diff --git a/.github/workflows/build-toolchain.yml b/.github/workflows/build-toolchain.yml
index 8eaf7bf02..3793b3648 100644
--- a/.github/workflows/build-toolchain.yml
+++ b/.github/workflows/build-toolchain.yml
@@ -156,6 +156,8 @@ jobs:
   context:
     runs-on: ubuntu-latest
     outputs:
+      brotli_revision: ${{ steps.context.outputs.brotli_revision }}
+      brotli_version: ${{ steps.context.outputs.brotli_version }}
       curl_revision: ${{ steps.context.outputs.curl_revision }}
       curl_version: ${{ steps.context.outputs.curl_version }}
       ds2_revision: ${{ steps.context.outputs.ds2_revision }}
@@ -281,6 +283,7 @@ jobs:
           ds2_revision=refs/tags/nightly-2024-11-07
           libxml2_revision=refs/tags/v2.11.5
           zlib_revision=refs/tags/v1.3.1
+          brotli_revision=refs/tags/v1.1.0
           EOF
           else
             repo manifest -r --suppress-upstream-revision --suppress-dest-branch | \
@@ -299,6 +302,7 @@ jobs:
           echo swift_toolchain_sqlite_version=3.46.0 >> ${GITHUB_OUTPUT}
           echo swift_cmark_version=0.29.0.gfm.13 >> ${GITHUB_OUTPUT}
           echo zlib_version=1.3 >> ${GITHUB_OUTPUT}
+          echo brotli_version=1.1.0 >> ${GITHUB_OUTPUT}
 
           # FIXME(z2oh): Remove /D_DISABLE_CONSTEXPR_MUTEX_CONSTRUCTOR when GitHub runner image updates to 20240610.1.
           #  see: https://github.com/actions/runner-images/issues/10004
@@ -569,6 +573,8 @@ jobs:
       curl_revision: ${{ needs.context.outputs.curl_revision }}
       curl_version: ${{ needs.context.outputs.curl_version }}
       ds2_revision: ${{ needs.context.outputs.ds2_revision }}
+      brotli_revision: ${{ needs.context.outputs.brotli_revision }}
+      brotli_version: ${{ needs.context.outputs.brotli_version }}
       indexstore_db_revision: ${{ needs.context.outputs.indexstore_db_revision }}
       libxml2_revision: ${{ needs.context.outputs.libxml2_revision }}
       libxml2_version: ${{ needs.context.outputs.libxml2_version }}
@@ -648,6 +654,8 @@ jobs:
       curl_revision: ${{ needs.context.outputs.curl_revision }}
       curl_version: ${{ needs.context.outputs.curl_version }}
       ds2_revision: ${{ needs.context.outputs.ds2_revision }}
+      brotli_revision: ${{ needs.context.outputs.brotli_revision }}
+      brotli_version: ${{ needs.context.outputs.brotli_version }}
       indexstore_db_revision: ${{ needs.context.outputs.indexstore_db_revision }}
       libxml2_revision: ${{ needs.context.outputs.libxml2_revision }}
       libxml2_version: ${{ needs.context.outputs.libxml2_version }}
diff --git a/.github/workflows/swift-toolchain.yml b/.github/workflows/swift-toolchain.yml
index deb29a4ef..feb0c72de 100644
--- a/.github/workflows/swift-toolchain.yml
+++ b/.github/workflows/swift-toolchain.yml
@@ -191,6 +191,14 @@ on:
         required: true
         type: string
 
+      brotli_revision:
+        required: true
+        type: string
+
+      brotli_version:
+        required: true
+        type: string
+
       ANDROID_API_LEVEL:
         required: true
         type: string
@@ -1311,6 +1319,94 @@ jobs:
           name: ${{ matrix.os }}-${{ matrix.arch }}-zlib-${{ inputs.zlib_version }}
           path: ${{ github.workspace }}/BuildRoot/Library/zlib-${{ inputs.zlib_version }}/usr
 
