diff --git a/data/core/init.lua b/data/core/init.lua
index 2cf82344..500c1c26 100644
--- a/data/core/init.lua
+++ b/data/core/init.lua
@@ -154,7 +154,14 @@ end
 function core.project_subdir_set_show(dir, filename, show)
   dir.shown_subdir[filename] = show
   if dir.files_limit then
-    system.watch_dir_add(dir.watch_id, dir.name .. PATHSEP .. filename)
+    local fullpath = dir.name .. PATHSEP .. filename
+    if show then
+      local success = system.watch_dir_add(dir.watch_id, fullpath)
+      print("DEBUG: watch_dir_add", fullpath, "success:", success)
+    else
+      local success = system.watch_dir_rm(dir.watch_id, fullpath)
+      print("DEBUG: watch_dir_rm", fullpath, "success:", success)
+    end
   end
 end
 
diff --git a/resources/notes-dmon-integration-2.md b/resources/notes-dmon-integration-2.md
index 1ddb89c6..f0e0803c 100644
--- a/resources/notes-dmon-integration-2.md
+++ b/resources/notes-dmon-integration-2.md
@@ -1,10 +1,10 @@
 ## from core/init.lua
 
-- scan_project_folder set the watch_id recursively or not
-  * called from core.add_project_directory
+- `scan_project_folder` set the `watch_id` recursively or not
+  * called from `core.add_project_directory`
 
 ## from treeview.lua
 
-TreeView:on_mouse_pressed
-  * calls core.scan_project_subdir only in files_limit mode
-  * calls core.project_subdir_set_show
+`TreeView:on_mouse_pressed`
+  * calls `core.scan_project_subdir` only in `files_limit` mode
+  * calls `core.project_subdir_set_show`
diff --git a/src/api/system.c b/src/api/system.c
index 2d1e3dae..e904c923 100644
--- a/src/api/system.c
+++ b/src/api/system.c
@@ -660,8 +660,15 @@ static int f_watch_dir_add(lua_State *L) {
   dmon_watch_id watch_id;
   watch_id.id = luaL_checkinteger(L, 1);
   const char *subdir = luaL_checkstring(L, 2);
-  bool success = dmon_watch_add(watch_id, subdir);
-  lua_pushboolean(L, success);
+  lua_pushboolean(L, dmon_watch_add(watch_id, subdir));
+  return 1;
+}
+
+static int f_watch_dir_rm(lua_State *L) {
+  dmon_watch_id watch_id;
+  watch_id.id = luaL_checkinteger(L, 1);
+  const char *subdir = luaL_checkstring(L, 2);
+  lua_pushboolean(L, dmon_watch_rm(watch_id, subdir));
   return 1;
 }
 
@@ -751,6 +758,7 @@ static const luaL_Reg lib[] = {
   { "set_window_opacity",  f_set_window_opacity  },
   { "watch_dir",           f_watch_dir           },
   { "watch_dir_add",       f_watch_dir_add       },
+  { "watch_dir_rm",        f_watch_dir_rm        },
   { "path_compare",        f_path_compare        },
   { NULL, NULL }
 };
diff --git a/src/dmon.h b/src/dmon.h
index a1f6f38d..ad3dd730 100644
--- a/src/dmon.h
+++ b/src/dmon.h
@@ -116,6 +116,7 @@ DMON_API_DECL  dmon_watch_id dmon_watch(const char* rootdir,
                          uint32_t flags, void* user_data);
 DMON_API_DECL void dmon_unwatch(dmon_watch_id id);
 DMON_API_DECL bool dmon_watch_add(dmon_watch_id id, const char* subdir);
+DMON_API_DECL bool dmon_watch_rm(dmon_watch_id id, const char* subdir);
 
 #ifdef __cplusplus
 }
@@ -820,6 +821,38 @@ DMON_API_IMPL bool dmon_watch_add(dmon_watch_id id, const char* watchdir)
     return true;
 }
 
+DMON_API_IMPL bool dmon_watch_rm(dmon_watch_id id, const char* watchdir)
+{
+    DMON_ASSERT(id.id > 0 && id.id <= DMON_MAX_WATCHES);
+
+    pthread_mutex_lock(&_dmon.mutex);
+    dmon__watch_state* watch = &_dmon.watches[id.id - 1];
+
+    int i, c = stb_sb_count(watch->subdirs);
+    for (i = 0; i < c; i++) {
+        const dmon__watch_subdir *subdir = &watch->subdirs[i];
+        if (strcmp(subdir->rootdir, watchdir) == 0) {
+            break;
+        }
+    }
+    if (i >= c) {
+        _DMON_LOG_ERRORF("Watch directory '%s' is not valid", watchdir);
+        pthread_mutex_unlock(&_dmon.mutex);
+        return false;
+    }
+    inotify_rm_watch(fd, watch->wds[i]);
+
+    for (int j = i; j < c - 1; j++) {
+        memcpy(watch->subdir + j, watch->subdir + j + 1, sizeof(dmon__watch_subdir));
+        memcpy(watch->wds    + j, watch->wds    + j + 1, sizeof(int));
+    }
+    stb__sbraw(watch->subdir)[1] = c - 1;
+    stb__sbraw(watch->wds   )[1] = c - 1;
+
+    pthread_mutex_unlock(&_dmon.mutex);
+    return true;
+}
+
 _DMON_PRIVATE const char* dmon__find_subdir(const dmon__watch_state* watch, int wd)
 {
     const int* wds = watch->wds;