diff --git a/.coveragerc b/.coveragerc
index ef820f0d4c6e..2e55f5c04844 100644
--- a/.coveragerc
+++ b/.coveragerc
@@ -1,15 +1,16 @@
 [run]
+parallel = True
 branch = True
+relative_files = True
 source =
-    cryptography
-    tests/
+    .
 
 [paths]
 source =
    src/cryptography
-   .tox/*/lib*/python*/site-packages/cryptography
-   .tox\*\Lib\site-packages\cryptography
-   .tox/pypy/site-packages/cryptography
+   *.tox/*/lib*/python*/site-packages/cryptography
+   *.tox\*\Lib\site-packages\cryptography
+   *.tox/pypy/site-packages/cryptography
 
 [report]
 exclude_lines =
diff --git a/.github/actions/upload-coverage/action.yml b/.github/actions/upload-coverage/action.yml
deleted file mode 100644
index 11d97a7a614d..000000000000
--- a/.github/actions/upload-coverage/action.yml
+++ /dev/null
@@ -1,19 +0,0 @@
-name: Upload Coverage
-description: Upload coverage to codecov
-
-inputs:
-  name:
-    description: "Job name"
-    required: true
-
-runs:
-  using: "composite"
-
-  steps:
-    - run: |
-        curl -o codecov.sh -f https://codecov.io/bash || \
-          curl -o codecov.sh -f https://codecov.io/bash || \
-          curl -o codecov.sh -f https://codecov.io/bash
-
-        bash codecov.sh -n "${{ inputs.name }}"
-      shell: bash
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a95d004ef671..fc488e42558e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -42,7 +42,7 @@ jobs:
           - {VERSION: "3.9", TOXENV: "py39", OPENSSL: {TYPE: "libressl", VERSION: "3.4.1"}}
           - {VERSION: "3.10", TOXENV: "py310"}
           # Latest commit on the main-with-bazel branch, as of November 8, 2021
-          - {VERSION: "3.10", TOXENV: "backend-import", OPENSSL: {TYPE: "boringssl", VERSION: "4fb158925f7753d80fb858cb0239dff893ef9f15"}}
+          - {VERSION: "3.10", TOXENV: "backend-import", OPENSSL: {TYPE: "boringssl", VERSION: "4fb158925f7753d80fb858cb0239dff893ef9f15"}, COVERAGE: "false"}
         RUST:
           - stable
     name: "${{ matrix.PYTHON.TOXENV }} ${{ matrix.PYTHON.OPENSSL.TYPE }} ${{ matrix.PYTHON.OPENSSL.VERSION }} ${{ matrix.PYTHON.TOXARGS }} ${{ matrix.PYTHON.OPENSSL.CONFIG_FLAGS }}"
@@ -76,7 +76,7 @@ jobs:
           repository: "google/wycheproof"
           path: "wycheproof"
           ref: "master"
-      - run: python -m pip install tox requests coverage
+      - run: python -m pip install tox requests git+https://github.com/alex/coveragepy@patch-1
       - name: Compute config hash and set config vars
         run: |
           DEFAULT_CONFIG_FLAGS="shared no-ssl2 no-ssl3"
@@ -116,8 +116,9 @@ jobs:
           TOXENV: ${{ matrix.PYTHON.TOXENV }}
           CARGO_TARGET_DIR: ${{ format('{0}/src/rust/target/', github.workspace) }}
 
-      - uses: ./.github/actions/upload-coverage
+      - uses: alex/github-actions-coverage-merge@main
         with:
+          mode: upload
           name: "tox -e ${{ matrix.PYTHON.TOXENV }} ${{ env.OSSL_INFO }}"
         if: matrix.PYTHON.COVERAGE != 'false'
 
@@ -165,13 +166,15 @@ jobs:
           echo "OPENSSL_FORCE_FIPS_MODE=1" >> $GITHUB_ENV
           echo "CFLAGS=-DUSE_OSRANDOM_RNG_FOR_TESTING" >> $GITHUB_ENV
         if: matrix.IMAGE.FIPS
+      - run: pip install git+https://github.com/alex/coveragepy@patch-1
       - run: 'tox -- --wycheproof-root="wycheproof"'
         env:
           TOXENV: ${{ matrix.IMAGE.TOXENV }}
           RUSTUP_HOME: /root/.rustup
           CARGO_TARGET_DIR: ${{ format('{0}/src/rust/target/', github.workspace) }}
-      - uses: ./.github/actions/upload-coverage
+      - uses: alex/github-actions-coverage-merge@main
         with:
+          mode: upload
           name: "${{ matrix.IMAGE.TOXENV }} on ${{ matrix.IMAGE.IMAGE }}"
 
