diff --git a/.github/actions/numpy_vers/action.yml b/.github/actions/numpy_vers/action.yml
index d93dfff765..4df875b458 100644
--- a/.github/actions/numpy_vers/action.yml
+++ b/.github/actions/numpy_vers/action.yml
@@ -26,6 +26,14 @@ runs:
         case "${OS}:${ARCH}" in
             Linux:x86_64)
                 case "${{ inputs.pyver }}" in
+                    3.5*)
+                        NUMPY_BUILD_VERSION="==1.11.0"
+                        NUMPY_DEP_VERSION=">=1.11.0"
+                    ;;
+                    3.6*)
+                        NUMPY_BUILD_VERSION="==1.11.3"
+                        NUMPY_DEP_VERSION=">=1.11.3"
+                    ;;
                     3.7*)
                         NUMPY_BUILD_VERSION="==1.14.5"
                         NUMPY_DEP_VERSION=">=1.14.5"
@@ -35,8 +43,8 @@ runs:
                         NUMPY_DEP_VERSION=">=1.17.3"
                     ;;
                     3.9*)
-                        NUMPY_BUILD_VERSION="==1.19.4"
-                        NUMPY_DEP_VERSION=">=1.19.4"
+                        NUMPY_BUILD_VERSION="==1.19.3"
+                        NUMPY_DEP_VERSION=">=1.19.3"
                     ;;
                 esac
             ;;
@@ -49,15 +57,15 @@ runs:
                     ;;
                     3.7*)
                         NUMPY_BUILD_VERSION="==1.14.5"
-                        NUMPY_DEP_VERSION=">=1.14.5,<=1.17.0"
+                        NUMPY_DEP_VERSION=">=1.14.5"
                     ;;
                     3.8*)
                         NUMPY_BUILD_VERSION="==1.17.3"
-                        NUMPY_DEP_VERSION=">=1.17.3,<=1.17.3"
+                        NUMPY_DEP_VERSION=">=1.17.3"
                     ;;
                     3.9*)
-                        NUMPY_BUILD_VERSION="==1.19.4"
-                        NUMPY_DEP_VERSION=">=1.19.4"
+                        NUMPY_BUILD_VERSION="==1.19.3"
+                        NUMPY_DEP_VERSION=">=1.19.3"
                     ;;
                 esac
             ;;
@@ -66,23 +74,23 @@ runs:
                 case "${{ inputs.pyver }}" in
                     3.5*)
                         NUMPY_BUILD_VERSION="==1.11.0"
-                        NUMPY_DEP_VERSION=">=1.11.0,<1.12.0"
+                        NUMPY_DEP_VERSION=">=1.11.0"
                     ;;
                     3.6*)
                         NUMPY_BUILD_VERSION="==1.12.0"
-                        NUMPY_DEP_VERSION=">=1.12.0,<1.14.5"
+                        NUMPY_DEP_VERSION=">=1.12.0"
                     ;;
                     3.7*)
                         NUMPY_BUILD_VERSION="==1.14.5"
-                        NUMPY_DEP_VERSION=">=1.14.5,<=1.17.0"
+                        NUMPY_DEP_VERSION=">=1.14.5"
                     ;;
                     3.8*)
                         NUMPY_BUILD_VERSION="==1.17.3"
-                        NUMPY_DEP_VERSION=">=1.17.3,<=1.17.3"
+                        NUMPY_DEP_VERSION=">=1.17.3"
                     ;;
                     3.9*)
-                        NUMPY_BUILD_VERSION="==1.19.4"
-                        NUMPY_DEP_VERSION=">=1.19.4"
+                        NUMPY_BUILD_VERSION="==1.19.3"
+                        NUMPY_DEP_VERSION=">=1.19.3"
                     ;;
                 esac
             ;;
diff --git a/.github/workflows/build-and-test.yml b/.github/workflows/build-and-test.yml
index 5291d109bc..db548081cb 100644
--- a/.github/workflows/build-and-test.yml
