diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 790b3fd..a879edb 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -20,9 +20,11 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        clang-version: [ 20, 19, 18, 17, 16, 15, 14, 13, 12.0.1, 12, 11, 10, 9, 8]
+        clang-version: [ 21, 20, 19, 18, 17, 16, 15, 14, 13, 12.0.1, 12, 11, 10, 9]
         os: [ linux, macosx, windows ]
         include:
+          - clang-version: 21
+            release: llvm-project-21.1.0.src
           - clang-version: 20
             release: llvm-project-20.1.0.src
           - clang-version: 19
@@ -51,9 +53,6 @@ jobs:
           - clang-version: 9
             release: llvm-project-9.0.1
             extra-cmake-args: '-DLLVM_ENABLE_Z3_SOLVER=OFF'
-          - clang-version: 8
-            release: llvm-project-8.0.1
-            extra-cmake-args: '-DCLANG_ANALYZER_ENABLE_Z3_SOLVER=OFF'
           - os: linux
             runner: ubuntu-22.04
             os-cmake-args: '-DLLVM_BUILD_STATIC=ON -DCMAKE_CXX_FLAGS="-s -flto" ${POSIX_CMAKE_ARGS} ${LINUX_CMAKE_ARGS}'
@@ -91,42 +90,17 @@ jobs:
       # The commit hash of this repository into the clang binaries
       shell: bash
       run: curl -L https://github.com/${{ github.repository }}/archive/${{ github.ref }}.tar.gz | tar xvz --strip 1
-    - name: Get llvm-project
-      if: ${{ matrix.clang-version == 8 }}
-      shell: bash
-      run: |
-        version=${RELEASE##llvm-project-}
-        curl -LO https://github.com/llvm/llvm-project/releases/download/llvmorg-${version}/llvm-${version}.src.tar.xz
-        curl -LO https://github.com/llvm/llvm-project/releases/download/llvmorg-${version}/cfe-${version}.src.tar.xz
-        curl -LO https://github.com/llvm/llvm-project/releases/download/llvmorg-${version}/clang-tools-extra-${version}.src.tar.xz
     - name: Get llvm-project
       if: ${{ matrix.clang-version >= 9 || matrix.clang-version == '12.0.1' }}
       shell: bash
       run: |
         version=${RELEASE##llvm-project-}; version=${version%.src}
         curl -LO https://github.com/llvm/llvm-project/releases/download/llvmorg-${version}/${{ matrix.release }}.tar.xz
-
     - name: Unpack llvm-project
-      if: ${{ matrix.clang-version < 9 }}
       shell: bash
       run: |
-        version=${RELEASE##llvm-project-}
-        tar xf llvm-${version}.src.tar.xz
-        tar xf cfe-${version}.src.tar.xz ${{ matrix.extra-tar-args-cfe }}
-        tar xf clang-tools-extra-${version}.src.tar.xz
-        mkdir ${{ matrix.release }}
-        mv llvm-${version}.src ${{ matrix.release }}/llvm
-        mv cfe-${version}.src ${{ matrix.release }}/clang
-        mv clang-tools-extra-${version}.src ${{ matrix.release }}/clang-tools-extra
-    - name: Unpack llvm-project
-      if: ${{ matrix.clang-version >= 9 || matrix.clang-version == '12.0.1' }}
-      shell: bash
-      run: |
-        tar xf ${{ matrix.release }}.tar.xz ${{ matrix.extra-tar-args }}
-    - name: Patch clang-8 includes
-      if: ${{ matrix.clang-version == 8 }}
-      shell: bash
-      run: patch ${{ matrix.release }}/llvm/include/llvm/Demangle/MicrosoftDemangleNodes.h include-cstdint-string-prior-to-using-uint8_t.patch
+        # ignore failure on v21 on windows
+        tar xf ${{ matrix.release }}.tar.xz ${{ matrix.extra-tar-args }} || true
     - name: Patch trivially-copyable clang 9/10
       if: ${{ ( matrix.clang-version == 9 || matrix.clang-version == 10 ) && matrix.os == 'windows' }}
       shell: bash
diff --git a/README.md b/README.md
index 7db5a83..284d70d 100644
--- a/README.md
+++ b/README.md
@@ -9,7 +9,7 @@ Includes **[clang-format](https://clang.llvm.org/docs/ClangFormat.html), [clang-
 
 ## Clang Tools Version Support Matrix
 
-| Clang Tools |OS/Version |20|19|18 |17 |16 |15 |14 |13 |12 |11 |10 |9  |8  |
+| Clang Tools |OS/Version |21|20|19 |18 |17 |16 |15 |14 |13 |12 |11 |10 |9  |
 |:------------|-----------|--|--|---|---|---|---|---|---|---|---|---|---|---|
 |clang-format |Linux 64   |✔️|✔️|✔️ |✔️|✔️|✔️ |✔️|✔️ |✔️ |✔️|✔️| ✔️|✔️|
 |             |Window 64  |✔️|✔️|✔️ |✔️|✔️|✔️ |✔️|✔️ |✔️ |✔️|✔️| ✔️|✔️|
@@ -27,6 +27,8 @@ Includes **[clang-format](https://clang.llvm.org/docs/ClangFormat.html), [clang-
 > [!NOTE]
 >
 > Remove Support v7 (released in May 2019) by February 2025.
+>
+> Remove Support v8 (released in July 2019) by September 2025.
 
 ## Download
 
diff --git a/include-cstdint-string-prior-to-using-uint8_t.patch b/include-cstdint-string-prior-to-using-uint8_t.patch
deleted file mode 100644
index a49281b..0000000
--- a/include-cstdint-string-prior-to-using-uint8_t.patch
+++ /dev/null
@@ -1,37 +0,0 @@
-From b288d90b39f4b905c02092a9bfcfd6d78f99b191 Mon Sep 17 00:00:00 2001
-From: Than McIntosh <thanm@google.com>
-Date: Fri, 19 Jul 2019 13:13:54 +0000
-Subject: [PATCH] [NFC] include cstdint/string prior to using uint8_t/string
-
-Summary: include proper header prior to use of uint8_t typedef
-and std::string.
-
-Subscribers: llvm-commits
-
-Reviewers: cherry
-
-Tags: #llvm
-
-Differential Revision: https://reviews.llvm.org/D64937
-
-llvm-svn: 366572
----
- llvm/include/llvm/Demangle/MicrosoftDemangleNodes.h | 2 ++
- 1 file changed, 2 insertions(+)
-
-diff --git a/llvm/include/llvm/Demangle/MicrosoftDemangleNodes.h b/llvm/include/llvm/Demangle/MicrosoftDemangleNodes.h
-index da9d9d5bfdc0..3d47471f0ef0 100644
---- a/llvm/include/llvm/Demangle/MicrosoftDemangleNodes.h
-+++ b/llvm/include/llvm/Demangle/MicrosoftDemangleNodes.h
-@@ -16,6 +16,8 @@
- #include "llvm/Demangle/DemangleConfig.h"
- #include "llvm/Demangle/StringView.h"
- #include <array>
-+#include <cstdint>
-+#include <string>
- 
- namespace llvm {
- namespace itanium_demangle {
--- 
-2.31.1
-