diff --git a/src/chsrc-main.c b/src/chsrc-main.c
index 896065e1..07f353e5 100644
--- a/src/chsrc-main.c
+++ b/src/chsrc-main.c
@@ -788,7 +788,6 @@ chefs_handle_Get_Source (Dish_t *dish, const char *input, char *option)
           Dish_t *sub_dish = xy_seq_at (dish->sub_dishes, i);
           sub_dish->preparefn();
           println (bdpurple(sub_dish->aliases));
-          chsrc_set_dish_group_mode();
           chefs_handle_Get_Source (sub_dish, dish_get_first_alias(sub_dish), option);
           br();
         }
@@ -814,6 +813,8 @@ chefs_handle_Set_Source (Dish_t *dish, const char *input, char *option)
 {
   if (dish_has_sub_dishes(dish))
     {
+      chsrc_begin_combo_source_resolution (dish);
+
       for (size_t i=0; i<xy_seq_len(dish->sub_dishes); i++)
         {
           Dish_t *sub_dish = xy_seq_at (dish->sub_dishes, i);
@@ -822,6 +823,8 @@ chefs_handle_Set_Source (Dish_t *dish, const char *input, char *option)
           chefs_handle_Set_Source (sub_dish, dish_get_first_alias(sub_dish), option);
           br();
         }
+
+      chsrc_end_combo_source_resolution ();
       return;
     }
 
diff --git a/src/framework/core.c b/src/framework/core.c
index 1a872cf9..60eda137 100644
--- a/src/framework/core.c
+++ b/src/framework/core.c
@@ -35,6 +35,9 @@
 
 static int chsrc_get_cpucore ();
 
+/* 定义于 dish.c，core.c 在 combo 源解析时需要提前声明 */
+bool dish_has_source_from_mirror (Dish_t *dish, const char *code);
+
 
 /* Global Program Mode */
 struct
@@ -43,9 +46,6 @@ struct
   bool MeasureMode;
   bool ResetMode;
 
-  // 内部实现
-  bool DishGroupMode;
-
   // 用户命令选项
   bool Ipv6Mode;
   Scope_t Scope;
@@ -57,7 +57,6 @@ ProgMode =
 {
   .MeasureMode = false,
   .ResetMode   = false,
-  .DishGroupMode = false,
   .Ipv6Mode = false,
   .Scope = ImplementationDefinedScope,
   .EnglishMode = false,
@@ -66,10 +65,9 @@ ProgMode =
 };
 
 /* recipe 相关 mode */
-bool chsrc_in_dish_group_mode() {return ProgMode.DishGroupMode;}
-// 并非作为 sub dish，而是自身作为一个独立的 dish 执行
-bool chsrc_in_standalone_mode() {return !ProgMode.DishGroupMode;}
-void chsrc_set_dish_group_mode(){ProgMode.DishGroupMode = true;}
+// combo dish 递归不再复用旧的 DishGroupMode；每个 leaf dish 仍负责自己的
+// 确认和收尾输出。
+bool chsrc_in_standalone_mode() {return true;}
 
 bool chsrc_in_reset_mode(){return ProgMode.ResetMode;}
 /* 默认换源作用域就是 ImplementationDefinedScope */
@@ -113,23 +111,29 @@ typedef enum ChgType_t
   ChgType_Untested
 } ChgType_t;
 
+#define MaxComboStackDepth 16
 
 /* Global Program Status */
 struct
 {
-  int leader_selected_index;   /* combo dish 选中的索引 */
-  ChgType_t chgtype;           /* 换源实现的类型 */
+  ChgType_t chgtype; /* 换源实现的类型 */
 
   /* 此时 chsrc_run() 不再是recipe中指定要运行的一个外部命令，而是作为一个功能实现的支撑 */
   bool chsrc_run_faas;
   char *user_agent;
+
+  /* combo dish 源解析上下文。用户只给一个 code/URL，但不同 sub dish 可能
+   * 使用不同的源列表；该栈记录当前正在处理的 combo dish。 */
+  Dish_t *ComboStack[MaxComboStackDepth];
+  XySeq_t *ComboBackedUpPaths[MaxComboStackDepth];
+  int ComboStackDepth;
 }
 ProgStatus =
 {
-  .leader_selected_index = -1,
   .chgtype = ChgType_Auto,
   .chsrc_run_faas = false,
   .user_agent = "chsrc/" Chsrc_Version,
+  .ComboStackDepth = 0,
 };
 
