diff --git a/src/doompanning.cc b/src/doompanning.cc
index 0ce2ef6..43d7bc0 100644
--- a/src/doompanning.cc
+++ b/src/doompanning.cc
@@ -48,6 +48,7 @@ struct ControllerContext
 struct ControllerActions
 {
     int doomsToSpawn = 0;
+    bool quitAllDooms = false;
 };
 
 void spawn_doom(ControllerContext &ctx)
@@ -80,6 +81,24 @@ void spawn_doom(ControllerContext &ctx)
     log_info("Spawned doom#%zu, pid=%d", ds.id, ds.pid);
 }
 
+void quit_all_dooms(ControllerContext &ctx)
+{
+    // Publish { DP_MT_QuitDoom, doomid }.
+    {
+        nng_msg *msg = nullptr;
+        int res = 0;
+
+        if ((res = nng_msg_alloc(&msg, 0)))
+            dp_nng_fatal("ctrl/alloc", res);
+
+        if ((res = nng_msg_append_u16(msg, DP_MT_QuitDoom)))
+            dp_nng_fatal("ctrl/msg", res);
+
+        if ((res = nng_sendmsg(ctx.pub, msg, 0)))
+            dp_nng_fatal("ctrl/sendmsg", res);
+    }
+}
+
 void perform_actions(ControllerContext &ctx, const ControllerActions &actions)
 {
     if (actions.doomsToSpawn)
@@ -88,6 +107,12 @@ void perform_actions(ControllerContext &ctx, const ControllerActions &actions)
         for (int i=0; i<actions.doomsToSpawn; ++i)
             spawn_doom(ctx);
     }
+
+    if (actions.quitAllDooms)
+    {
+        log_info("Telling all dooms to quit");
+        quit_all_dooms(ctx);
+    }
 }
 
 void check_on_dooms(ControllerContext &ctx)
@@ -122,10 +147,10 @@ void do_networking(ControllerContext &ctx)
         nng_msg *msg = nullptr;
         int res = 0;
 
-        if ((res = nng_msg_alloc(&msg, sizeof(dmt_t))))
+        if ((res = nng_msg_alloc(&msg, 0)))
             dp_nng_fatal("ctrl/alloc", res);
 
-        if ((res = nng_msg_append_u16(msg, DP_MT_DoomReady)))
+        if ((res = nng_msg_append_u16(msg, DP_MT_RunDoom)))
             dp_nng_fatal("ctrl/msg", res);
 
         if ((res = nng_sendmsg(ctx.pub, msg, 0)))
@@ -209,11 +234,14 @@ ControllerActions run_ui(ControllerContext &ctx)
 
     ImGui::SliderInt("Layout columns##columns", &ctx.columns, 1, 32, "%d", ImGuiSliderFlags_AlwaysClamp);
 
-    ImGui::SliderInt("##dooms", &doomsToSpawn, 1, 16, "%d", ImGuiSliderFlags_AlwaysClamp);
+    ImGui::SliderInt("##dooms", &doomsToSpawn, 1, 256, "%d", ImGuiSliderFlags_AlwaysClamp | ImGuiSliderFlags_Logarithmic);
     aprintf(strbuf, "Spawn %d more doom%s###spawnmore", doomsToSpawn, doomsToSpawn > 1 ? "s" : "");
     if (ImGui::SameLine(); ImGui::Button(strbuf.data()))
         result.doomsToSpawn = doomsToSpawn;
 
+    if (ImGui::Button("Quit all Dooms"))
+        result.quitAllDooms = true;
+
     ImGui::PopItemWidth();
     ImGui::End();
 
diff --git a/src/doomsim.cc b/src/doomsim.cc
index c5695f9..9e8cec5 100644
--- a/src/doomsim.cc
+++ b/src/doomsim.cc
@@ -35,7 +35,7 @@ DEF_DOOM_STATE_FUNC(do_doom_ready)
     {
         nng_msg *msg = NULL;
 