   linux-rust:
@@ -217,15 +220,16 @@ jobs:
           repository: "google/wycheproof"
           path: "wycheproof"
           ref: "master"
-      - run: python -m pip install tox coverage
+      - run: python -m pip install tox git+https://github.com/alex/coveragepy@patch-1
       - name: Tests
         run: |
             tox -r --  --color=yes --wycheproof-root=wycheproof
         env:
           TOXENV: ${{ matrix.PYTHON.TOXENV }}
           CARGO_TARGET_DIR: ${{ format('{0}/src/rust/target/', github.workspace) }}
-      - uses: ./.github/actions/upload-coverage
+      - uses: alex/github-actions-coverage-merge@main
         with:
+          mode: upload
           name: "${{ matrix.PYTHON.TOXENV }} with Rust ${{ matrix.RUST }}"
 
   linux-rust-coverage:
@@ -275,7 +279,7 @@ jobs:
           repository: "google/wycheproof"
           path: "wycheproof"
           ref: "master"
-      - run: python -m pip install tox coverage
+      - run: python -m pip install tox git+https://github.com/alex/coveragepy@patch-1
       - name: Tests
         run: |
             tox -r --  --color=yes --wycheproof-root=wycheproof
@@ -313,8 +317,9 @@ jobs:
             sed -E -i 's/SF:src\/(.*)/SF:src\/rust\/src\/\1/g' ../../pytest-rust-cov.lcov
             sed -E -i 's/SF:src\/(.*)/SF:src\/rust\/src\/\1/g' ../../cargo-test-rust-cov.lcov
 
-      - uses: ./.github/actions/upload-coverage
+      - uses: alex/github-actions-coverage-merge@main
         with:
+          mode: upload
           name: "Rust Coverage"
 
   macos:
@@ -354,7 +359,7 @@ jobs:
           override: true
           default: true
 
-      - run: python -m pip install tox requests coverage
+      - run: python -m pip install tox requests git+https://github.com/alex/coveragepy@patch-1
 
       - uses: actions/checkout@v2.3.4
         with:
@@ -378,8 +383,9 @@ jobs:
           EXTRA_CFLAGS: ${{ matrix.PYTHON.EXTRA_CFLAGS }}
           CARGO_TARGET_DIR: ${{ format('{0}/src/rust/target/', github.workspace) }}
 
-      - uses: ./.github/actions/upload-coverage
+      - uses: alex/github-actions-coverage-merge@main
         with:
+          mode: upload
           name: "${{ matrix.PYTHON.TOXENV }} on macOS"
 
   windows:
@@ -426,7 +432,7 @@ jobs:
           default: true
           target: ${{ matrix.WINDOWS.RUST_TRIPLE }}
 
-      - run: python -m pip install tox requests coverage
+      - run: python -m pip install tox requests git+https://github.com/alex/coveragepy@patch-1
       - name: Download OpenSSL
         run: |
             python .github/workflows/download_openssl.py windows openssl-${{ matrix.WINDOWS.WINDOWS }}-${{ matrix.PYTHON.MSVC_VERSION }}
@@ -447,8 +453,9 @@ jobs:
           TOXENV: ${{ matrix.PYTHON.TOXENV }}
           CARGO_TARGET_DIR: ${{ format('{0}/src/rust/target/', github.workspace) }}
 
-      - uses: ./.github/actions/upload-coverage
+      - uses: alex/github-actions-coverage-merge@main
         with:
+          mode: upload
           name: "${{ matrix.PYTHON.TOXENV }} on ${{ matrix.WINDOWS.WINDOWS }} (part ${{ matrix.JOB_NUMBER }})"
 
   linux-downstream:
@@ -512,3 +519,14 @@ jobs:
     - run: echo "😢"; exit 1
       if: ${{ needs.linux.result != 'success' || needs.linux-distros.result != 'success' || needs.linux-rust.result != 'success' || needs.linux-rust-coverage.result != 'success' || needs.macos.result != 'success' || needs.windows.result != 'success' || needs.linux-downstream.result != 'success' }}
     - run: echo "🎉"
+
+  merge-coverage:
+    runs-on: ubuntu-latest
+    needs: [linux, linux-distros, linux-rust, linux-rust-coverage, macos, windows]
+    name: "Merge Coverage"
+    timeout-minutes: 10
+    steps:
+      - uses: actions/checkout@v2
+      - uses: alex/github-actions-coverage-merge@main
+        with:
+          mode: merge