diff --git a/config.inc.php b/config.inc.php
index aa6e788..4dfd4c4 100644
--- a/config.inc.php
+++ b/config.inc.php
@@ -29,12 +29,49 @@ task('config_worker', function(array $args)
   }
 });
 
-function config_base_dir()
+function config_base_dirs()
 {
-  if(is("CONFIGS_BASE_DIR"))
-    return get("CONFIGS_BASE_DIR");
-  else
-    return get("UNITY_ASSETS_DIR") . "/Configs";
+  static $dirs = null;
+
+  if($dirs === null)
+  {
+    if(is("CONFIGS_BASE_DIR"))
+    {
+      $dirs = get("CONFIGS_BASE_DIR");
+      if(is_string($dirs))
+        $dirs = array($dirs);
+    }
+    else
+      $dirs = array(get("UNITY_ASSETS_DIR") . "/Configs");
+
+    $dirs = array_map(function($d) { return normalize_path($d); }, $dirs);
+  }
+  return $dirs;
+}
+
+function config_map_base_dir($file, $normalized = false, $strict = true, $dirs = null)
+{
+  if(!is_array($dirs))
+    $dirs = config_base_dirs();
+  if(!$normalized)
+    $file = normalize_path($file);
+  foreach($dirs as $dir)
+    if(strpos($file, $dir) === 0)
+      return $dir;
+  if($strict)
+    throw new Exception("File '$file' is not mapped to any base dir");
+  return null;
+}
+
+function config_real_path($rel_path, $strict = true)
+{
+  $dirs = config_base_dirs();
+  foreach($dirs as $dir)
+    if(is_file($dir . '/' . $rel_path))
+      return $dir . '/' . $rel_path;
+  if($strict)
+    throw new Exception("No file for relative path '$rel_path'");
+  return null;
 }
 
 function config_build_dir()
@@ -79,7 +116,7 @@ function config_get_bundle_ext_path()
 
 function config_scan_files()
 {
-  return scan_files_rec(array(config_base_dir()), array('conf.js'));
+  return scan_files_rec(config_base_dirs(), array('conf.js'));
 }
 
 function config_pack_bundle(array $cache_entries, $use_lz4 = false, $use_config_refs = false)
@@ -231,16 +268,18 @@ function config_make_standalone_ext_bundle(array $configs, $file_path)
 
 function config_bench_load($file)
 {
-  list($proto_id, $_) = config_ensure_header(config_base_dir(), $file);
+  $base_dir = config_map_base_dir($file);
+
+  list($proto_id, $_) = config_ensure_header($base_dir, $file);
   if(!$proto_id)
     throw new Exception("Bad proto_id: {$proto_id}");
   $t = microtime(true);
-  $parse_res = config_parse(config_base_dir(), $file);
+  $parse_res = config_parse(config_base_dirs(), $file);
   if($parse_res->error !== 0)
     throw new Exception("Error({$parse_res->error}) while loading JSON from {$file}:\n" . $parse_res->error_descr);
   echo "PARSE: " . (microtime(true) - $t) . "\n";
   $t = microtime(true);
-  $config = config_load_ex(config_base_dir(), $file, $parse_res->parsed_arr, $proto_id); 
+  $config = config_load_ex($base_dir, $file, $parse_res->parsed_arr, $proto_id); 
   echo "LOAD: " . (microtime(true) - $t) . "\n";
 }
 
@@ -260,7 +299,7 @@ function config_load_includes_map($file = null)
 {
   $file = $file ? $file : config_get_includes_map_path();
 
-    $includes_map = array(array(), array());
+  $includes_map = array(array(), array());
 
   if(is_file($file))
   {
@@ -433,7 +472,10 @@ function _config_invalidate_cache($file, $cache_file) : ConfigCacheEntry
 {
   $cache_payload_file = config_get_cache_payload_path($file);
 
-  list($proto_id, $_) = config_ensure_header(config_base_dir(), $file);
+  //TODO: pass it from above?
+  $base_dir = config_map_base_dir($file);
+
+  list($proto_id, $_) = config_ensure_header($base_dir, $file);
   if(!$proto_id)
     throw new Exception("Bad proto_id: {$proto_id}");
 
@@ -441,13 +483,13 @@ function _config_invalidate_cache($file, $cache_file) : ConfigCacheEntry
   $GLOBALS['CONFIG_EXTRAS'] = ConfigCacheEntryExtras::create();
   $GLOBALS['CONFIG_BHL_FUNCS'] = array();
 
-  $pres = config_parse(config_base_dir(), $file);
+  $pres = config_parse(config_base_dirs(), $file);
   if($pres->error !== 0)
     throw new Exception("Error({$pres->error}) while loading JSON in {$file}:\n" . $pres->error_descr);
 
   $includes = config_get_module_includes($pres->jsm_module);
 
-  $config = config_load_ex(config_base_dir(), $file, $pres->parsed_arr, $proto_id); 
+  $config = config_load_ex($base_dir, $file, $pres->parsed_arr, $proto_id); 
   $payload_data = config_msgpack_pack($config->export());
 
   $cache_entry = new ConfigCacheEntry();
@@ -778,15 +820,14 @@ class ConfigParseResult
   public $jsm_module;
 }
 
-function config_parse($conf_dir, $file) : ConfigParseResult
+function config_parse(array $base_dirs, $file) : ConfigParseResult
 {
   $res = new ConfigParseResult();
 
-
   $normalized_jzon = '';
   try
   {
-    $jsm = new \JSM($conf_dir, $file);
+    $jsm = new \JSM($base_dirs, $file);
     list($normalized_jzon, $jsm_module) = $jsm->process();
     $res->normalized_jzon = $normalized_jzon;
     $res->jsm_module = $jsm_module;