xmlNodePtr srcnode);
+    auth_result (*adduser)(auth_t *auth, const char *username, const char *password);
+    auth_result (*deleteuser)(auth_t *auth, const char *username);
+    auth_result (*listuser)(auth_t *auth, xmlNodePtr srcnode);
 
     mutex_t lock;
     int running;
diff --git a/src/auth_static.c b/src/auth_static.c
index 66528bfe..c5ca6880 100644
--- a/src/auth_static.c
+++ b/src/auth_static.c
@@ -18,6 +18,7 @@
 #include <string.h>
 
 #include "auth.h"
+#include "cfgfile.h"
 #include "client.h"
 
 #include "logging.h"
diff --git a/src/auth_url.c b/src/auth_url.c
index 0b2bb86d..7ce87c24 100644
--- a/src/auth_url.c
+++ b/src/auth_url.c
@@ -72,6 +72,7 @@
 #include "source.h"
 #include "client.h"
 #include "cfgfile.h"
+#include "connection.h"
 #include "common/httpp/httpp.h"
 
 #include "logging.h"
diff --git a/src/cfgfile.c b/src/cfgfile.c
index fcf5b183..0b6c7b27 100644
--- a/src/cfgfile.c
+++ b/src/cfgfile.c
@@ -27,15 +27,13 @@
 #include <libxml/parser.h>
 
 #include "common/thread/thread.h"
+
 #include "cfgfile.h"
 #include "global.h"
-#include "refbuf.h"
-#include "client.h"
 #include "logging.h"
 #include "util.h"
 #include "auth.h"
 #include "event.h"
-#include "tls.h"
 
 /* for config_reread_config() */
 #include "yp.h"
@@ -43,6 +41,7 @@
 #include "stats.h"
 #include "connection.h"
 #include "main.h"
+#include "slave.h"
 
 #define CATMODULE                       "CONFIG"
 #define CONFIG_DEFAULT_LOCATION         "Earth"
diff --git a/src/cfgfile.h b/src/cfgfile.h
index cdeb4c92..9705bbb7 100644
--- a/src/cfgfile.h
+++ b/src/cfgfile.h
@@ -22,37 +22,13 @@
 
 #define MAX_YP_DIRECTORIES 25
 
-struct _mount_proxy;
-
 #include <libxml/tree.h>
 #include "common/thread/thread.h"
 #include "common/avl/avl.h"
-#include "slave.h"
-#include "connection.h"
+#include "icecasttypes.h"
 
 #define XMLSTR(str) ((xmlChar *)(str)) 
 
-typedef enum _operation_mode {
- /* Default operation mode. may depend on context */
- OMODE_DEFAULT = 0,
- /* The normal mode. */
- OMODE_NORMAL,
- /* Mimic some of the behavior of older versions.
-  * This mode should only be used in transition to normal mode,
-  * e.g. to give some clients time to upgrade to new API.
-  */
- OMODE_LEGACY,
- /* The struct mode includes some behavior for future versions
-  * that can for some reason not yet be used in the normal mode
-  * e.g. because it may break interfaces in some way.
-  * New applications should test against this mode and developer
-  * of software interacting with Icecast on an API level should
-  * have a look for strict mode behavior to avoid random breakage
-  * with newer versions of Icecast.
-  */
- OMODE_STRICT
-} operation_mode;
-
 typedef enum _http_header_type {
  /* static: headers are passed as is to the client. */
  HTTP_HEADER_TYPE_STATIC
@@ -79,12 +55,12 @@ typedef struct ice_config_dir_tag {
     struct ice_config_dir_tag *next;
 } ice_config_dir_t;
 
-typedef struct _config_options {
+struct _config_options {
     char *type;
     char *name;
     char *value;
-    struct _config_options *next;
-} config_options_t;
+    config_options_t *next;
+};
 
 typedef enum _mount_type {
  MOUNT_TYPE_NORMAL,
@@ -184,7 +160,7 @@ typedef struct _config_tls_context {
     char *cipher_list;
 } config_tls_context_t;
 
-typedef struct ice_config_tag {
+struct ice_config_tag {
     char *config_filename;
 
     char *location;
@@ -260,7 +236,7 @@ typedef struct ice_config_tag {
     int yp_url_timeout[MAX_YP_DIRECTORIES];
     int yp_touch_interval[MAX_YP_DIRECTORIES];
     int num_yp_directories;
-} ice_config_t;
+};
 
 typedef struct {
     rwlock_t config_lock;
diff --git a/src/client.c b/src/client.c
index a8863246..d80edcdf 100644
--- a/src/client.c
+++ b/src/client.c
@@ -42,6 +42,7 @@
 #include "logging.h"
 