-        if ((res = nng_msg_alloc(&msg, sizeof(dmt_t) + sizeof(doomid_t))))
+        if ((res = nng_msg_alloc(&msg, 0)))
             dp_nng_fatal("doom/alloc", res);
 
         if ((res = nng_msg_append_u16(msg, DP_MT_DoomReady)))
@@ -51,15 +51,12 @@ DEF_DOOM_STATE_FUNC(do_doom_ready)
     // Incoming Message |  Next State
     // -------------------------------
     // DP_MT_RunDoom    -> DP_DS_Running
-    // DP_MT_QuitDoom   -> DP_DS_Quit
+    // DP_MT_QuitDoom   -> DP_DS_Quitting
     // */none           -> DP_DS_Ready
     {
         nng_msg *msg = NULL;
 
-        if ((res = nng_msg_alloc(&msg, sizeof(int) + sizeof(doomid_t))))
-            dp_nng_fatal("doom/alloc", res);
-
-        if ((res = nng_recvmsg(ctx->sub, &msg, 0)))
+        if ((res = dp_recv_new_msg(ctx->sub, &msg)))
         {
             if (res != NNG_ETIMEDOUT)
                 dp_nng_fatal("doom/recvmsg", res);
@@ -67,6 +64,9 @@ DEF_DOOM_STATE_FUNC(do_doom_ready)
             return 0;
         }
 
+        auto len = nng_msg_len(msg);
+        log_trace("do_doom_ready received message of size %zu", len);
+
         dmt_t mt = DP_MT_Invalid;
 
         if ((res = nng_msg_trim_u16(msg, &mt)))
@@ -80,7 +80,12 @@ DEF_DOOM_STATE_FUNC(do_doom_ready)
             ctx->f = do_doom_running;
         }
         else if (mt == DP_MT_QuitDoom)
-            ctx->state = DP_DS_Quit;
+            // TODO: pop off the doomid and check against ours.
+            // TODO: add a QuitAllDooms message
+            ctx->state = DP_DS_Quitting;
+
+        // No error on receiving different message types because other dooms
+        // might get readied or be told to quit.
     }
 
     return res;
@@ -93,10 +98,35 @@ DEF_DOOM_STATE_FUNC(do_doom_running)
     // Non-blocking receive of incoming messages.
     // Check if we should quit.
     // Handle incoming input.
+    // Let doom render a new frame.
+    // Publish the frame.
 
-    // Let doom render a new frame
+    int res = 0;
+    nng_msg *msg = NULL;
 
-    // Publish the frame
+    // FIXME: this is blocking while testing things
+    if ((res = dp_recv_new_msg_nonblock(ctx->sub, &msg)))
+    {
+        if (res != NNG_ETIMEDOUT && res != NNG_EAGAIN)
+            dp_nng_fatal("doom/recvmsg", res);
+
+        return 0;
+    }
+
+    auto len = nng_msg_len(msg);
+    log_trace("do_doom_running received message of size %zu", len);
+
+    dmt_t mt = DP_MT_Invalid;
+
+    if ((res = nng_msg_trim_u16(msg, &mt)))
+        dp_nng_fatal("doom/msg_trim", res);
+
+    nng_msg_free(msg);
+
+    if (mt == DP_MT_QuitDoom)
+        ctx->state = DP_DS_Quitting;
+
+    // Otherwise stay in running state
 
     return 0;
 }
@@ -107,7 +137,7 @@ int doom_loop(DoomContext *ctx)
 
     int res = 0;
 
-    while (ctx->state != DP_DS_Quit && res == 0)
+    while (ctx->state != DP_DS_Quitting && res == 0)
     {
         DP_DoomState prevState = ctx->state;
         res = ctx->f(ctx);
@@ -123,6 +153,13 @@ int doom_loop(DoomContext *ctx)
 
 int main(int argc, char *argv[])
 {
+#ifndef NDEBUG
+    log_set_level(LOG_TRACE);
+#else
+    log_set_level(LOG_DEBUG);
+#endif
+    log_set_level(LOG_DEBUG); // FIXME: silence!
+
     log_info("doomsim starting");
 
     std::optional<doomid_t> doomId;
diff --git a/src/dp_common.c b/src/dp_common.c
index e882580..41451bb 100644
--- a/src/dp_common.c
+++ b/src/dp_common.c
@@ -1,5 +1,6 @@
 #include "dp_common.h"
 
