diff --git a/demos/99-dung.c b/demos/99-dung.c
new file mode 100644
index 0000000..b07e7e8
--- /dev/null
+++ b/demos/99-dung.c
@@ -0,0 +1,176 @@
+#include "v4k.h"
+
+#define WS 32
+
+enum {
+    WALL=2, DOOR=4
+};
+
+typedef struct {
+    int16_t id:8;
+    int16_t flags:8;
+} cell_t;
+
+#define cell_t(...) C_CAST(cell_t, __VA_ARGS__)
+
+typedef struct {
+    cell_t grid[WS*WS];
+    mesh_t level;
+} world_t;
+
+static world_t world;
+
+void world_init() {
+    int i, j;
+    for (i = 0; i < WS; ++i) {
+        for (j = 0; j < WS; ++j) {
+            if (i == 0 || i == WS-1 || j == 0 || j == WS-1) {
+                // Border cells
+                world.grid[i*WS + j] = cell_t(0, WALL);
+            } else {
+                // Interior cells
+                world.grid[i*WS + j] = cell_t(rand()%3, 0);
+            }
+        }
+    }
+
+    world.level = mesh();
+
+
+    const int cube_vertices = 24;
+    const int cube_triangles = 12;
+    const int vertex_count = WS * WS * cube_vertices;
+    const int index_count = WS * WS * cube_triangles * 3;
+   
+    struct vert {
+        vec3 pos;
+        vec3 normal;
+    };
+
+    struct vert verts[vertex_count];
+
+    unsigned index_data[index_count];
+
+    int vertex_index = 0;
+    int index_index = 0;
+
+    static vec3 normals[6] = {
+        {1, 0, 0}, {-1, 0, 0},
+        {0, 1, 0}, {0, -1, 0},
+        {0, 0, 1}, {0, 0, -1}
+    };
+
+    for(int z = 0; z < WS; ++z) {
+        for(int x = 0; x < WS; ++x) {
+            if(world.grid[z*WS + x].id >= 0) {
+                for(int face = 0; face < 6; ++face) {
+                    for(int i = 0; i < 4; ++i) {
+                        
+                        vertex_index++;
+                    }
+                }
+                
+                // Create 12 triangles for the cube
+                static unsigned indices[12][3] = {
+                    {0, 1, 2}, {2, 1, 3}, {4, 5, 6}, {6, 5, 7},
+                    {0, 4, 1}, {1, 4, 5}, {2, 6, 3}, {3, 6, 7},
+                    {0, 2, 4}, {4, 2, 6}, {1, 3, 5}, {5, 3, 7}
+                };
+                for(int i = 0; i < 12; ++i) {
+                    for(int j = 0; j < 3; ++j) {
+                        index_data[index_index++] = vertex_index - 24 + indices[i][j];
+                    }
+                }
+            }
+        }
+    }
+
+    mesh_update(&world.level, "p3 n3", sizeof(struct vert), vertex_count, verts, index_count, index_data, 0);
+}
+
+void draw_world() {
+    static mat44 M;  do_once id44(M);
+    static mat44 VP; multiply44x2(VP, camera_get_active()->proj, camera_get_active()->view);
+
+    static const char *vs =
+    "#version 130\n"
+    "//" FILELINE "\n"
+    "uniform mat4 M,VP;\n"
+    "in vec3 att_position;\n"
+    "in vec3 att_normal;\n"
+    "out vec3 v_normal;\n"
+    "void main() {\n"
+    "   v_normal = normalize(att_position);\n"
+    "   gl_Position = M * VP * vec4( att_position, 1.0 );\n"
+    "}\n";
+    static const char *fs =
+    "#version 130\n"
+    "//" FILELINE "\n"
+    "in vec3 v_normal;\n"
+    "out vec4 fragcolor;\n"
+    "void main() {\n"
+        "fragcolor = vec4(v_normal, 1.0);\n" // diffuse
+    "}";
+
+    static unsigned program; do_once program = shader(vs, fs, "att_position,att_normal", "fragcolor");
+    shader_bind(program);
+    shader_mat44("VP", VP);
+    shader_mat44("M", M);
+
+    mesh_render(&world.level);
+}
+
+
+int main() {
+    window_create(80, WINDOW_MSAA8);
+    window_title(__FILE__);
+
+    // init world
+    world_init();
+
+    // load all fx files
+    fx_load("fx**.fs");
+
+    // load skybox
+    skybox_t sky = skybox(flag("--mie") ? 0 : "cubemaps/stardust", 0); // --mie for rayleigh/mie scattering
+
+    // camera
+    camera_t cam = camera();
+    cam.speed = 0.2f;
+
+    // audio (both clips & streams)
+    // audio_t SFX1 = audio_clip( "coin.wav" );
+    // audio_t SFX2 = audio_clip( "pew.sfxr" );
+    // audio_t BGM1 = audio_stream( "waterworld-map.fur"); // wrath_of_the_djinn.xm" );
+    // audio_t BGM2 = audio_stream( "larry.mid" );
+    // audio_t BGM3 = audio_stream( "monkey1.mid" ), BGM = BGM1;
+    // audio_play(SFX1, 0);
+    // audio_play(BGM1, 0);
+
+    while (window_swap()) {
+        // input
+        if( input_down(KEY_ESC) ) break;
+        if( input_down(KEY_F5) ) window_reload();
+        if( input_down(KEY_W) && input_held(KEY_LCTRL) ) break;
+        if( input_down(KEY_F11) ) window_fullscreen( window_has_fullscreen() ^ 1 );
+        if( input_down(KEY_X) ) window_screenshot(__FILE__ ".png");
+        if( input_down(KEY_Z) ) window_record(__FILE__ ".mp4");
+
+        // fps camera
+        bool active = ui_active() || ui_hover() || gizmo_active() ? false : input(MOUSE_L) || input(MOUSE_M) || input(MOUSE_R);
+        if( active ) cam.speed = clampf(cam.speed + input_diff(MOUSE_W) / 10, 0.05f, 5.0f);
+        vec2 mouse = scale2(vec2(input_diff(MOUSE_X), -input_diff(MOUSE_Y)), 0.2f * active);
+        vec3 wasdecq = scale3(vec3(input(KEY_D)-input(KEY_A),input(KEY_E)-(input(KEY_C)||input(KEY_Q)),input(KEY_W)-input(KEY_S)), cam.speed);
+        camera_move(&cam, wasdecq.x,wasdecq.y,wasdecq.z);
+        camera_fps(&cam, mouse.x,mouse.y);
+        window_cursor( !active );
+
+        fx_begin();
+            skybox_render(&sky, cam.proj, cam.view);
+
+            draw_world();
+        fx_end();
+    }
+
+    return 0;
+}
diff --git a/demos/99-syncdemo.c b/demos/99-syncdemo.c
index 57d8781..b48cf09 100644
--- a/demos/99-syncdemo.c
+++ b/demos/99-syncdemo.c
@@ -34,7 +34,7 @@ void bind_netbuffers(int64_t self_id) {
 