 #include "util.h"
+#include "acl.h"
 
 /* for ADMIN_COMMAND_ERROR */
 #include "admin.h"
diff --git a/src/client.h b/src/client.h
index c4bab286..aa9318b0 100644
--- a/src/client.h
+++ b/src/client.h
@@ -19,17 +19,13 @@
 #ifndef __CLIENT_H__
 #define __CLIENT_H__
 
-typedef struct _client_tag client_t;
-
-#include "errors.h"
-#include "connection.h"
-#include "refbuf.h"
-#include "acl.h"
-#include "cfgfile.h"
-#include "admin.h"
 #include "common/httpp/httpp.h"
 #include "common/httpp/encoding.h"
 
+#include "icecasttypes.h"
+#include "errors.h"
+#include "refbuf.h"
+
 #define CLIENT_DEFAULT_ADMIN_FORMAT                     ADMIN_FORMAT_TRANSFORMED
 
 typedef enum _protocol_tag {
@@ -96,19 +92,19 @@ struct _client_tag {
     unsigned int pos;
 
     /* auth used for this client */
-    struct auth_tag *auth;
+    auth_t *auth;
 
     /* Format-handler-specific data for this client */
     void *format_data;
 
     /* function to call to release format specific resources */
-    void (*free_client_data)(struct _client_tag *client);
+    void (*free_client_data)(client_t *client);
 
     /* write out data associated with client */
-    int (*write_to_client)(struct _client_tag *client);
+    int (*write_to_client)(client_t *client);
 
     /* function to check if refbuf needs updating */
-    int (*check_buffer)(struct source_tag *source, struct _client_tag *client);
+    int (*check_buffer)(source_t *source, client_t *client);
 };
 
 int client_create (client_t **c_ptr, connection_t *con, http_parser_t *parser);
diff --git a/src/compat.h b/src/compat.h
index c876601e..be12e2f2 100644
--- a/src/compat.h
+++ b/src/compat.h
@@ -20,6 +20,10 @@
  * Solaris.
  */
 
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
 #ifdef HAVE_UNISTD_H
 #include <unistd.h>
 #endif
diff --git a/src/connection.c b/src/connection.c
index 734aeece..50b79aeb 100644
--- a/src/connection.c
+++ b/src/connection.c
@@ -33,34 +33,30 @@
 #include <winsock2.h>
 #endif
 
-#include "compat.h"
-
 #include "common/thread/thread.h"
 #include "common/avl/avl.h"
 #include "common/net/sock.h"
 #include "common/httpp/httpp.h"
 
+#include "compat.h"
+#include "connection.h"
 #include "cfgfile.h"
 #include "global.h"
 #include "util.h"
-#include "connection.h"
 #include "refbuf.h"
 #include "client.h"
 #include "errors.h"
 #include "stats.h"
 #include "logging.h"
-#include "xslt.h"
 #include "fserve.h"
-#include "sighandler.h"
+#include "slave.h"
 
-#include "yp.h"
 #include "source.h"
-#include "format.h"
-#include "format_mp3.h"
 #include "admin.h"
 #include "auth.h"
 #include "matchfile.h"
 #include "tls.h"
+#include "acl.h"
 
 #define CATMODULE "connection"
 
@@ -144,7 +140,7 @@ void connection_shutdown(void)
     _initialized = 0;
 }
 
-void connection_reread_config(struct ice_config_tag *config)
+void connection_reread_config(ice_config_t *config)
 {
     get_tls_certificate(config);
 }
diff --git a/src/connection.h b/src/connection.h
index 271b0dea..3a989d7e 100644
--- a/src/connection.h
+++ b/src/connection.h
@@ -19,30 +19,12 @@
 
 #include "tls.h"
 
+#include "icecasttypes.h"
 #include "compat.h"
-#include "common/httpp/httpp.h"
 #include "common/thread/thread.h"
 #include "common/net/sock.h"
 
