diff --git a/.github/workflows/validate.yml b/.github/workflows/validate.yml
index 05a98281..0eb2ebb5 100644
--- a/.github/workflows/validate.yml
+++ b/.github/workflows/validate.yml
@@ -228,7 +228,20 @@ env:
   # `index.toml` min_mcpp still does NOT move: the floor is about descriptor
   # GRAMMAR, and `mcpp xpkg parse` accepts pkgs/h/huxerui.huxerui.lua under
   # 2026.8.27.2, 2026.9.6.3, 2026.9.7.1 and 2026.9.11.2 alike.
-  MCPP_VERSION: "2026.9.12.3"
+  # ── 2026-09-15: raised 2026.9.12.3 -> 2026.9.15.2 ─────────────────────────
+  #
+  # `llvm.libcxx` 22.1.8.3 and `openkal-llvm-runtime` 0.9.7 state
+  # `[package] standard = "c++23"`, which from mcpp 2026.9.15.2 compiles a
+  # C++-layer provider's own sources at that level whatever the consumer's
+  # (mcpp-community/mcpp#641). Neither needs the newer engine to build here --
+  # an older engine reads a dependency's `standard` as it always did -- but the
+  # same release moves the object addresses of sources outside their declaring
+  # package, the host-tool scratch directory, and when a dependency's link form
+  # is decided, and this index is where those meet five hundred real
+  # manifests. One pin move, batched with the two descriptors.
+  #
+  # `index.toml` min_mcpp does not move: no descriptor grammar changed.
+  MCPP_VERSION: "2026.9.15.2"
 
 jobs:
   lint:
diff --git a/pkgs/l/llvm.libcxx.lua b/pkgs/l/llvm.libcxx.lua
index 92aa0a3c..01e4b5bb 100644
--- a/pkgs/l/llvm.libcxx.lua
+++ b/pkgs/l/llvm.libcxx.lua
@@ -31,6 +31,13 @@ package = {
 
     xpm = {
         linux = {
+            ["22.1.8.3"] = {
+                url    = {
+                    GLOBAL = "https://github.com/mcpplibs/libcxx/archive/refs/tags/22.1.8.3.tar.gz",
+                    CN     = "https://gitcode.com/mcpp-res/libcxx/releases/download/22.1.8.3/libcxx-22.1.8.3.tar.gz",
+                },
+                sha256 = "b73607978b37202c89f68bc3151c07d19d1925bb454adb2c10607b601f15071a",
+            },
             ["22.1.8.2"] = {
                 url    = {
                     GLOBAL = "https://github.com/mcpplibs/libcxx/archive/refs/tags/22.1.8.2.tar.gz",
@@ -47,6 +54,13 @@ package = {
             },
         },
         macosx = {
+            ["22.1.8.3"] = {
+                url    = {
+                    GLOBAL = "https://github.com/mcpplibs/libcxx/archive/refs/tags/22.1.8.3.tar.gz",
+                    CN     = "https://gitcode.com/mcpp-res/libcxx/releases/download/22.1.8.3/libcxx-22.1.8.3.tar.gz",
+                },
+                sha256 = "b73607978b37202c89f68bc3151c07d19d1925bb454adb2c10607b601f15071a",
+            },
             ["22.1.8.2"] = {
                 url    = {
                     GLOBAL = "https://github.com/mcpplibs/libcxx/archive/refs/tags/22.1.8.2.tar.gz",
@@ -63,6 +77,13 @@ package = {
             },
         },
         windows = {
+            ["22.1.8.3"] = {
+                url    = {
+                    GLOBAL = "https://github.com/mcpplibs/libcxx/archive/refs/tags/22.1.8.3.tar.gz",
+                    CN     = "https://gitcode.com/mcpp-res/libcxx/releases/download/22.1.8.3/libcxx-22.1.8.3.tar.gz",
+                },
+                sha256 = "b73607978b37202c89f68bc3151c07d19d1925bb454adb2c10607b601f15071a",
+            },
             ["22.1.8.2"] = {
                 url    = {
                     GLOBAL = "https://github.com/mcpplibs/libcxx/archive/refs/tags/22.1.8.2.tar.gz",
diff --git a/pkgs/o/openkal-llvm-runtime.lua b/pkgs/o/openkal-llvm-runtime.lua
index ce2607d2..e1727998 100644
--- a/pkgs/o/openkal-llvm-runtime.lua
+++ b/pkgs/o/openkal-llvm-runtime.lua
@@ -26,6 +26,13 @@ package = {
 
     xpm = {
         linux = {
+            ["0.9.7"] = {
+                url    = {
+                    GLOBAL = "https://github.com/mcpplibs/openkal-llvm-runtime/archive/refs/tags/0.9.7.tar.gz",
+                    CN     = "https://gitcode.com/mcpp-res/openkal-llvm-runtime/releases/download/0.9.7/openkal-llvm-runtime-0.9.7.tar.gz",
+                },
+                sha256 = "8914579fb3cbc0ad367c4e46fb986a63261202cadf25d34e8f01815ddeecdb78",
+            },
             ["0.9.6"] = {
                 url    = {
                     GLOBAL = "https://github.com/mcpplibs/openkal-llvm-runtime/archive/refs/tags/0.9.6.tar.gz",
@@ -161,6 +168,13 @@ package = {
             },
         },
         macosx = {
+            ["0.9.7"] = {
+                url    = {
+                    GLOBAL = "https://github.com/mcpplibs/openkal-llvm-runtime/archive/refs/tags/0.9.7.tar.gz",
+                    CN     = "https://gitcode.com/mcpp-res/openkal-llvm-runtime/releases/download/0.9.7/openkal-llvm-runtime-0.9.7.tar.gz",
+                },
+                sha256 = "8914579fb3cbc0ad367c4e46fb986a63261202cadf25d34e8f01815ddeecdb78",
+            },
             ["0.9.6"] = {
                 url    = {
                     GLOBAL = "https://github.com/mcpplibs/openkal-llvm-runtime/archive/refs/tags/0.9.6.tar.gz",
@@ -296,6 +310,13 @@ package = {
             },
         },
         windows = {
+            ["0.9.7"] = {
+                url    = {
+                    GLOBAL = "https://github.com/mcpplibs/openkal-llvm-runtime/archive/refs/tags/0.9.7.tar.gz",
+                    CN     = "https://gitcode.com/mcpp-res/openkal-llvm-runtime/releases/download/0.9.7/openkal-llvm-runtime-0.9.7.tar.gz",
+                },
+                sha256 = "8914579fb3cbc0ad367c4e46fb986a63261202cadf25d34e8f01815ddeecdb78",
+            },
             ["0.9.6"] = {
                 url    = {
                     GLOBAL = "https://github.com/mcpplibs/openkal-llvm-runtime/archive/refs/tags/0.9.6.tar.gz",