diff --git a/data/core/init.lua b/data/core/init.lua
index fda0faff..2cf82344 100644
--- a/data/core/init.lua
+++ b/data/core/init.lua
@@ -153,6 +153,9 @@ 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)
+  end
 end
 
 
@@ -176,9 +179,13 @@ local function scan_project_folder(index)
   if entries_count > config.max_project_files then
     print("DEBUG setting files limit FLAG for", dir.name)
     dir.files_limit = true
+    -- Watch non-recursively
+    dir.watch_id = system.watch_dir(path, false)
     if core.status_view then -- May be not yet initialized.
       show_max_files_warning()
     end
+  else
+    dir.watch_id = system.watch_dir(path, true)
   end
   dir.files = t
   core.dir_rescan_add_job(dir, ".")
@@ -190,13 +197,13 @@ function core.add_project_directory(path)
   -- will be simply the name of the directory, without its path.
   -- The field item.topdir will identify it as a top level directory.
   path = normalize_path(path)
-  local watch_id = system.watch_dir(path);
+  -- local watch_id = system.watch_dir(path)
   local dir = {
     name = path,
     item = {filename = common.basename(path), type = "dir", topdir = true},
     files_limit = false,
     is_dirty = true,
-    watch_id = watch_id,
+    -- watch_id = watch_id,
     shown_subdir = {},
   }
   table.insert(core.project_directories, dir)
diff --git a/src/api/system.c b/src/api/system.c
index 0eb09108..2d1e3dae 100644
--- a/src/api/system.c
+++ b/src/api/system.c
@@ -648,12 +648,23 @@ static int f_set_window_opacity(lua_State *L) {
 
 static int f_watch_dir(lua_State *L) {
   const char *path = luaL_checkstring(L, 1);
-  dmon_watch_id watch_id = dmon_watch(path, dirmonitor_watch_callback, DMON_WATCHFLAGS_RECURSIVE, NULL);
+  const int recursive = lua_toboolean(L, 2);
+  uint32_t dmon_flags = (recursive ? DMON_WATCHFLAGS_RECURSIVE : 0);
+  dmon_watch_id watch_id = dmon_watch(path, dirmonitor_watch_callback, dmon_flags, NULL);
   if (watch_id.id == 0) { luaL_error(L, "directory monitoring watch failed"); }
   lua_pushnumber(L, watch_id.id);
   return 1;
 }
 
+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);
+  return 1;
+}
+
 #ifdef _WIN32
 #define PATHSEP '\\'
 #else
@@ -739,6 +750,7 @@ static const luaL_Reg lib[] = {
   { "fuzzy_match",         f_fuzzy_match         },
   { "set_window_opacity",  f_set_window_opacity  },
   { "watch_dir",           f_watch_dir           },
+  { "watch_dir_add",       f_watch_dir_add       },
   { "path_compare",        f_path_compare        },
   { NULL, NULL }
 };