diff --git a/cista/api.py b/cista/api.py
index 55c760c..c97d893 100644
--- a/cista/api.py
+++ b/cista/api.py
@@ -107,8 +107,8 @@ async def watch(req, ws):
         with watching.state.lock:
             q = watching.pubsub[uuid] = asyncio.Queue()
             # Init with disk usage and full tree
-            await ws.send(watching.format_du(watching.state.space))
-            await ws.send(watching.format_tree(watching.state.root))
+            await ws.send(watching.format_space(watching.state.space))
+            await ws.send(watching.format_root(watching.state.root))
         # Send updates
         while True:
             await ws.send(await q.get())
diff --git a/cista/watching.py b/cista/watching.py
index aa704e5..49c4f29 100644
--- a/cista/watching.py
+++ b/cista/watching.py
@@ -86,7 +86,6 @@ class State:
 
     def __getitem__(self, index: PurePosixPath | tuple[PurePosixPath, int]):
         with self.lock:
-            print(self._slice(index))
             return self._listing[self._slice(index)]
 
     def __setitem__(
@@ -153,8 +152,7 @@ def watcher_thread(loop):
         if old != new:
             with state.lock:
                 state.root = new
-                msg = format_tree(new)
-            asyncio.run_coroutine_threadsafe(broadcast(msg), loop).result()
+                broadcast(format_root(new), loop)
 
         # The watching is not entirely reliable, so do a full refresh every minute
         refreshdl = time.monotonic() + 60.0
@@ -167,9 +165,7 @@ def watcher_thread(loop):
             space = Space(*du, storage=state.root[0].size)
             if space != state.space:
                 state.space = space
-                asyncio.run_coroutine_threadsafe(
-                    broadcast(format_du(space)), loop
-                ).result()
+                broadcast(format_space(space), loop)
                 break
             # Do a full refresh?
             if time.monotonic() > refreshdl:
@@ -197,27 +193,20 @@ def watcher_thread_poll(loop):
         old = state.root
         new = walk()
         if old != new:
-            state.root = new
-            asyncio.run_coroutine_threadsafe(broadcast(format_tree(new)), loop).result()
+            with state.lock:
+                state.root = new
+                broadcast(format_update(old, new), loop)
 
         # Disk usage update
         du = shutil.disk_usage(rootpath)
         space = Space(*du, storage=state.root[0].size)
         if space != state.space:
             state.space = space
-            asyncio.run_coroutine_threadsafe(broadcast(format_du(space)), loop).result()
+            broadcast(format_space(space), loop)
 
         time.sleep(2.0)
 
 
-def format_du(usage):
-    return msgspec.json.encode({"space": usage}).decode()
-
-
-def format_tree(root):
-    return msgspec.json.encode({"root": root}).decode()
-
-
 def walk(rel=PurePosixPath()) -> list[FileEntry]:  # noqa: B008
     path = rootpath / rel
     try:
@@ -265,17 +254,16 @@ def update(relpath: PurePosixPath, loop):
     if rootpath is None or relpath is None:
         print("ERROR", rootpath, relpath)
     new = walk(relpath)
-    old = state[relpath]
-    if old == new:
-        return
-    old = state.root
-    if new:
-        state[relpath, new[0].isfile] = new
-    else:
-        del state[relpath]
-    # FIXME: broadcast format_update()
-    msg = format_update(old, state.root)
-    asyncio.run_coroutine_threadsafe(broadcast(msg), loop).result()
+    with state.lock:
+        old = state[relpath]
+        if old == new:
+            return
+        old = state.root
+        if new:
+            state[relpath, new[0].isfile] = new
+        else:
+            del state[relpath]
+        broadcast(format_update(old, state.root), loop)
 
 
 def format_update(old, new):
@@ -322,7 +310,19 @@ def format_update(old, new):
     return msgspec.json.encode({"update": update}).decode()
 
 
-async def broadcast(msg):
+def format_space(usage):
+    return msgspec.json.encode({"space": usage}).decode()
+
+
+def format_root(root):
+    return msgspec.json.encode({"root": root}).decode()
+
+
+def broadcast(msg, loop):
+    return asyncio.run_coroutine_threadsafe(abroadcast(msg), loop).result()
+
+
+async def abroadcast(msg):
     try:
         for queue in pubsub.values():
             queue.put_nowait(msg)