+++ b/.github/workflows/build-and-test.yml
@@ -1,6 +1,6 @@
 name: "Builds and tests"
 on:
-  pull_request:
+  # pull_request:
   push:
     branches:
       - master
@@ -113,13 +113,16 @@ jobs:
     needs: [ swig_Linux ]
     runs-on: ubuntu-20.04
     if: ${{ github.event_name == 'pull_request' }}
+    strategy:
+      matrix:
+        python-version: [3.5, 3.6, 3.7, 3.8, 3.9]
     steps:
       - uses: actions/checkout@v2
         with:
           fetch-depth: 0
       - uses: actions/setup-python@v2
         with:
-          python-version: 3.6
+          python-version: ${{ matrix.python-version }}
       - run: |
           python --version
           pip --version
@@ -135,7 +138,7 @@ jobs:
       - id: get_numpy
         uses: ./.github/actions/numpy_vers
         with:
-          pyver: 3.6
+          pyver: ${{ matrix.python-version }}
       - name: Make decoder package
         run: |
           NUMPY_BUILD_VERSION=${{ steps.get_numpy.outputs.build_version }} \
@@ -651,13 +654,16 @@ jobs:
     needs: [ swig_macOS ]
     runs-on: macos-10.15
     if: ${{ github.event_name == 'pull_request' }}
+    strategy:
+      matrix:
+        python-version: [3.6.8, 3.7.9, 3.8.8, 3.9.2]
     steps:
       - uses: actions/checkout@v2
         with:
           fetch-depth: 0
       - uses: ./.github/actions/install-python-upstream
         with:
-          version: 3.6.8
+          version: ${{ matrix.python-version }}
       - run: |
           python --version
           pip --version
@@ -673,7 +679,7 @@ jobs:
       - id: get_numpy
         uses: ./.github/actions/numpy_vers
         with:
-          pyver: 3.6.8
+          pyver: ${{ matrix.python-version }}
       - name: Make decoder package
         run: |
           NUMPY_BUILD_VERSION=${{ steps.get_numpy.outputs.build_version }} \
@@ -1146,6 +1152,9 @@ jobs:
     name: "Win|Build CTC decoder Python package"
     needs: [swig_Windows_crosscompiled]
     runs-on: windows-2019
+    strategy:
+      matrix:
+        python-version: [3.6.8, 3.7.9, 3.8.8, 3.9.2]
     steps:
       - name: Switch git-bash shell to MSYS2 shell by adding MSYS2 path to PATH front
         run: echo "$MSYS2_SHELL_PATH" >> $GITHUB_PATH
@@ -1163,7 +1172,7 @@ jobs:
           fetch-depth: 0
       - uses: actions/setup-python@v2
         with:
-          python-version: 3.7.9
+          python-version: ${{ matrix.python-version }}
       - run: |
           python --version
           python -m pip --version
diff --git a/.github/workflows/build-windows-tf.yml b/.github/workflows/build-windows-tf.yml
new file mode 100644
index 0000000000..ff69260890
--- /dev/null
+++ b/.github/workflows/build-windows-tf.yml
@@ -0,0 +1,85 @@
+name: "Builds windows tf"
+on:
+  pull_request:
+  push:
+    branches:
+      - master
+env:
+  # Shared variables
+  CI_TASK_DIR: ${{ github.workspace }}
+  CI_ARTIFACTS_DIR: ${{ github.workspace }}/artifacts
+
+  # macOS specific
+  MACOSX_DEPLOYMENT_TARGET: "10.10"
+  CI_NODE_MODULES_NTH: 1
+
+  # Windows specific
+  CI_MSYS_VERSION: MSYS_NT-10.0-17763
+  MSYS2_SHELL_PATH: D:\a\_temp\msys\msys64\usr\bin
+defaults:
+  run:
+    shell: bash
+jobs:
+  tensorflow_opt-Windows:
+    name: "Win|Check TensorFlow cache"
+    runs-on: ubuntu-20.04
+    outputs:
+      status: ${{ steps.check_artifact_exists.outputs.status }}
+      cache_key: ${{ steps.get_cache_key.outputs.key }}
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 1
