diff --git a/src/include/sdk.h b/src/include/sdk.h
new file mode 100644
index 0000000..2a7ba6c
--- /dev/null
+++ b/src/include/sdk.h
@@ -0,0 +1,101 @@
+#ifndef _SDK_H
+#define _SDK_H
+
+/*
+ * cl_enginefunc_t:
+ *   sdk/cl_dll/cl_dll.h:40 -> sdk/engine/cdll_int.h:164 ---+
+ *   sdk/engine/APIProxy.h:358-494    <---------------------+
+ */
+#include "../sdk/cl_dll/wrect.h"
+#include "../sdk/cl_dll/cl_dll.h"
+
+#include "../sdk/common/event_api.h"
+#include "../sdk/pm_shared/pm_defs.h"
+#include "../sdk/common/cvardef.h"
+#include "../sdk/common/mathlib.h"
+#include "../sdk/common/r_studioint.h"
+#include "../sdk/cl_dll/global_consts.h"
+#include "../sdk/common/com_model.h"
+#include "../sdk/engine/studio.h"
+#include "../sdk/common/triangleapi.h"
+#include "../sdk/common/screenfade.h"
+#include "../sdk/common/net_api.h"
+#include "../sdk/common/parsemsg.h"
+
+typedef struct cl_clientfuncs_s {
+    int (*Initialize)(cl_enginefunc_t* pEnginefuncs, int iVersion);
+    void (*HUD_Init)(void);
+    int (*HUD_VidInit)(void);
+    int (*HUD_Redraw)(float time, int intermission);
+    int (*HUD_UpdateClientData)(client_data_t* pcldata, float flTime);
+    void (*HUD_Reset)(void);
+    void (*HUD_PlayerMove)(struct playermove_s* ppmove, int server);
+    void (*HUD_PlayerMoveInit)(struct playermove_s* ppmove);
+    char (*HUD_PlayerMoveTexture)(char* name);
+    void (*IN_ActivateMouse)(void);
+    void (*IN_DeactivateMouse)(void);
+    void (*IN_MouseEvent)(int mstate);
+    void (*IN_ClearStates)(void);
+    void (*IN_Accumulate)(void);
+    void (*CL_CreateMove)(float frametime, struct usercmd_s* cmd, int active);
+    int (*CL_IsThirdPerson)(void);
+    void (*CL_CameraOffset)(float* ofs);
+    struct kbutton_s* (*KB_Find)(const char* name);
+    void (*CAM_Think)(void);
+    void (*V_CalcRefdef)(struct ref_params_s* pparams);
+    int (*HUD_AddEntity)(int type, struct cl_entity_s* ent,
+                         const char* modelname);
+
+    void (*HUD_CreateEntities)(void);
+    void (*HUD_DrawNormalTriangles)(void);
+    void (*HUD_DrawTransparentTriangles)(void);
+    void (*HUD_StudioEvent)(const struct mstudioevent_s* event,
+                            const struct cl_entity_s* entity);
+
+    void (*HUD_PostRunCmd)(struct local_state_s* from, struct local_state_s* to,
+                           struct usercmd_s* cmd, int runfuncs, double time,
+                           unsigned int random_seed);
+
+    void (*HUD_Shutdown)(void);
+    void (*HUD_TxferLocalOverrides)(struct entity_state_s* state,
+                                    const struct clientdata_s* client);
+
+    void (*HUD_ProcessPlayerState)(struct entity_state_s* dst,
+                                   const struct entity_state_s* src);
+
+    void (*HUD_TxferPredictionData)(struct entity_state_s* ps,
+                                    const struct entity_state_s* pps,
+                                    struct clientdata_s* pcd,
+                                    const struct clientdata_s* ppcd,
+                                    struct weapon_data_s* wd,
+                                    const struct weapon_data_s* pwd);
+
+    void (*Demo_ReadBuffer)(int size, unsigned char* buffer);
+    int (*HUD_ConnectionlessPacket)(struct netadr_s* net_from, const char* args,
+                                    char* response_buffer,
+                                    int* response_buffer_size);
+
+    int (*HUD_GetHullBounds)(int hullnumber, float* mins, float* maxs);
+    void (*HUD_Frame)(double time);
+    int (*HUD_Key_Event)(int down, int keynum, const char* pszCurrentBinding);
+    void (*HUD_TempEntUpdate)(
+      double frametime, double client_time, double cl_gravity,
+      struct tempent_s** ppTempEntFree, struct tempent_s** ppTempEntActive,
+      int (*Callback_AddVisibleEntity)(struct cl_entity_s* pEntity),
+      void (*Callback_TempEntPlaySound)(struct tempent_s* pTemp, float damp));
+
+    struct cl_entity_s* (*HUD_GetUserEntity)(int index);
+    int (*HUD_VoiceStatus)(int entindex, qboolean bTalking);
+    int (*HUD_DirectorMessage)(unsigned char command, unsigned int firstObject,
+                               unsigned int secondObject, unsigned int flags);
+
+    int (*HUD_GetStudioModelInterface)(
+      int version, struct r_studio_interface_s** ppinterface,
+      struct engine_studio_api_s* pstudio);
+
+    void (*HUD_CHATINPUTPOSITION_FUNCTION)(int* x, int* y);
+    int (*HUD_GETPLAYERTEAM_FUNCTION)(int iplayer);
+    void (*CLIENTFACTORY)(void);
+} cl_clientfunc_t;
+
+#endif /* _SDK_H */