diff --git a/.github/workflows/linux-ci.yml b/.github/workflows/linux-ci.yml
index 3dd09a2..d610836 100644
--- a/.github/workflows/linux-ci.yml
+++ b/.github/workflows/linux-ci.yml
@@ -21,8 +21,8 @@ jobs:
       run: |
         sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test
         sudo apt-get update -qq
-        sudo apt-get install -y gcc-7 g++-7
-        sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-7 70 --slave /usr/bin/g++ g++ /usr/bin/g++-7
+        sudo apt-get install -y gcc-11 g++-11
+        sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 70 --slave /usr/bin/g++ g++ /usr/bin/g++-11
         sudo apt-get install -y tcl8.6-dev libcurl4-openssl-dev
     - name: configure	
       run: |       	
diff --git a/.github/workflows/mac-ci.yml b/.github/workflows/mac-ci.yml
index e3e69b7..07fad52 100644
--- a/.github/workflows/mac-ci.yml
+++ b/.github/workflows/mac-ci.yml
@@ -16,17 +16,11 @@ jobs:
     - name: Install dependencies
       run: |
         brew update
-        brew install tcl-tk || true
-        brew install curl
-        sudo mkdir -p /usr/local
-        sudo ln -sf /usr/local/opt/tcl-tk/include /usr/local/include/tcl8.6
-        sudo cp /usr/local/opt/tcl-tk/lib/libtcl* /usr/local/lib
-        sudo ln -sf /usr/local/opt/tcl-tk/bin/tclsh8.6 /usr/local/bin/tclsh
-        sudo ln -sf /usr/local/opt/tcl-tk/bin/tclsh8.6 /usr/local/bin/tclsh8.6
+        brew install tcl-tk autoconf curl
     - name: configure
       run: |       
         autoreconf -vi
-        ./configure --with-tcl=/usr/local/opt/tcl-tk/lib --prefix=/usr/local        
+        ./configure --with-tcl=/opt/homebrew/opt/tcl-tk/lib --prefix=/usr/local        
     - name: make
       run: make
     - name: install
diff --git a/.github/workflows/windows-ci.yml b/.github/workflows/windows-ci.yml
index 82c3162..917f82d 100644
--- a/.github/workflows/windows-ci.yml
+++ b/.github/workflows/windows-ci.yml
@@ -38,37 +38,13 @@ jobs:
     - name: Init MSVC
       uses: ilammy/msvc-dev-cmd@v1
 
-    - name: Cache vcpkg curl dependency
-      id: curl-cache
-      uses: actions/cache@v2
-      with:
-        path: C:/vcpkg/packages/curl_x64-windows-static
-        key: ${{ runner.os }}-vcpkgcurl
-
-    - name: Cache vcpkg zlib dependency
-      id: zlib-cache
-      uses: actions/cache@v2
-      with:
-        path: C:/vcpkg/packages/zlib_x64-windows-static
-        key: ${{ runner.os }}-vcpkgzlib
-
     - name: Install zlib with vcpkg
-      if: steps.zlib-cache.outputs.cache-hit != 'true'
       run: vcpkg install zlib:x64-windows-static
 
     - name: Install curl with vcpkg
-      if: steps.curl-cache.outputs.cache-hit != 'true'
       run: vcpkg install curl:x64-windows-static
 
-    - name: Cache Tcl build
-      id: tcl-cache
-      uses: actions/cache@v2
-      with:
-        path: C:/tcl
-        key: ${{ runner.os }}-vcpkgzlib
-
     - name: Build Tcl
-      if: steps.tcl-cache.outputs.cache-hit != 'true'
       working-directory: tcl/win
       shell: cmd
       run: |