+  brotli:
+    runs-on: ${{ inputs.default_build_runner }}
+
+    strategy:
+      fail-fast: false
+      matrix: ${{ fromJSON(inputs.target_matrix) }}
+
+    name: ${{ matrix.os }} ${{ matrix.arch }} brotli
+
+    steps:
+      - uses: actions/checkout@v4.2.2
+        with:
+          path: ${{ github.workspace }}/SourceCache/ci-build
+          show-progress: false
+
+      - uses: ./SourceCache/ci-build/.github/actions/setup-build
+        with:
+          setup-vs-dev-env: ${{ matrix.os == 'Windows' }}
+          host-arch: ${{ matrix.arch }}
+      - uses: seanmiddleditch/gha-setup-ninja@96bed6edff20d1dd61ecff9b75cc519d516e6401 # master
+        if: inputs.build_os == 'Darwin'
+
+      - name: Compute workspace hash
+        id: workspace_hash
+        run: |
+          $stringAsStream = [System.IO.MemoryStream]::new()
+          $writer = [System.IO.StreamWriter]::new($stringAsStream)
+          $writer.write("${{ github.workspace }}")
+          $writer.Flush()
+          $stringAsStream.Position = 0
+          $hash = (Get-FileHash -Algorithm SHA256 -InputStream $stringAsStream).Hash
+          echo "hash=$hash" >> $env:GITHUB_OUTPUT
+      - name: Setup sccache
+        uses: ./SourceCache/ci-build/.github/actions/setup-sccache
+        with:
+          s3-bucket: ${{ vars.SCCACHE_S3_BUCKET }}
+          aws-region: ${{ vars.SCCACHE_AWS_REGION }}
+          aws-arn: ${{ vars.SCCACHE_AWS_ARN }}
+          disk-max-size: 100M
+          disk-cache-key: ${{ steps.workspace_hash.outputs.hash }}-${{ matrix.os }}-${{ matrix.arch }}-brotli
+
+      - uses: actions/checkout@v4.2.2
+        with:
+          repository: google/brotli
+          ref: ${{ inputs.brotli_revision }}
+          path: ${{ github.workspace }}/SourceCache/brotli
+          show-progress: false
+
+      - uses: nttld/setup-ndk@v1
+        if: matrix.os == 'Android'
+        id: setup-ndk
+        with:
+          ndk-version: ${{ inputs.ANDROID_NDK_VERSION }}
+          local-cache: true
+
+      - name: Configure brotli
+        uses: ./SourceCache/ci-build/.github/actions/configure-cmake-project
+        with:
+          project-name: brotli
+          swift-version: ${{ inputs.swift_version }}
+          enable-caching: true
+          debug-info: ${{ inputs.debug_info }}
+          build-os: ${{ inputs.build_os }}
+          build-arch: ${{ inputs.build_arch }}
+          os: ${{ matrix.os }}
+          arch: ${{ matrix.arch }}
+          src-dir: ${{ github.workspace }}/SourceCache/brotli
+          bin-dir: ${{ github.workspace }}/BinaryCache/brotli-${{ inputs.brotli_version }}
+          install-dir: ${{ github.workspace }}/BuildRoot/Library/brotli-${{ inputs.brotli_version }}/usr
+          android-api-level: ${{ inputs.ANDROID_API_LEVEL }}
+          android-clang-version: ${{ inputs.ANDROID_CLANG_VERSION }}
+          ndk-path: ${{ steps.setup-ndk.outputs.ndk-path }}
+          msvc-compilers: '@("C")'
+          cmake-defines: |
+            @{
+              'BUILD_SHARED_LIBS' = "NO";
+              'CMAKE_POSITION_INDEPENDENT_CODE' = "YES";
+            }
+      - name: Build brotli
+        run: cmake --build ${{ github.workspace }}/BinaryCache/brotli-${{ inputs.brotli_version }}
+      - name: Install brotli
+        run: cmake --build ${{ github.workspace }}/BinaryCache/brotli-${{ inputs.brotli_version }} --target install
+
+      - uses: actions/upload-artifact@v4
+        with:
+          name: ${{ matrix.os }}-${{ matrix.arch }}-brotli-${{ inputs.brotli_version }}
+          path: ${{ github.workspace }}/BuildRoot/Library/brotli-${{ inputs.brotli_version }}/usr
+
   curl:
     needs: [zlib]
     runs-on: ${{ inputs.default_build_runner }}