 
@@ -151,8 +155,6 @@ ProgStore =
   .contributors = NULL,
 };
 
-
-
 #define Exit_OK               0
 #define Exit_Fatal            1
 #define Exit_Unknown          2
@@ -175,6 +177,33 @@ ProgStore =
 /* 多语句必须括起来，否则在不带 { } 的 if else 等语句中会出错 */
 #define chsrc_breakdown(reason) { xy_error(App_Name "(BREAKDOWN)",reason); exit(Exit_MaintainerCause); }
 
+bool
+chsrc_in_dish_group_mode (void)
+{
+  return ProgStatus.ComboStackDepth > 0;
+}
+
+void
+chsrc_begin_combo_source_resolution (Dish_t *dish)
+{
+  if (ProgStatus.ComboStackDepth >= MaxComboStackDepth)
+    chsrc_breakdown ("combo dish 嵌套层级过深");
+
+  int depth = ProgStatus.ComboStackDepth;
+  ProgStatus.ComboStack[depth] = dish;
+  ProgStatus.ComboBackedUpPaths[depth] = xy_seq_new ();
+  ProgStatus.ComboStackDepth++;
+}
+
+void
+chsrc_end_combo_source_resolution (void)
+{
+  if (ProgStatus.ComboStackDepth <= 0)
+    chsrc_breakdown ("combo dish 解析上下文已为空");
+
+  ProgStatus.ComboStackDepth--;
+}
+
 #define faint(str)    xy_str2faint(str)
 #define red(str)      xy_str2red(str)
 #define blue(str)     xy_str2blue(str)
@@ -1039,6 +1068,54 @@ source_has_empty_url (Source_t *source)
   return source->url == NULL;
 }
 
+static bool
+subdish_sibling_has_source_from_mirror (Dish_t *current, const char *code)
+{
+  if (ProgStatus.ComboStackDepth <= 0)
+    return false;
+
+  Dish_t *combo = ProgStatus.ComboStack[ProgStatus.ComboStackDepth - 1];
+  if (!combo || !combo->sub_dishes)
+    return false;
+
+  for (size_t i=0; i < xy_seq_len(combo->sub_dishes); i++)
+    {
+      Dish_t *sub_dish = xy_seq_at (combo->sub_dishes, i);
+      if (sub_dish == current)
+        continue;
+
+      if (!sub_dish->inited)
+        sub_dish->preparefn ();
+
+      if (dish_has_source_from_mirror (sub_dish, code))
+        return true;
+    }
+
+  return false;
+}
+
+/**
+ * @brief 在 combo dish 中为当前 sub dish 解析源
+ *
+ * 用户只提供一个 code。若当前 sub dish 拥有该 code，直接使用它；否则，
+ * 若某个兄弟 sub dish 拥有该 code，说明该 code 仅属于另一类源，当前 sub
+ * dish 应自动测速选择其最快镜像。都不存在时走普通查询路径并报错。
+ */
+int
+chsrc_resolve_combo_subdish_source (Dish_t *dish, char *option)
+{
+  if (dish_has_source_from_mirror (dish, option))
+    return query_mirror_exist (dish->sources, dish->sources_n, dish->aliases, option);
+
+  if (subdish_sibling_has_source_from_mirror (dish, option))
+    return auto_select_mirror (dish->sources, dish->sources_n, dish->aliases);
+
+  chsrc_breakdown (ENGLISH
+                   ? "This combo sub dish has no source from the requested mirror"
+                   : "该 combo sub dish 没有所请求镜像站的源");
+  return 0;
+}
+
 
 
 /**
@@ -1051,10 +1128,9 @@ source_has_empty_url (Source_t *source)
  *   3. 用户什么都没指定，          即 chsrc set <dish>
  *   4. 用户正在重置源，            即 chsrc reset <dish>
  *
- * 如果处于 Dish Group 模式下，combo dish 已经测速过了，sub dish
- * 不能再次测速，而是直接选择 combo dish 测过的结果
- *
- *   5. combo dish 测速出来的某个源
+ * 如果处于 combo source resolution 上下文中，则按 sub dish 与 sibling
+ * 的源列表集中决定：code 命中本 dish 则直接使用；命中 sibling 则本 dish
+ * 自动测速；传入 URL 时，支持自定义 URL 的 sub dish 使用 URL，其余自动测速。
  *
  */
 Source_t
@@ -1069,14 +1145,29 @@ chsrc_yield_source (Dish_t *dish, char *option)
   if (!dish->inited) dish->preparefn();
 