     for (int64_t i=0; i<MAX_CLIENTS; ++i) {
         world.player[i].color = colors[i%(sizeof colors / sizeof colors[0])];
-        network_buffer(&world.player[i], sizeof(struct player_t), i!=self_id ? NETWORK_RECV : NETWORK_SEND, i /* each client owns exactly 1 buffer */);
+        network_buffer(&world.player[i], sizeof(struct player_t), (i!=self_id ? NETWORK_RECV : NETWORK_SEND) | NETWORK_UNRELIABLE, i /* each client owns exactly 1 buffer */);
     };
 
     // register server->client rpc
@@ -56,6 +56,8 @@ int main() {
     window_create( 0.35f, WINDOW_MSAA8|WINDOW_SQUARE );
     struct player_t *self = &world.player[self_id];
 
+    network_put(NETWORK_SEND_MS, 33); // 0.033 s
+
     // game loop
     while( window_swap() && !input(KEY_ESC) ) {
         // network sync
diff --git a/engine/joint/v4k.h b/engine/joint/v4k.h
index 4997003..2a981f5 100644
--- a/engine/joint/v4k.h
+++ b/engine/joint/v4k.h
@@ -15921,17 +15921,18 @@ enum { MAX_CLIENTS = 32 };
 API void   network_create(const char *ip, const char *port, unsigned flags); // both ip and port can be null
 
 //enum { NETWORK_LOSSY, NETWORK_COMPRESS }; // post-processes
-//enum { NETWORK_UNRELIABLE, NETWORK_UNORDERED, NETWORK_PRIORITY }; // how
 //enum { NETWORK_PREDICT, NETWORK_RECONCILE, NETWORK_INTERPOLATE, NETWORK_COMPENSATE }; // time authority, when
 //enum { NETWORK_LAGS, NETWORK_DROPS, NETWORK_THROTTLES, NETWORK_DUPES }; // quality sim, how much
 //enum { NETWORK_CONST = 1, NETWORK_64,NETWORK_32,NETWORK_16,NETWORK_8, NETWORK_FLT, NETWORK_STR, NETWORK_BLOB }; // type, what
 enum { NETWORK_SEND = 2, NETWORK_RECV = 4 };
-API void*   network_buffer(void *ptr, unsigned sz, unsigned flags, int64_t rank); // configures a shared/networked buffer
+enum { NETWORK_UNRELIABLE = 8, NETWORK_UNORDERED = 16/*, NETWORK_PRIORITY = 32*/ };
+API void*   network_buffer(void *ptr, unsigned sz, uint64_t flags, int64_t rank); // configures a shared/networked buffer
 API char**  network_sync(unsigned timeout_ms); // syncs all buffers & returns null-terminated list of network events
 
 enum { NETWORK_RANK = 0 }; // [0..N] where 0 is server
 enum { NETWORK_PING = 1 }; // NETWORK_BANDWIDTH, NETWORK_QUALITY };
 enum { NETWORK_PORT = 2, NETWORK_IP, NETWORK_LIVE };
+enum { NETWORK_SEND_MS = 4 };
 //enum {  NETWORK_USERID, NETWORK_SALT, NETWORK_COUNT/*N users*/ /*...*/,
 API int64_t network_get(uint64_t key);
 API int64_t network_put(uint64_t key, int64_t value);
@@ -15945,7 +15946,9 @@ API void network_rpc_send(unsigned id, const char *cmdline);
 
 API bool server_bind(int max_clients, int port);
 API void server_poll();
+API void server_broadcast_bin_flags(const void *ptr, int len, uint64_t flags);
 API void server_broadcast_bin(const void *ptr, int len);
+API void server_broadcast_flags(const char *msg, uint64_t flags);
 API void server_broadcast(const char *msg);
 API void server_terminate();
 API void server_send(int64_t handle, const char *msg);
@@ -15953,7 +15956,9 @@ API void server_send_bin(int64_t handle, const void *ptr, int len);
 API void server_drop(int64_t handle);
 