-struct _client_tag;
-struct source_tag;
-struct ice_config_tag;
-
-typedef enum _tlsmode_tag {
-    /* no TLS is used at all */
-    ICECAST_TLSMODE_DISABLED = 0,
-    /* TLS mode is to be detected */
-    ICECAST_TLSMODE_AUTO,
-    /* Like ICECAST_TLSMODE_AUTO but enforces TLS */
-    ICECAST_TLSMODE_AUTO_NO_PLAIN,
-    /* TLS via HTTP Upgrade:-header [RFC2817] */
-    ICECAST_TLSMODE_RFC2817,
-    /* TLS for transport layer like HTTPS [RFC2818] does */
-    ICECAST_TLSMODE_RFC2818
-} tlsmode_t;
-
-typedef struct connection_tag
-{
+struct connection_tag {
     unsigned long id;
 
     time_t con_time;
@@ -55,20 +37,20 @@ typedef struct connection_tag
 
     tlsmode_t tlsmode;
     tls_t *tls;
-    int (*send)(struct connection_tag *handle, const void *buf, size_t len);
-    int (*read)(struct connection_tag *handle, void *buf, size_t len);
+    int (*send)(connection_t *handle, const void *buf, size_t len);
+    int (*read)(connection_t *handle, void *buf, size_t len);
 
     char *ip;
-} connection_t;
+};
 
 void connection_initialize(void);
 void connection_shutdown(void);
-void connection_reread_config(struct ice_config_tag *config);
+void connection_reread_config(ice_config_t *config);
 void connection_accept_loop(void);
-int connection_setup_sockets(struct ice_config_tag *config);
+int connection_setup_sockets(ice_config_t *config);
 void connection_close(connection_t *con);
 connection_t *connection_create(sock_t sock, sock_t serversock, char *ip);
-int connection_complete_source(struct source_tag *source, int response);
+int connection_complete_source(source_t *source, int response);
 void connection_queue(connection_t *con);
 void connection_uses_tls(connection_t *con);
 
diff --git a/src/curl.c b/src/curl.c
index 95f2740e..7d44fc8d 100644
--- a/src/curl.c
+++ b/src/curl.c
@@ -11,6 +11,7 @@
 #endif
 
 #include "curl.h"
+#include "cfgfile.h"
 
 #include "logging.h"
 #define CATMODULE "curl"
diff --git a/src/event.c b/src/event.c
index 254998d9..17b1aae8 100644
--- a/src/event.c
+++ b/src/event.c
@@ -20,6 +20,9 @@
 #include "event_url.h"
 #include "logging.h"
 #include "admin.h"
+#include "connection.h"
+#include "client.h"
+#include "cfgfile.h"
 
 #define CATMODULE "event"
 
diff --git a/src/event.h b/src/event.h
index aafc9fc8..3ef2b497 100644
--- a/src/event.h
+++ b/src/event.h
@@ -9,18 +9,13 @@
 #ifndef __EVENT_H__
 #define __EVENT_H__
 
-#ifdef HAVE_CONFIG_H
-#include <config.h>
-#endif
-
 #include <libxml/xmlmemory.h>
 #include <libxml/parser.h>
 #include <libxml/tree.h>
-#include "common/httpp/httpp.h"
 
-#include "cfgfile.h"
-#include "client.h"
-#include "source.h"
+#include "common/thread/thread.h"
+
+#include "icecasttypes.h"
 
 /* implemented */
 #define EVENT_TYPE_LOG  "log"
diff --git a/src/event_exec.c b/src/event_exec.c
index 488c88a9..43da2568 100644
--- a/src/event_exec.c
+++ b/src/event_exec.c
@@ -22,6 +22,7 @@
 
 #include "event.h"
 #include "global.h"
+#include "source.h"
 #include "logging.h"
 #define CATMODULE "event_exec"
 
diff --git a/src/event_log.c b/src/event_log.c
index 37905c76..36f194d2 100644
--- a/src/event_log.c
+++ b/src/event_log.c
@@ -13,6 +13,8 @@
 #include <string.h>
 
 #include "event.h"
+#include "util.h"
+#include "cfgfile.h"
 #include "logging.h"
 #define CATMODULE "event_log"
 
diff --git a/src/event_url.c b/src/event_url.c
index a8078dbd..7176209a 100644
--- a/src/event_url.c
+++ b/src/event_url.c
@@ -14,6 +14,8 @@
 
 #include "curl.h"
 #include "event.h"
+#include "cfgfile.h"
+#include "util.h"
 #include "logging.h"
 #define CATMODULE "event_url"
 
diff --git a/src/format.h b/src/format.h
index a5733644..aa94aa68 100644
--- a/src/format.h
+++ b/src/format.h
@@ -20,13 +20,12 @@
 