+#include <assert.h>
 #include <errno.h>
 #include <nng/protocol/pubsub0/pub.h>
 #include <nng/protocol/pubsub0/sub.h>
@@ -49,7 +50,7 @@ nng_socket make_ctrl_sub(const char *url)
     if ((res = nng_sub0_open(&sock)))
         dp_nng_fatal("make_ctrl_sub/nng_sub0_open", res);
 
-    if ((res = nng_socket_set_string(sock, NNG_OPT_SUB_SUBSCRIBE, "")))
+    if ((res = nng_setopt(sock, NNG_OPT_SUB_SUBSCRIBE, "", 0)))
         dp_nng_fatal("make_ctrl_sub/subscribe", res);
 
     if ((res = nng_socket_set_ms(sock, NNG_OPT_RECVTIMEO, 100)))
@@ -84,7 +85,7 @@ nng_socket make_doom_sub(const char *url)
     if ((res = nng_sub0_open(&sock)))
         dp_nng_fatal("make_doom_sub/nng_sub0_open", res);
 
-    if ((res = nng_socket_set_string(sock, NNG_OPT_SUB_SUBSCRIBE, "")))
+    if ((res = nng_setopt(sock, NNG_OPT_SUB_SUBSCRIBE, "", 0)))
         dp_nng_fatal("make_doom_sub/subscribe", res);
 
     if ((res = nng_socket_set_ms(sock, NNG_OPT_RECVTIMEO, 100)))
@@ -96,12 +97,37 @@ nng_socket make_doom_sub(const char *url)
     return sock;
 }
 
-const char *const DP_DoomState_Strings[DP_DS_COUNT] =
+const char *const DP_DoomState_Strings[] =
 {
+    "DoomState_Unknown",
     "DoomState_Ready",
     "DoomState_Running",
     "DoomState_Quit",
 };
 
 _Static_assert(sizeof(DP_DoomState_Strings) / sizeof(DP_DoomState_Strings[0]) == DP_DS_COUNT,
-    "DP_DoomState enum and strings do not match up");
\ No newline at end of file
+    "DP_DoomState enum and strings do not match up");
+
+int dp_recv_new_msg(nng_socket sock, nng_msg **msg_ptr)
+{
+    return dp_recv_new_msg_flags(sock, msg_ptr, 0);
+}
+
+int dp_recv_new_msg_nonblock(nng_socket sock, nng_msg **msg_ptr)
+{
+    return dp_recv_new_msg_flags(sock, msg_ptr, NNG_FLAG_NONBLOCK);
+}
+
+int dp_recv_new_msg_flags(nng_socket sock, nng_msg **msg_ptr, int flags)
+{
+    assert(msg_ptr);
+    int res = 0;
+
+    if ((res = nng_recvmsg(sock, msg_ptr, flags)))
+    {
+        nng_msg_free(*msg_ptr);
+        *msg_ptr = NULL;
+    }
+
+    return res;
+}
\ No newline at end of file
diff --git a/src/dp_common.h b/src/dp_common.h
index 2535f0a..8670a28 100644
--- a/src/dp_common.h
+++ b/src/dp_common.h
@@ -42,7 +42,7 @@ typedef enum DP_DoomState
     DP_DS_Unknown,
     DP_DS_Ready,
     DP_DS_Running,
-    DP_DS_Quit,
+    DP_DS_Quitting,
     DP_DS_COUNT,
 } DP_DoomState;
 
@@ -53,6 +53,11 @@ static inline const char *doomstate_str(DP_DoomState ds)
     return DP_DoomState_Strings[ds];
 }
 
+int dp_recv_new_msg(nng_socket sock, nng_msg **msg_ptr);
+int dp_recv_new_msg_nonblock(nng_socket sock, nng_msg **msg_ptr);
+int dp_recv_new_msg_flags(nng_socket sock, nng_msg **msg_ptr, int flags);
+
+
 #ifdef __cplusplus
 }
 #endif