+      - id: get_cache_key
+        uses: ./.github/actions/get_cache_key
+        with:
+          extras: "7"
+      - id: check_artifact_exists
+        uses: ./.github/actions/check_artifact_exists
+        with:
+          name: ${{ steps.get_cache_key.outputs.key }}
+  build-tensorflow-Windows:
+    name: "Win|Build TensorFlow (opt)"
+    needs: tensorflow_opt-Windows
+    runs-on: windows-2019
+    steps:
+      - run: true
+        if: needs.tensorflow_opt-Windows.outputs.status == 'found'
+      - uses: mozilla/setup-msys2@v2
+        with:
+          msystem: MSYS
+          path-type: inherit
+          update: true
+          install: >-
+            git
+            patch
+            tar
+            unzip
+            zip
+        if: needs.tensorflow_opt-Windows.outputs.status == 'missing'
+      - uses: actions/setup-python@v2
+        with:
+          python-version: 3.7.9
+        if: needs.tensorflow_opt-Windows.outputs.status == 'missing'
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+          submodules: 'recursive'
+        if: needs.tensorflow_opt-Windows.outputs.status == 'missing'
+      # It's important that this PATH change only happens *after* the checkout
+      # above, because otherwise the checkout fails when persisisting the
+      # credentials for submodules due to using MSYS2 Git
+      - name: Switch git-bash shell to MSYS2 shell by adding MSYS2 path to PATH front
+        run: echo "$MSYS2_SHELL_PATH" >> $GITHUB_PATH
+        if: needs.tensorflow_opt-Windows.outputs.status == 'missing'
+      - run: ./ci_scripts/tf-setup.sh
+        if: needs.tensorflow_opt-Windows.outputs.status == 'missing'
+      - run: ./ci_scripts/tf-build.sh "--windows-cpu"
+        if: needs.tensorflow_opt-Windows.outputs.status == 'missing'
+      - run: ./ci_scripts/tf-package.sh
+        if: needs.tensorflow_opt-Windows.outputs.status == 'missing'
+      - uses: actions/upload-artifact@v2
+        with:
+          name: ${{ needs.tensorflow_opt-Windows.outputs.cache_key }}
+          path: ${{ github.workspace }}/artifacts/home.tar.xz
+        if: needs.tensorflow_opt-Windows.outputs.status == 'missing'
\ No newline at end of file
diff --git a/.github/workflows/docker.yml b/.github/workflows/docker.yml
index beeb95a1ba..5bfd2c386f 100644
--- a/.github/workflows/docker.yml
+++ b/.github/workflows/docker.yml
@@ -1,6 +1,6 @@
 name: "Docker Images"
 on:
-  pull_request:
+  # pull_request:
   push:
     branches:
       - master
diff --git a/README.rst b/README.rst
index 85520f02ea..40671524f5 100644
--- a/README.rst
+++ b/README.rst
@@ -29,3 +29,5 @@ For the latest release, including pre-trained models and checkpoints, `see the l
 For contribution guidelines, see `CONTRIBUTING.rst <CONTRIBUTING.rst>`_.
 
 For contact and support information, see `SUPPORT.rst <SUPPORT.rst>`_.
+
+checking
\ No newline at end of file
diff --git a/ci_scripts/tf-vars.sh b/ci_scripts/tf-vars.sh
index 6c024b36ca..26634cb1ac 100755
--- a/ci_scripts/tf-vars.sh
+++ b/ci_scripts/tf-vars.sh
@@ -37,7 +37,7 @@ elif [ "${OS}" = "${CI_MSYS_VERSION}" ]; then
     export CI_ARTIFACTS_DIR="$(cygpath ${CI_ARTIFACTS_DIR})"
 
     export DS_ROOT_TASK=${CI_TASK_DIR}
-    export BAZEL_VC="C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\VC"
+    export BAZEL_VC="C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools\VC"
     export BAZEL_VC_FULL_VERSION="14.28.29910"
     export MSYS2_ARG_CONV_EXCL='//'