 API int64_t  client_join(const char *ip, int port);
+#define      client_send_flags(msg,flags) server_broadcast(msg, flags)
 #define      client_send(msg) server_broadcast(msg)
+#define      client_send_bin_flags(ptr,len,flags) server_broadcast_bin(ptr, len, flags)
 #define      client_send_bin(ptr,len) server_broadcast_bin(ptr, len)
 #define      client_terminate() server_terminate()
 
@@ -338447,10 +338452,12 @@ typedef struct rpc_call {
     uint64_t function_hash;
 } rpc_call;
 
-#define RPC_SIGNATURE_i_iii UINT64_C(0x78409099752fa48a) // printf("%llx\n, HASH_STR("int(int,int,int)"));
-#define RPC_SIGNATURE_i_ii  UINT64_C(0x258290edf43985a5) // printf("%llx\n, HASH_STR("int(int,int)"));
-#define RPC_SIGNATURE_s_s   UINT64_C(0x97deedd17d9afb12) // printf("%llx\n, HASH_STR("char*(char*)"));
-#define RPC_SIGNATURE_s_v   UINT64_C(0x09c16a1242049b80) // printf("%llx\n, HASH_STR("char*(void)"));
+#define RPC_SIGNATURE_i_iii    UINT64_C(0x78409099752fa48a)
+#define RPC_SIGNATURE_i_ii     UINT64_C(0x258290edf43985a5)
+#define RPC_SIGNATURE_i_s      UINT64_C(0xf7b73162829ed667)
+#define RPC_SIGNATURE_s_s      UINT64_C(0x97deedd17d9afb12)
+#define RPC_SIGNATURE_s_v      UINT64_C(0x09c16a1242049b80)
+#define RPC_SIGNATURE_v_s      UINT64_C(0xc1746990ab73ed24)
 
 static
 rpc_call rpc_new_call(const char *signature, rpc_function function) {
@@ -338497,10 +338504,12 @@ char *rpc_full(unsigned id, const char* method, unsigned num_args, char *args[])
     rpc_call *found = map_find(rpc_calls, (char*)method);
     if( found ) {
         switch(found->function_hash) {
-            case RPC_SIGNATURE_i_iii: return va("%d %d", id, (int)(uintptr_t)found->function(atoi(args[0]), atoi(args[1]), atoi(args[2])) );
-            case RPC_SIGNATURE_i_ii:  return va("%d %d", id, (int)(uintptr_t)found->function(atoi(args[0]), atoi(args[1])) );
+            case RPC_SIGNATURE_i_iii: return va("%d %d", id, (int)(intptr_t)found->function(atoi(args[0]), atoi(args[1]), atoi(args[2])) );
+            case RPC_SIGNATURE_i_ii:  return va("%d %d", id, (int)(intptr_t)found->function(atoi(args[0]), atoi(args[1])) );
+            case RPC_SIGNATURE_i_s:   return va("%d %d", id, (int)(intptr_t)found->function(args[0]) );
             case RPC_SIGNATURE_s_s:   return va("%d %s", id, (char*)found->function(args[0]) );
             case RPC_SIGNATURE_s_v:   return va("%d %s", id, (char*)found->function() );
+            case RPC_SIGNATURE_v_s:   return va("%d", id), found->function(args[0]);
             default: break;
         }
     }
@@ -338718,11 +338727,19 @@ void client_poll() {
     }
 }
 
+void server_broadcast_bin_flags(const void *msg, int len, uint64_t flags) {
+    ENetPacket *packet = enet_packet_create(msg, len, flags&NETWORK_UNRELIABLE ? ENET_PACKET_FLAG_UNRELIABLE_FRAGMENT : ENET_PACKET_FLAG_RELIABLE | flags&(NETWORK_UNRELIABLE|NETWORK_UNORDERED) ? ENET_PACKET_FLAG_UNSEQUENCED : 0);
+    enet_host_broadcast(Server, 0, packet);
+}
+
 void server_broadcast_bin(const void *msg, int len) {
     ENetPacket *packet = enet_packet_create(msg, len, ENET_PACKET_FLAG_RELIABLE);
     enet_host_broadcast(Server, 0, packet);
     //enet_host_flush(Server); // flush if needed
 }
+void server_broadcast_flags(const char *msg, uint64_t flags) {
+    server_broadcast_bin_flags(msg, strlen(msg)+1, flags);
+}
 void server_broadcast(const char *msg) {
     server_broadcast_bin(msg, strlen(msg)+1);
 }
@@ -338820,12 +338837,15 @@ typedef struct netbuffer_t {
     int64_t owner;
     void *ptr;
     unsigned sz;
-    unsigned flags;
+    uint64_t flags;
 } netbuffer_t;
 
 static array(char*) events; // @todo: make event 128 bytes max?
 static array(int64_t) values; // @todo: map<key,values> instead?
 static map( int64_t, array(netbuffer_t) ) buffers; // map<client,array<netbuffer>>
+static double msg_send_cooldown = 0.0;
+static double network_dt = 0.0;
+static double last_netsync = 0.0;
 
 void network_create(const char *ip, const char *port_, unsigned flags) {
     if (buffers) map_clear(buffers);
@@ -338895,7 +338915,7 @@ int64_t network_get(uint64_t key) {
     return found ? *found : 0;
 }
 