 #include <vorbis/codec.h>
 
+#include "icecasttypes.h"
 #include "client.h"
 #include "refbuf.h"
+#include "cfgfile.h"
 #include "common/httpp/httpp.h"
 
-struct source_tag;
-struct _mount_proxy;
-
 typedef enum _format_type_tag
 {
     FORMAT_ERROR, /* No format, source not processable */
@@ -47,13 +46,13 @@ typedef struct _format_plugin_tag
     uint64_t    read_bytes;
     uint64_t    sent_bytes;
 
-    refbuf_t *(*get_buffer)(struct source_tag *);
+    refbuf_t *(*get_buffer)(source_t *);
     int (*write_buf_to_client)(client_t *client);
-    void (*write_buf_to_file)(struct source_tag *source, refbuf_t *refbuf);
-    int (*create_client_data)(struct source_tag *source, client_t *client);
+    void (*write_buf_to_file)(source_t *source, refbuf_t *refbuf);
+    int (*create_client_data)(source_t *source, client_t *client);
     void (*set_tag)(struct _format_plugin_tag *plugin, const char *tag, const char *value, const char *charset);
     void (*free_plugin)(struct _format_plugin_tag *self);
-    void (*apply_settings)(client_t *client, struct _format_plugin_tag *format, struct _mount_proxy *mount);
+    void (*apply_settings)(client_t *client, struct _format_plugin_tag *format, mount_proxy *mount);
 
     /* meta data */
     vorbis_comment vc;
@@ -64,16 +63,16 @@ typedef struct _format_plugin_tag
 
 format_type_t format_get_type(const char *contenttype);
 char *format_get_mimetype(format_type_t type);
-int format_get_plugin(format_type_t type, struct source_tag *source);
+int format_get_plugin(format_type_t type, source_t *source);
 
 int format_generic_write_to_client (client_t *client);
-int format_advance_queue (struct source_tag *source, client_t *client);
-int format_check_http_buffer (struct source_tag *source, client_t *client);
-int format_check_file_buffer (struct source_tag *source, client_t *client);
+int format_advance_queue (source_t *source, client_t *client);
+int format_check_http_buffer (source_t *source, client_t *client);
+int format_check_file_buffer (source_t *source, client_t *client);
 
 
 void format_send_general_headers(format_plugin_t *format, 
-        struct source_tag *source, client_t *client);
+        source_t *source, client_t *client);
 
 void format_set_vorbiscomment(format_plugin_t *plugin, const char *tag, const char *value);
 
diff --git a/src/format_mp3.c b/src/format_mp3.c
index 4fa9fbd8..dae620c6 100644
--- a/src/format_mp3.c
+++ b/src/format_mp3.c
@@ -32,6 +32,7 @@
 #include "refbuf.h"
 #include "source.h"
 #include "client.h"
+#include "connection.h"
 
 #include "stats.h"
 #include "format.h"
@@ -55,7 +56,7 @@ static refbuf_t *mp3_get_no_meta (source_t *source);
 static int  format_mp3_create_client_data (source_t *source, client_t *client);
 static void free_mp3_client_data (client_t *client);
 static int format_mp3_write_buf_to_client(client_t *client);
-static void write_mp3_to_file (struct source_tag *source, refbuf_t *refbuf);
+static void write_mp3_to_file (source_t *source, refbuf_t *refbuf);
 static void mp3_set_tag (format_plugin_t *plugin, const char *tag, const char *in_value, const char *charset);
 static void format_mp3_apply_settings(client_t *client, format_plugin_t *format, mount_proxy *mount);
 
@@ -715,7 +716,7 @@ static void free_mp3_client_data (client_t *client)
 }
 
 
-static void write_mp3_to_file (struct source_tag *source, refbuf_t *refbuf)
+static void write_mp3_to_file (source_t *source, refbuf_t *refbuf)
 {
     if (refbuf->len == 0)
         return;
diff --git a/src/format_ogg.c b/src/format_ogg.c
index d905bfce..605279f8 100644
--- a/src/format_ogg.c
+++ b/src/format_ogg.c
@@ -60,7 +60,7 @@ static void format_ogg_free_plugin(format_plugin_t *plugin);
 static int create_ogg_client_data(source_t *source, client_t *client);
 static void free_ogg_client_data(client_t *client);
 