   Source_t source;
-  if (chsrc_in_dish_group_mode() && ProgStatus.leader_selected_index==-1)
-    {
-      ProgStatus.leader_selected_index = use_specific_mirror_or_auto_select (option, dish);
-      source = dish->sources[ProgStatus.leader_selected_index];
-    }
-  else if (chsrc_in_dish_group_mode() && ProgStatus.leader_selected_index!=-1)
+  if (chsrc_in_dish_group_mode() && option)
     {
-      source = dish->sources[ProgStatus.leader_selected_index];
+      if (hp_is_url (option))
+        {
+          /* combo dish 传入 URL 时，支持该 sub dish 自定义 URL 的则直接使用；
+           * 不支持则自动选择该 sub dish 的最快源。这样 uv 可只把 URL 当作
+           * PyPI index，而 python-install-mirror 仍自动选择。 */
+          if (dish->can_user_define)
+            {
+              Source_t tmp = { &UserDefinedProvider, option };
+              source = tmp;
+            }
+          else
+            {
+              int index = auto_select_mirror (dish->sources, dish->sources_n, dish->aliases);
+              source = dish->sources[index];
+            }
+        }
+      else
+        {
+          int index = chsrc_resolve_combo_subdish_source (dish, option);
+          source = dish->sources[index];
+        }
     }
   else if (hp_is_url (option))
     {
@@ -1972,6 +2063,22 @@ chsrc_backup (const char *path)
       return;
     }
 
+  /* combo dish 中多个 sub dish 可能操作同一配置文件。首个 sub dish
+   * 已经保留原始内容后，后续 sub dish 不应再覆盖该备份。 */
+  if (chsrc_in_dish_group_mode())
+    {
+      int depth = ProgStatus.ComboStackDepth - 1;
+      XySeq_t *backed_up_paths = ProgStatus.ComboBackedUpPaths[depth];
+
+      for (size_t i=0; i < xy_seq_len(backed_up_paths); i++)
+        {
+          if (xy_streql (xy_seq_at (backed_up_paths, i), path))
+            goto log_anyway;
+        }
+
+      xy_seq_push (backed_up_paths, xy_strdup (path));
+    }
+
   if (xy.on_bsd || xy.on_macos)
     {
       /* BSD 和 macOS 的 cp 不支持 --backup 选项 */
diff --git a/src/framework/dish.c b/src/framework/dish.c
index 4b95c07e..a77f5192 100644
--- a/src/framework/dish.c
+++ b/src/framework/dish.c
@@ -35,3 +35,26 @@ dish_has_sub_dishes (Dish_t *dish)
 {
   return (dish->sub_dishes && xy_seq_len(dish->sub_dishes) > 1);
 }
+
+
+
+bool
+dish_has_source_from_mirror (Dish_t *dish, const char *code)
+{
+  if (!dish || !dish->sources || !code)
+    return false;
+
+  if (xy_streql (code, "upstream"))
+    return dish->sources_n > 0;
+
+  if (xy_streql (code, "first"))
+    return dish->sources_n > 1;
+
+  for (int i=0; i < dish->sources_n; i++)
+    {
+      if (xy_streql (dish->sources[i].mirror->code, code))
+        return true;
+    }
+
+  return false;
+}
diff --git a/src/recipe/lang/Python/uv/uv-python-build.c b/src/recipe/lang/Python/uv/uv-python-build.c
index 25624dca..11742fad 100644
--- a/src/recipe/lang/Python/uv/uv-python-build.c
+++ b/src/recipe/lang/Python/uv/uv-python-build.c
@@ -37,7 +37,10 @@ pl_uv_python_build_prepare (void)
   chef_set_default_scope (this, UserScope);
 
   chef_deny_english (this);
-  chef_allow_user_define (this);
+  chef_deny_user_define (this);
+  this->can_user_define_explain =
+    CHINESE ? "python-install-mirror 不支持手动指定，chsrc 会自动选择"
+            : "python-install-mirror cannot be specified manually; chsrc selects it automatically";
 
   def_sources_begin ()
   {&UpstreamProvider, "https://github.com/astral-sh/python-build-standalone/releases/download",       DelegateToUpstream},