-void* network_buffer(void *ptr, unsigned sz, unsigned flags, int64_t rank) {
+void* network_buffer(void *ptr, unsigned sz, uint64_t flags, int64_t rank) {
     assert(flags);
     array(netbuffer_t) *found = map_find_or_add(buffers, rank, NULL);
 
@@ -338916,26 +338936,33 @@ char** network_sync(unsigned timeout_ms) {
     bool is_server = whoami == 0;
     bool is_client = !is_server;
     if(timeout_ms < 2) timeout_ms = 2;
-    // sleep_ms(timeout_ms); // @fixme. server only?
+
+    network_dt = time_ss() - last_netsync;
+    last_netsync = time_ss();
 
     // Split buffers into clients @todo
     // clients need to do this before network polling; servers should do this after polling.
-    map_foreach(buffers, int64_t, rank, array(netbuffer_t), list) {
-        for(int i = 0, end = array_count(list); i < end; ++i) {
-            netbuffer_t *nb = &list[i];
-            if (!is_server && !(nb->flags & NETWORK_SEND))
-                continue;
-            static array(char) encapsulate;
-            array_resize(encapsulate, nb->sz + 28);
-            uint32_t *mid = (uint32_t*)&encapsulate[0]; *mid = MSG_BUF;
-            uint64_t *st = (uint64_t*)&encapsulate[4]; *st = nb->flags;
-            uint32_t *idx = (uint32_t*)&encapsulate[12]; *idx = i;
-            uint32_t *len = (uint32_t*)&encapsulate[16]; *len = nb->sz;
-            uint64_t *who = (uint64_t*)&encapsulate[20]; *who = nb->owner;
-            // PRINTF("sending %llx %u %lld %u\n", *st, *idx, *who, *len);
-            memcpy(&encapsulate[28], nb->ptr, nb->sz);
-            server_broadcast_bin(&encapsulate[0], nb->sz + 28);
+    if (msg_send_cooldown <= 0.0) {
+        map_foreach(buffers, int64_t, rank, array(netbuffer_t), list) {
+            for(int i = 0, end = array_count(list); i < end; ++i) {
+                netbuffer_t *nb = &list[i];
+                if (!is_server && !(nb->flags & NETWORK_SEND))
+                    continue;
+                static array(char) encapsulate;
+                array_resize(encapsulate, nb->sz + 28);
+                uint32_t *mid = (uint32_t*)&encapsulate[0]; *mid = MSG_BUF;
+                uint64_t *st = (uint64_t*)&encapsulate[4]; *st = nb->flags;
+                uint32_t *idx = (uint32_t*)&encapsulate[12]; *idx = i;
+                uint32_t *len = (uint32_t*)&encapsulate[16]; *len = nb->sz;
+                uint64_t *who = (uint64_t*)&encapsulate[20]; *who = nb->owner;
+                // PRINTF("sending %llx %u %lld %u\n", *st, *idx, *who, *len);
+                memcpy(&encapsulate[28], nb->ptr, nb->sz);
+                server_broadcast_bin(&encapsulate[0], nb->sz + 28);
+            }
         }
+        msg_send_cooldown = (double)network_get(NETWORK_SEND_MS)/1000.0;
+    } else {
+        msg_send_cooldown -= network_dt;
     }
 
     // network poll
diff --git a/engine/split/v4k_netsync.c b/engine/split/v4k_netsync.c
index fc40cd7..913ef28 100644
--- a/engine/split/v4k_netsync.c
+++ b/engine/split/v4k_netsync.c
@@ -6,10 +6,12 @@ typedef struct rpc_call {
     uint64_t function_hash;
 } rpc_call;
 
-#define RPC_SIGNATURE_i_iii UINT64_C(0x78409099752fa48a) // printf("%llx\n, HASH_STR("int(int,int,int)"));
-#define RPC_SIGNATURE_i_ii  UINT64_C(0x258290edf43985a5) // printf("%llx\n, HASH_STR("int(int,int)"));
-#define RPC_SIGNATURE_s_s   UINT64_C(0x97deedd17d9afb12) // printf("%llx\n, HASH_STR("char*(char*)"));
-#define RPC_SIGNATURE_s_v   UINT64_C(0x09c16a1242049b80) // printf("%llx\n, HASH_STR("char*(void)"));
+#define RPC_SIGNATURE_i_iii    UINT64_C(0x78409099752fa48a)
+#define RPC_SIGNATURE_i_ii     UINT64_C(0x258290edf43985a5)
+#define RPC_SIGNATURE_i_s      UINT64_C(0xf7b73162829ed667)
+#define RPC_SIGNATURE_s_s      UINT64_C(0x97deedd17d9afb12)
+#define RPC_SIGNATURE_s_v      UINT64_C(0x09c16a1242049b80)
+#define RPC_SIGNATURE_v_s      UINT64_C(0xc1746990ab73ed24)
 