-static void write_ogg_to_file(struct source_tag *source, refbuf_t *refbuf);
+static void write_ogg_to_file(source_t *source, refbuf_t *refbuf);
 static refbuf_t *ogg_get_buffer(source_t *source);
 static int write_buf_to_client(client_t *client);
 
@@ -563,7 +563,7 @@ static int write_buf_to_client(client_t *client)
 }
 
 
-static int write_ogg_data (struct source_tag *source, refbuf_t *refbuf)
+static int write_ogg_data (source_t *source, refbuf_t *refbuf)
 {
     int ret = 1;
 
@@ -578,7 +578,7 @@ static int write_ogg_data (struct source_tag *source, refbuf_t *refbuf)
 }
 
 
-static void write_ogg_to_file (struct source_tag *source, refbuf_t *refbuf)
+static void write_ogg_to_file (source_t *source, refbuf_t *refbuf)
 {
     ogg_state_t *ogg_info = source->format->_state;
 
diff --git a/src/fserve.c b/src/fserve.c
index 15b6a50a..75efe38c 100644
--- a/src/fserve.c
+++ b/src/fserve.c
@@ -47,6 +47,8 @@
 #include "common/httpp/httpp.h"
 #include "common/net/sock.h"
 
+#include "fserve.h"
+#include "compat.h"
 #include "connection.h"
 #include "global.h"
 #include "refbuf.h"
@@ -58,9 +60,6 @@
 #include "cfgfile.h"
 #include "util.h"
 #include "admin.h"
-#include "compat.h"
-
-#include "fserve.h"
 
 #undef CATMODULE
 #define CATMODULE "fserve"
diff --git a/src/fserve.h b/src/fserve.h
index a5035100..d2408955 100644
--- a/src/fserve.h
+++ b/src/fserve.h
@@ -14,7 +14,8 @@
 #define __FSERVE_H__
 
 #include <stdio.h>
-#include "cfgfile.h"
+
+#include "icecasttypes.h"
 
 typedef void (*fserve_callback_t)(client_t *, void *);
 
diff --git a/src/global.h b/src/global.h
index 12013a63..c7e6633a 100644
--- a/src/global.h
+++ b/src/global.h
@@ -22,8 +22,8 @@
 
 #include "common/thread/thread.h"
 #include "common/avl/avl.h"
-#include "slave.h"
 #include "common/net/sock.h"
+#include "icecasttypes.h"
 
 typedef struct ice_global_tag
 {
@@ -38,9 +38,9 @@ typedef struct ice_global_tag
 
     avl_tree *source_tree;
     /* for locally defined relays */
-    struct _relay_server *relays;
+    relay_server *relays;
     /* relays retrieved from master */
-    struct _relay_server *master_relays;
+    relay_server *master_relays;
 
     cond_t shutdown_cond;
 } ice_global_t;
diff --git a/src/icecasttypes.h b/src/icecasttypes.h
new file mode 100644
index 00000000..941c13f7
--- /dev/null
+++ b/src/icecasttypes.h
@@ -0,0 +1,91 @@
+/* Icecast
+ *
+ * This program is distributed under the GNU General Public License, version 2.
+ * A copy of this license is included with this source.
+ *
+ * Copyright 2018,      Philipp "ph3-der-loewe" Schafft <lion@lion.leolix.org>,
+ */
+
+#ifndef __ICECASTTYPES_H__
+#define __ICECASTTYPES_H__
+
+#include "compat.h"
+
+/* ---[ client.[ch] ]--- */
+
+typedef struct _client_tag client_t;
+
+/* ---[ source.[ch] ]--- */
+
+typedef struct source_tag source_t;
+
+/* ---[ admin.[ch] ]--- */
+
+/* Command IDs */
+typedef int32_t admin_command_id_t;
+
+/* formats */
+typedef enum {
+    ADMIN_FORMAT_AUTO,
+    ADMIN_FORMAT_RAW,
+    ADMIN_FORMAT_TRANSFORMED,
+    ADMIN_FORMAT_PLAINTEXT
+} admin_format_t;
+
+/* ---[ acl.[ch] ]--- */
+
+typedef struct acl_tag acl_t;
+
+/* ---[ auth.[ch] ]--- */
+
+typedef struct auth_tag auth_t;
+
+/* ---[ cfgfile.[ch] ]--- */
+
+typedef struct ice_config_tag ice_config_t;
+
+typedef struct _config_options config_options_t;
+
+typedef enum _operation_mode {
+ /* Default operation mode. may depend on context */
+ OMODE_DEFAULT = 0,
+ /* The normal mode. */
+ OMODE_NORMAL,
+ /* Mimic some of the behavior of older versions.
+  * This mode should only be used in transition to normal mode,
+  * e.g. to give some clients time to upgrade to new API.
+  */
+ OMODE_LEGACY,
+ /* The struct mode includes some behavior for future versions
+  * that can for some reason not yet be used in the normal mode
+  * e.g. because it may break interfaces in some way.
+  * New applications should test against this mode and developer
+  * of software interacting with Icecast on an API level should
+  * have a look for strict mode behavior to avoid random breakage
+  * with newer versions of Icecast.
+  */
+ OMODE_STRICT
+} operation_mode;
+
+/* ---[ connection.[ch] ]--- */
+
+typedef struct connection_tag connection_t;
+
+typedef enum {
+    /* no TLS is used at all */
+    ICECAST_TLSMODE_DISABLED = 0,
+    /* TLS mode is to be detected */
+    ICECAST_TLSMODE_AUTO,
+    /* Like ICECAST_TLSMODE_AUTO but enforces TLS */
+    ICECAST_TLSMODE_AUTO_NO_PLAIN,
+    /* TLS via HTTP Upgrade:-header [RFC2817] */
+    ICECAST_TLSMODE_RFC2817,
+    /* TLS for transport layer like HTTPS [RFC2818] does */
+    ICECAST_TLSMODE_RFC2818
+} tlsmode_t;
+
+/* ---[ slave.[ch] ]--- */
+
+typedef struct _relay_server relay_server;
+
+#endif
diff --git a/src/logging.c b/src/logging.c
index dd78cb9f..6ae0054a 100644
--- a/src/logging.c
+++ b/src/logging.c
@@ -22,13 +22,13 @@
 #include "common/thread/thread.h"
 #include "common/httpp/httpp.h"
 
+#include "logging.h"
 #include "connection.h"
 #include "refbuf.h"
 #include "client.h"
 
 #include "compat.h"
 #include "cfgfile.h"
-#include "logging.h"
 #include "util.h"
 
 #ifdef _WIN32
diff --git a/src/logging.h b/src/logging.h
index 3a9ebc2e..36dee18d 100644
--- a/src/logging.h
+++ b/src/logging.h
@@ -14,10 +14,10 @@
 #ifndef __LOGGING_H__
 #define __LOGGING_H__
 
-#include "cfgfile.h"
-#include "client.h"
 #include "common/log/log.h"
 
+#include "icecasttypes.h"
+
 /* declare the global log descriptors */
 
 extern int errorlog;
diff --git a/src/main.c b/src/main.c
index e8a6282e..ce8af228 100644
--- a/src/main.c
+++ b/src/main.c
@@ -45,7 +45,6 @@
 #endif
 
 #include "common/thread/thread.h"
-#include "common/avl/avl.h"
 #include "common/net/sock.h"
 #include "common/net/resolver.h"
 #include "common/httpp/httpp.h"
diff --git a/src/matchfile.c b/src/matchfile.c
index 387f7fab..5e3176a5 100644
--- a/src/matchfile.c
+++ b/src/matchfile.c
@@ -19,10 +19,11 @@
 #include <sys/stat.h>
 #include <unistd.h>
 
+#include "common/avl/avl.h"
+
 #include "matchfile.h"
 #include "logging.h"
 #include "util.h" /* for MAX_LINE_LEN and get_line() */
-#include "common/avl/avl.h"
 #define CATMODULE "matchfile"
 
 struct matchfile_tag {
diff --git a/src/slave.c b/src/slave.c
index c42441e2..e5ede252 100644
--- a/src/slave.c
+++ b/src/slave.c
@@ -42,6 +42,7 @@
 #include "common/net/sock.h"
 #include "common/httpp/httpp.h"
 
+#include "slave.h"
 #include "cfgfile.h"
 #include "global.h"
 #include "util.h"
diff --git a/src/slave.h b/src/slave.h
index d8ff50de..b8df836d 100644
--- a/src/slave.h
+++ b/src/slave.h
@@ -14,8 +14,9 @@
 #define __SLAVE_H__
 
 #include "common/thread/thread.h"
+#include "icecasttypes.h"
 