 static
 rpc_call rpc_new_call(const char *signature, rpc_function function) {
@@ -56,10 +58,12 @@ char *rpc_full(unsigned id, const char* method, unsigned num_args, char *args[])
     rpc_call *found = map_find(rpc_calls, (char*)method);
     if( found ) {
         switch(found->function_hash) {
-            case RPC_SIGNATURE_i_iii: return va("%d %d", id, (int)(uintptr_t)found->function(atoi(args[0]), atoi(args[1]), atoi(args[2])) );
-            case RPC_SIGNATURE_i_ii:  return va("%d %d", id, (int)(uintptr_t)found->function(atoi(args[0]), atoi(args[1])) );
+            case RPC_SIGNATURE_i_iii: return va("%d %d", id, (int)(intptr_t)found->function(atoi(args[0]), atoi(args[1]), atoi(args[2])) );
+            case RPC_SIGNATURE_i_ii:  return va("%d %d", id, (int)(intptr_t)found->function(atoi(args[0]), atoi(args[1])) );
+            case RPC_SIGNATURE_i_s:   return va("%d %d", id, (int)(intptr_t)found->function(args[0]) );
             case RPC_SIGNATURE_s_s:   return va("%d %s", id, (char*)found->function(args[0]) );
             case RPC_SIGNATURE_s_v:   return va("%d %s", id, (char*)found->function() );
+            case RPC_SIGNATURE_v_s:   return va("%d", id), found->function(args[0]);
             default: break;
         }
     }
@@ -277,11 +281,19 @@ void client_poll() {
     }
 }
 
+void server_broadcast_bin_flags(const void *msg, int len, uint64_t flags) {
+    ENetPacket *packet = enet_packet_create(msg, len, flags&NETWORK_UNRELIABLE ? ENET_PACKET_FLAG_UNRELIABLE_FRAGMENT : ENET_PACKET_FLAG_RELIABLE | flags&(NETWORK_UNRELIABLE|NETWORK_UNORDERED) ? ENET_PACKET_FLAG_UNSEQUENCED : 0);
+    enet_host_broadcast(Server, 0, packet);
+}
+
 void server_broadcast_bin(const void *msg, int len) {
     ENetPacket *packet = enet_packet_create(msg, len, ENET_PACKET_FLAG_RELIABLE);
     enet_host_broadcast(Server, 0, packet);
     //enet_host_flush(Server); // flush if needed
 }
+void server_broadcast_flags(const char *msg, uint64_t flags) {
+    server_broadcast_bin_flags(msg, strlen(msg)+1, flags);
+}
 void server_broadcast(const char *msg) {
     server_broadcast_bin(msg, strlen(msg)+1);
 }
@@ -379,12 +391,15 @@ typedef struct netbuffer_t {
     int64_t owner;
     void *ptr;
     unsigned sz;
-    unsigned flags;
+    uint64_t flags;
 } netbuffer_t;
 
 static array(char*) events; // @todo: make event 128 bytes max?
 static array(int64_t) values; // @todo: map<key,values> instead?
 static map( int64_t, array(netbuffer_t) ) buffers; // map<client,array<netbuffer>>
+static double msg_send_cooldown = 0.0;
+static double network_dt = 0.0;
+static double last_netsync = 0.0;
 
 void network_create(const char *ip, const char *port_, unsigned flags) {
     if (buffers) map_clear(buffers);
@@ -454,7 +469,7 @@ int64_t network_get(uint64_t key) {
     return found ? *found : 0;
 }
 
-void* network_buffer(void *ptr, unsigned sz, unsigned flags, int64_t rank) {
+void* network_buffer(void *ptr, unsigned sz, uint64_t flags, int64_t rank) {
     assert(flags);
     array(netbuffer_t) *found = map_find_or_add(buffers, rank, NULL);
 
@@ -475,26 +490,33 @@ char** network_sync(unsigned timeout_ms) {
     bool is_server = whoami == 0;
     bool is_client = !is_server;
     if(timeout_ms < 2) timeout_ms = 2;
-    // sleep_ms(timeout_ms); // @fixme. server only?
+
+    network_dt = time_ss() - last_netsync;
+    last_netsync = time_ss();
 
     // Split buffers into clients @todo
     // clients need to do this before network polling; servers should do this after polling.
-    map_foreach(buffers, int64_t, rank, array(netbuffer_t), list) {
-        for(int i = 0, end = array_count(list); i < end; ++i) {
-            netbuffer_t *nb = &list[i];
-            if (!is_server && !(nb->flags & NETWORK_SEND))
-                continue;
-            static array(char) encapsulate;
-            array_resize(encapsulate, nb->sz + 28);
-            uint32_t *mid = (uint32_t*)&encapsulate[0]; *mid = MSG_BUF;
-            uint64_t *st = (uint64_t*)&encapsulate[4]; *st = nb->flags;
-            uint32_t *idx = (uint32_t*)&encapsulate[12]; *idx = i;
-            uint32_t *len = (uint32_t*)&encapsulate[16]; *len = nb->sz;
-            uint64_t *who = (uint64_t*)&encapsulate[20]; *who = nb->owner;
-            // PRINTF("sending %llx %u %lld %u\n", *st, *idx, *who, *len);
-            memcpy(&encapsulate[28], nb->ptr, nb->sz);
-            server_broadcast_bin(&encapsulate[0], nb->sz + 28);
+    if (msg_send_cooldown <= 0.0) {
+        map_foreach(buffers, int64_t, rank, array(netbuffer_t), list) {
+            for(int i = 0, end = array_count(list); i < end; ++i) {
+                netbuffer_t *nb = &list[i];
+                if (!is_server && !(nb->flags & NETWORK_SEND))
+                    continue;
+                static array(char) encapsulate;
+                array_resize(encapsulate, nb->sz + 28);
+                uint32_t *mid = (uint32_t*)&encapsulate[0]; *mid = MSG_BUF;
+                uint64_t *st = (uint64_t*)&encapsulate[4]; *st = nb->flags;
+                uint32_t *idx = (uint32_t*)&encapsulate[12]; *idx = i;
+                uint32_t *len = (uint32_t*)&encapsulate[16]; *len = nb->sz;
+                uint64_t *who = (uint64_t*)&encapsulate[20]; *who = nb->owner;
+                // PRINTF("sending %llx %u %lld %u\n", *st, *idx, *who, *len);
+                memcpy(&encapsulate[28], nb->ptr, nb->sz);
+                server_broadcast_bin(&encapsulate[0], nb->sz + 28);
+            }
         }
+        msg_send_cooldown = (double)network_get(NETWORK_SEND_MS)/1000.0;
+    } else {
+        msg_send_cooldown -= network_dt;
     }
 