-typedef struct _relay_server {
+struct _relay_server {
     char *server;
     int port;
     char *mount;
@@ -23,16 +24,15 @@ typedef struct _relay_server {
     char *password;
     char *localmount;
     char *bind;
-    struct source_tag *source;
+    source_t *source;
     int mp3metadata;
     int on_demand;
     int running;
     int cleanup;
     time_t start;
     thread_type *thread;
-    struct _relay_server *next;
-} relay_server;
-
+    relay_server *next;
+};
 
 void slave_initialize(void);
 void slave_shutdown(void);
diff --git a/src/source.c b/src/source.c
index b7ace96a..ef8aa347 100644
--- a/src/source.c
+++ b/src/source.c
@@ -42,8 +42,9 @@
 #include "common/thread/thread.h"
 #include "common/avl/avl.h"
 #include "common/httpp/httpp.h"
-#include "common/net/sock.h"
 
+#include "source.h"
+#include "compat.h"
 #include "connection.h"
 #include "global.h"
 #include "refbuf.h"
@@ -53,12 +54,12 @@
 #include "logging.h"
 #include "cfgfile.h"
 #include "util.h"
-#include "source.h"
 #include "format.h"
 #include "fserve.h"
 #include "auth.h"
 #include "event.h"
-#include "compat.h"
+#include "slave.h"
+#include "acl.h"
 
 #undef CATMODULE
 #define CATMODULE "source"
diff --git a/src/source.h b/src/source.h
index c34d99a3..adb5f835 100644
--- a/src/source.h
+++ b/src/source.h
@@ -14,16 +14,16 @@
 #ifndef __SOURCE_H__
 #define __SOURCE_H__
 
-typedef struct source_tag source_t;
+#include <stdio.h>
 
-#include "cfgfile.h"
+#include "common/thread/thread.h"
+#include "common/httpp/httpp.h"
+
+#include "icecasttypes.h"
 #include "yp.h"
 #include "util.h"
 #include "format.h"
 #include "playlist.h"
-#include "common/thread/thread.h"
-
-#include <stdio.h>
 
 struct source_tag {
     mutex_t lock;
diff --git a/src/stats.c b/src/stats.c
index a77d82b1..79c82798 100644
--- a/src/stats.c
+++ b/src/stats.c
@@ -30,14 +30,13 @@
 #include "common/httpp/httpp.h"
 #include "common/net/sock.h"
 
+#include "stats.h"
 #include "connection.h"
-
 #include "source.h"
 #include "global.h"
 #include "refbuf.h"
 #include "client.h"
 #include "admin.h"
-#include "stats.h"
 #include "xslt.h"
 #include "util.h"
 #include "auth.h"
diff --git a/src/stats.h b/src/stats.h
index ae70318c..3ec72214 100644
--- a/src/stats.h
+++ b/src/stats.h
@@ -13,14 +13,13 @@
 #ifndef __STATS_H__
 #define __STATS_H__
 
-#include "cfgfile.h"
-#include "connection.h"
-#include "common/httpp/httpp.h"
-#include "client.h"
 #include <libxml/xmlmemory.h>
 #include <libxml/parser.h>
 #include <libxml/tree.h>
 
+#include "icecasttypes.h"
+#include "cfgfile.h"
+#include "refbuf.h"
 
 typedef struct _stats_node_tag
 {
diff --git a/src/tls.c b/src/tls.c
index 360e9280..94922f88 100644
--- a/src/tls.c
+++ b/src/tls.c
@@ -14,6 +14,11 @@
 #include <config.h>
 #endif
 
+#ifdef HAVE_OPENSSL
+#include <openssl/ssl.h>
+#include <openssl/err.h>
+#endif
+
 #include <stdlib.h>
 #include <strings.h>
 
diff --git a/src/tls.h b/src/tls.h
index 50edf047..4ba505ac 100644
--- a/src/tls.h
+++ b/src/tls.h
@@ -9,11 +9,6 @@
 #ifndef __TLS_H__
 #define __TLS_H__
 
-#ifdef HAVE_OPENSSL
-#include <openssl/ssl.h>
-#include <openssl/err.h>
-#endif
-
 #include "common/net/sock.h"
 
 /* Do we have TLS Support? */
diff --git a/src/util.c b/src/util.c
index abc2aaad..da1675c3 100644
--- a/src/util.c
+++ b/src/util.c
@@ -41,12 +41,12 @@
 #include "common/net/sock.h"
 #include "common/thread/thread.h"
 