     // network poll
diff --git a/engine/split/v4k_netsync.h b/engine/split/v4k_netsync.h
index 44d5e9c..95beb0f 100644
--- a/engine/split/v4k_netsync.h
+++ b/engine/split/v4k_netsync.h
@@ -18,17 +18,18 @@ enum { MAX_CLIENTS = 32 };
 API void   network_create(const char *ip, const char *port, unsigned flags); // both ip and port can be null
 
 //enum { NETWORK_LOSSY, NETWORK_COMPRESS }; // post-processes
-//enum { NETWORK_UNRELIABLE, NETWORK_UNORDERED, NETWORK_PRIORITY }; // how
 //enum { NETWORK_PREDICT, NETWORK_RECONCILE, NETWORK_INTERPOLATE, NETWORK_COMPENSATE }; // time authority, when
 //enum { NETWORK_LAGS, NETWORK_DROPS, NETWORK_THROTTLES, NETWORK_DUPES }; // quality sim, how much
 //enum { NETWORK_CONST = 1, NETWORK_64,NETWORK_32,NETWORK_16,NETWORK_8, NETWORK_FLT, NETWORK_STR, NETWORK_BLOB }; // type, what
 enum { NETWORK_SEND = 2, NETWORK_RECV = 4 };
-API void*   network_buffer(void *ptr, unsigned sz, unsigned flags, int64_t rank); // configures a shared/networked buffer
+enum { NETWORK_UNRELIABLE = 8, NETWORK_UNORDERED = 16/*, NETWORK_PRIORITY = 32*/ };
+API void*   network_buffer(void *ptr, unsigned sz, uint64_t flags, int64_t rank); // configures a shared/networked buffer
 API char**  network_sync(unsigned timeout_ms); // syncs all buffers & returns null-terminated list of network events
 
 enum { NETWORK_RANK = 0 }; // [0..N] where 0 is server
 enum { NETWORK_PING = 1 }; // NETWORK_BANDWIDTH, NETWORK_QUALITY };
 enum { NETWORK_PORT = 2, NETWORK_IP, NETWORK_LIVE };
+enum { NETWORK_SEND_MS = 4 };
 //enum {  NETWORK_USERID, NETWORK_SALT, NETWORK_COUNT/*N users*/ /*...*/,
 API int64_t network_get(uint64_t key);
 API int64_t network_put(uint64_t key, int64_t value);
@@ -42,7 +43,9 @@ API void network_rpc_send(unsigned id, const char *cmdline);
 
 API bool server_bind(int max_clients, int port);
 API void server_poll();
+API void server_broadcast_bin_flags(const void *ptr, int len, uint64_t flags);
 API void server_broadcast_bin(const void *ptr, int len);
+API void server_broadcast_flags(const char *msg, uint64_t flags);
 API void server_broadcast(const char *msg);
 API void server_terminate();
 API void server_send(int64_t handle, const char *msg);
@@ -50,7 +53,9 @@ API void server_send_bin(int64_t handle, const void *ptr, int len);
 API void server_drop(int64_t handle);
 
 API int64_t  client_join(const char *ip, int port);
+#define      client_send_flags(msg,flags) server_broadcast(msg, flags)
 #define      client_send(msg) server_broadcast(msg)
+#define      client_send_bin_flags(ptr,len,flags) server_broadcast_bin(ptr, len, flags)
 #define      client_send_bin(ptr,len) server_broadcast_bin(ptr, len)
 #define      client_terminate() server_terminate()
 
diff --git a/engine/v4k.c b/engine/v4k.c
index a88dab6..b9685dc 100644
--- a/engine/v4k.c
+++ b/engine/v4k.c
@@ -9483,10 +9483,12 @@ typedef struct rpc_call {
     uint64_t function_hash;
 } rpc_call;
 
-#define RPC_SIGNATURE_i_iii UINT64_C(0x78409099752fa48a) // printf("%llx\n, HASH_STR("int(int,int,int)"));
-#define RPC_SIGNATURE_i_ii  UINT64_C(0x258290edf43985a5) // printf("%llx\n, HASH_STR("int(int,int)"));
-#define RPC_SIGNATURE_s_s   UINT64_C(0x97deedd17d9afb12) // printf("%llx\n, HASH_STR("char*(char*)"));
-#define RPC_SIGNATURE_s_v   UINT64_C(0x09c16a1242049b80) // printf("%llx\n, HASH_STR("char*(void)"));
+#define RPC_SIGNATURE_i_iii    UINT64_C(0x78409099752fa48a)
+#define RPC_SIGNATURE_i_ii     UINT64_C(0x258290edf43985a5)
+#define RPC_SIGNATURE_i_s      UINT64_C(0xf7b73162829ed667)
+#define RPC_SIGNATURE_s_s      UINT64_C(0x97deedd17d9afb12)
+#define RPC_SIGNATURE_s_v      UINT64_C(0x09c16a1242049b80)
+#define RPC_SIGNATURE_v_s      UINT64_C(0xc1746990ab73ed24)
 
 static
 rpc_call rpc_new_call(const char *signature, rpc_function function) {
@@ -9533,10 +9535,12 @@ char *rpc_full(unsigned id, const char* method, unsigned num_args, char *args[])
     rpc_call *found = map_find(rpc_calls, (char*)method);
     if( found ) {
         switch(found->function_hash) {
-            case RPC_SIGNATURE_i_iii: return va("%d %d", id, (int)(uintptr_t)found->function(atoi(args[0]), atoi(args[1]), atoi(args[2])) );
-            case RPC_SIGNATURE_i_ii:  return va("%d %d", id, (int)(uintptr_t)found->function(atoi(args[0]), atoi(args[1])) );
+            case RPC_SIGNATURE_i_iii: return va("%d %d", id, (int)(intptr_t)found->function(atoi(args[0]), atoi(args[1]), atoi(args[2])) );
+            case RPC_SIGNATURE_i_ii:  return va("%d %d", id, (int)(intptr_t)found->function(atoi(args[0]), atoi(args[1])) );
+            case RPC_SIGNATURE_i_s:   return va("%d %d", id, (int)(intptr_t)found->function(args[0]) );
             case RPC_SIGNATURE_s_s:   return va("%d %s", id, (char*)found->function(args[0]) );
             case RPC_SIGNATURE_s_v:   return va("%d %s", id, (char*)found->function() );
+            case RPC_SIGNATURE_v_s:   return va("%d", id), found->function(args[0]);
             default: break;
         }
     }
@@ -9754,11 +9758,19 @@ void client_poll() {
     }
 }
 
+void server_broadcast_bin_flags(const void *msg, int len, uint64_t flags) {
+    ENetPacket *packet = enet_packet_create(msg, len, flags&NETWORK_UNRELIABLE ? ENET_PACKET_FLAG_UNRELIABLE_FRAGMENT : ENET_PACKET_FLAG_RELIABLE | flags&(NETWORK_UNRELIABLE|NETWORK_UNORDERED) ? ENET_PACKET_FLAG_UNSEQUENCED : 0);
+    enet_host_broadcast(Server, 0, packet);
+}
+
 void server_broadcast_bin(const void *msg, int len) {
     ENetPacket *packet = enet_packet_create(msg, len, ENET_PACKET_FLAG_RELIABLE);
     enet_host_broadcast(Server, 0, packet);
     //enet_host_flush(Server); // flush if needed
 }
+void server_broadcast_flags(const char *msg, uint64_t flags) {
+    server_broadcast_bin_flags(msg, strlen(msg)+1, flags);
+}
 void server_broadcast(const char *msg) {
     server_broadcast_bin(msg, strlen(msg)+1);
 }
@@ -9856,12 +9868,15 @@ typedef struct netbuffer_t {
     int64_t owner;
     void *ptr;
     unsigned sz;
-    unsigned flags;
+    uint64_t flags;
 } netbuffer_t;
 
 static array(char*) events; // @todo: make event 128 bytes max?
 static array(int64_t) values; // @todo: map<key,values> instead?
 static map( int64_t, array(netbuffer_t) ) buffers; // map<client,array<netbuffer>>
+static double msg_send_cooldown = 0.0;
+static double network_dt = 0.0;
+static double last_netsync = 0.0;
 
 void network_create(const char *ip, const char *port_, unsigned flags) {
     if (buffers) map_clear(buffers);
@@ -9931,7 +9946,7 @@ int64_t network_get(uint64_t key) {
     return found ? *found : 0;
 }
 
-void* network_buffer(void *ptr, unsigned sz, unsigned flags, int64_t rank) {
+void* network_buffer(void *ptr, unsigned sz, uint64_t flags, int64_t rank) {
     assert(flags);
     array(netbuffer_t) *found = map_find_or_add(buffers, rank, NULL);
 
@@ -9952,26 +9967,33 @@ char** network_sync(unsigned timeout_ms) {
     bool is_server = whoami == 0;
     bool is_client = !is_server;
     if(timeout_ms < 2) timeout_ms = 2;
-    // sleep_ms(timeout_ms); // @fixme. server only?
+
+    network_dt = time_ss() - last_netsync;
+    last_netsync = time_ss();
 