-#include "cfgfile.h"
+#include "util.h"
 #include "compat.h"
+#include "cfgfile.h"
 #include "refbuf.h"
 #include "connection.h"
 #include "client.h"
-#include "util.h"
 #include "source.h"
 #include "admin.h"
 
@@ -664,7 +664,7 @@ ssize_t util_http_build_header(char * out, size_t len, ssize_t offset,
         int status, const char * statusmsg,
         const char * contenttype, const char * charset,
         const char * datablock,
-        struct source_tag * source, struct _client_tag * client) {
+        source_t * source, client_t * client) {
     const char * http_version = "1.0";
     ice_config_t *config;
     time_t now;
diff --git a/src/util.h b/src/util.h
index cdc30fbe..299e0123 100644
--- a/src/util.h
+++ b/src/util.h
@@ -17,6 +17,9 @@
 /* for FILE* */
 #include <stdio.h>
 
+#include "common/net/sock.h"
+#include "icecasttypes.h"
+
 #define UNKNOWN_CONTENT 0
 #define XSLT_CONTENT    1
 #define HTML_CONTENT    2
@@ -78,15 +81,13 @@ char *util_url_escape(const char *src);
  * If datablock is NULL no end-of-header nor any data is appended.
  * Returns the number of bytes written or -1 on error.
  */
-struct source_tag; /* use forward decleration so we do not need to
-                    * include <source.h> that would cause other conflicts. */
 ssize_t util_http_build_header(char * out, size_t len, ssize_t offset,
         int cache,
         int status, const char * statusmsg,
         const char * contenttype, const char * charset,
         const char * datablock,
-        struct source_tag * source,
-        struct _client_tag * client);
+        source_t * source,
+        client_t * client);
 
 const char *util_http_select_best(const char *input, const char *first, ...);
 
diff --git a/src/xslt.c b/src/xslt.c
index 09af35b4..8dd35969 100644
--- a/src/xslt.c
+++ b/src/xslt.c
@@ -46,13 +46,10 @@
 #include "common/httpp/httpp.h"
 #include "common/net/sock.h"
 
-#include "connection.h"
-
-#include "global.h"
+#include "xslt.h"
 #include "refbuf.h"
 #include "client.h"
 #include "errors.h"
-#include "config.h"
 #include "stats.h"
 #include "fserve.h"
 #include "util.h"
diff --git a/src/xslt.h b/src/xslt.h
index 841ceb20..97e771bd 100644
--- a/src/xslt.h
+++ b/src/xslt.h
@@ -11,28 +11,10 @@
  */
 
 #include <libxml/xmlmemory.h>
-#include <libxml/debugXML.h>
-#include <libxml/HTMLtree.h>
-#include <libxml/xmlIO.h>
-#include <libxslt/xslt.h>
-#include <libxslt/xsltInternals.h>
-#include <libxslt/transform.h>
-#include <libxslt/xsltutils.h>
-
-
-#include "common/thread/thread.h"
-#include "common/avl/avl.h"
-#include "common/httpp/httpp.h"
-#include "common/net/sock.h"
-
-
-#include "connection.h"
-
-#include "global.h"
-#include "refbuf.h"
-#include "client.h"
-#include "stats.h"
+#include <libxml/parser.h>
+#include <libxml/tree.h>
 
+#include "icecasttypes.h"
 
 void xslt_transform(xmlDocPtr doc, const char *xslfilename, client_t *client);
 void xslt_initialize(void);
diff --git a/src/yp.c b/src/yp.c
index 3effbe9d..8954f5a5 100644
--- a/src/yp.c
+++ b/src/yp.c
@@ -21,13 +21,10 @@
 
 #include "common/thread/thread.h"
 
+#include "yp.h"
 #include "global.h"
 #include "curl.h"
-#include "connection.h"
-#include "refbuf.h"
-#include "client.h"
 #include "logging.h"
-#include "format.h"
 #include "source.h"
 #include "cfgfile.h"
 #include "stats.h"
diff --git a/src/yp.h b/src/yp.h
index 040ebc18..40d43844 100644
--- a/src/yp.h
+++ b/src/yp.h
@@ -14,6 +14,8 @@
 #ifndef __YP_H__
 #define __YP_H__
 
+#include "icecasttypes.h"
+
 #define  YP_SERVER_NAME         1
 #define  YP_SERVER_DESC         2
 #define  YP_SERVER_GENRE        3