     // Split buffers into clients @todo
     // clients need to do this before network polling; servers should do this after polling.
-    map_foreach(buffers, int64_t, rank, array(netbuffer_t), list) {
-        for(int i = 0, end = array_count(list); i < end; ++i) {
-            netbuffer_t *nb = &list[i];
-            if (!is_server && !(nb->flags & NETWORK_SEND))
-                continue;
-            static array(char) encapsulate;
-            array_resize(encapsulate, nb->sz + 28);
-            uint32_t *mid = (uint32_t*)&encapsulate[0]; *mid = MSG_BUF;
-            uint64_t *st = (uint64_t*)&encapsulate[4]; *st = nb->flags;
-            uint32_t *idx = (uint32_t*)&encapsulate[12]; *idx = i;
-            uint32_t *len = (uint32_t*)&encapsulate[16]; *len = nb->sz;
-            uint64_t *who = (uint64_t*)&encapsulate[20]; *who = nb->owner;
-            // PRINTF("sending %llx %u %lld %u\n", *st, *idx, *who, *len);
-            memcpy(&encapsulate[28], nb->ptr, nb->sz);
-            server_broadcast_bin(&encapsulate[0], nb->sz + 28);
+    if (msg_send_cooldown <= 0.0) {
+        map_foreach(buffers, int64_t, rank, array(netbuffer_t), list) {
+            for(int i = 0, end = array_count(list); i < end; ++i) {
+                netbuffer_t *nb = &list[i];
+                if (!is_server && !(nb->flags & NETWORK_SEND))
+                    continue;
+                static array(char) encapsulate;
+                array_resize(encapsulate, nb->sz + 28);
+                uint32_t *mid = (uint32_t*)&encapsulate[0]; *mid = MSG_BUF;
+                uint64_t *st = (uint64_t*)&encapsulate[4]; *st = nb->flags;
+                uint32_t *idx = (uint32_t*)&encapsulate[12]; *idx = i;
+                uint32_t *len = (uint32_t*)&encapsulate[16]; *len = nb->sz;
+                uint64_t *who = (uint64_t*)&encapsulate[20]; *who = nb->owner;
+                // PRINTF("sending %llx %u %lld %u\n", *st, *idx, *who, *len);
+                memcpy(&encapsulate[28], nb->ptr, nb->sz);
+                server_broadcast_bin(&encapsulate[0], nb->sz + 28);
+            }
         }
+        msg_send_cooldown = (double)network_get(NETWORK_SEND_MS)/1000.0;
+    } else {
+        msg_send_cooldown -= network_dt;
     }
 
     // network poll
diff --git a/engine/v4k.h b/engine/v4k.h
index 51615d2..c63443b 100644
--- a/engine/v4k.h
+++ b/engine/v4k.h
@@ -2004,17 +2004,18 @@ enum { MAX_CLIENTS = 32 };
 API void   network_create(const char *ip, const char *port, unsigned flags); // both ip and port can be null
 
 //enum { NETWORK_LOSSY, NETWORK_COMPRESS }; // post-processes
-//enum { NETWORK_UNRELIABLE, NETWORK_UNORDERED, NETWORK_PRIORITY }; // how
 //enum { NETWORK_PREDICT, NETWORK_RECONCILE, NETWORK_INTERPOLATE, NETWORK_COMPENSATE }; // time authority, when
 //enum { NETWORK_LAGS, NETWORK_DROPS, NETWORK_THROTTLES, NETWORK_DUPES }; // quality sim, how much
 //enum { NETWORK_CONST = 1, NETWORK_64,NETWORK_32,NETWORK_16,NETWORK_8, NETWORK_FLT, NETWORK_STR, NETWORK_BLOB }; // type, what
 enum { NETWORK_SEND = 2, NETWORK_RECV = 4 };
-API void*   network_buffer(void *ptr, unsigned sz, unsigned flags, int64_t rank); // configures a shared/networked buffer
+enum { NETWORK_UNRELIABLE = 8, NETWORK_UNORDERED = 16/*, NETWORK_PRIORITY = 32*/ };
+API void*   network_buffer(void *ptr, unsigned sz, uint64_t flags, int64_t rank); // configures a shared/networked buffer
 API char**  network_sync(unsigned timeout_ms); // syncs all buffers & returns null-terminated list of network events
 
 enum { NETWORK_RANK = 0 }; // [0..N] where 0 is server
 enum { NETWORK_PING = 1 }; // NETWORK_BANDWIDTH, NETWORK_QUALITY };
 enum { NETWORK_PORT = 2, NETWORK_IP, NETWORK_LIVE };
+enum { NETWORK_SEND_MS = 4 };
 //enum {  NETWORK_USERID, NETWORK_SALT, NETWORK_COUNT/*N users*/ /*...*/,
 API int64_t network_get(uint64_t key);
 API int64_t network_put(uint64_t key, int64_t value);
@@ -2028,7 +2029,9 @@ API void network_rpc_send(unsigned id, const char *cmdline);
 
 API bool server_bind(int max_clients, int port);
 API void server_poll();
+API void server_broadcast_bin_flags(const void *ptr, int len, uint64_t flags);
 API void server_broadcast_bin(const void *ptr, int len);
+API void server_broadcast_flags(const char *msg, uint64_t flags);
 API void server_broadcast(const char *msg);
 API void server_terminate();
 API void server_send(int64_t handle, const char *msg);
@@ -2036,7 +2039,9 @@ API void server_send_bin(int64_t handle, const void *ptr, int len);
 API void server_drop(int64_t handle);
 
 API int64_t  client_join(const char *ip, int port);
+#define      client_send_flags(msg,flags) server_broadcast(msg, flags)
 #define      client_send(msg) server_broadcast(msg)
+#define      client_send_bin_flags(ptr,len,flags) server_broadcast_bin(ptr, len, flags)
 #define      client_send_bin(ptr,len) server_broadcast_bin(ptr, len)
 #define      client_terminate() server_terminate()