diff --git a/.bazelrc b/.bazelrc
index 74a5037f617..3a70b4a46a5 100644
--- a/.bazelrc
+++ b/.bazelrc
@@ -148,6 +148,20 @@ build:windows --cxxopt='/std:c++20' --host_cxxopt='/std:c++20'
 build:windows --cxxopt='/await' --host_cxxopt='/await'
 build:windows --cxxopt='/wo4503' --host_cxxopt='/wo4503'
 build:windows --cxxopt='/DWINDOWS_LEAN_AND_MEAN' --host_cxxopt='/DWINDOWS_LEAN_AND_MEAN'
+build:windows --cxxopt='/D_CRT_USE_BUILTIN_OFFSETOF' --host_cxxopt='/D_CRT_USE_BUILTIN_OFFSETOF'
 # The `/std:c++14` argument is unused during boringssl compilation and we don't
 # want a warning when compiling each file.
 build:windows --cxxopt='-Wno-unused-command-line-argument' --host_cxxopt='-Wno-unused-command-line-argument'
+
+# The following are required on github runners temporarily due to
+# https://github.com/actions/runner-images/issues/8125
+# For reasons TBD, clang in LLVM 16 is including the MSFT version emmintrin.h in
+# preference to the very packaged in LLVM 16 when compiling these files. The compiler
+# command-line and environment set by Bazel is the same, modulo the LLVM version
+# strings.
+build:windows --per_file_copt='external/ssl/src/crypto/fipsmodule/bcm.\c@-imsvcC:\\Program Files\\LLVM\\lib\\clang\\16.0.6\\include' --host_per_file_copt='external/ssl/src/crypto/fipsmodule/bcm\.c@-imsvcC:\\Program Files\\LLVM\\lib\\clang\\16.0.6\\include'
+build:windows --per_file_copt='external/ssl/src/crypto/hrss/hrss\.c@-imsvcC:\\Program Files\\LLVM\\lib\\clang\\16.0.6\\include' --host_per_file_copt='external/ssl/src/crypto/hrss/hrss\.c@-imsvcC:\\Program Files\\LLVM\\lib\\clang\\16.0.6\\include'
+build:windows --per_file_copt='external/ssl/src/crypto/poly1305/poly1305_vec\.c@-imsvcC:\\Program Files\\LLVM\\lib\\clang\\16.0.6\\include' --host_per_file_copt='external/ssl/src/crypto/poly1305/poly1305_vec.c@-imsvcC:\\Program Files\\LLVM\\lib\\clang\\16.0.6\\include'
+build:windows --per_file_copt='external/v8/src/objects/literal-objects\.cc@-imsvcC:\\Program Files\\LLVM\\lib\\clang\\16.0.6\\include' --host_per_file_copt='external/v8/src/objects/literal-objects.cc@-imsvcC:\\Program Files\\LLVM\\lib\\clang\\16.0.6\\include'
+build:windows --per_file_copt='external/v8/src/runtime/runtime-object\.cc@-imsvcC:\\Program Files\\LLVM\\lib\\clang\\16.0.6\\include' --host_per_file_copt='external/v8/src/runtime/runtime-object.cc@-imsvcC:\\Program Files\\LLVM\\lib\\clang\\16.0.6\\include'
+build:windows --per_file_copt='external/v8/src/objects/swiss-name-dictionary\.cc@-imsvcC:\\Program Files\\LLVM\\lib\\clang\\16.0.6\\include' --host_per_file_copt='external/v8/src/objects/swiss-name-dictionary.cc@-imsvcC:\\Program Files\\LLVM\\lib\\clang\\16.0.6\\include'
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 18cba0e5550..2d0716a5d99 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -67,7 +67,11 @@ jobs:
         if: runner.os == 'Windows'
         run: |
           [System.IO.File]::WriteAllLines((Join-Path -Path $env:USERPROFILE -ChildPath '.bazelrc'), 'startup --output_user_root=C:/tmp')
-
+          # Upgrade to LLVM 16.0.6, default install is currently 15 (https://github.com/actions/runner-images/issues/8125).
+          # When we need to upgrade beyond LLVM 16.0.6, ${WORKSPACE}/.bazelrc will need updating.
+          choco upgrade llvm --version=16.0.6
+          # Work around bazel clang 16 include path bug (https://github.com/bazelbuild/bazel/issues/17863)
+          Move-Item -Path "C:\Program Files\LLVM\lib\clang\16" -Destination "C:\Program Files\LLVM\lib\clang\16.0.6"
       - name: Bazel build
         run: |
           bazelisk build --disk_cache=~/bazel-disk-cache  --remote_cache=https://bazel:${{ secrets.BAZEL_CACHE_KEY }}@bazel-remote-cache.devprod.cloudflare.dev -c opt //src/workerd/server:workerd
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 93940c5423f..8e7b2e1711a 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -12,14 +12,14 @@ jobs:
   test:
     strategy:
       matrix:
-        os: [ubuntu-20.04, macos-latest] # windows-2022 disabled due to actions/runner-images#812
+        os: [ubuntu-20.04, macos-latest, windows-2022]
         include:
           - os-name: linux
             os: ubuntu-20.04
           - os-name: macOS
             os: macos-latest
-          # - os-name: windows
-          #   os: windows-2022
+          - os-name: windows
+            os: windows-2022
       fail-fast: false
     runs-on: ${{ matrix.os }}
     name: test (${{ matrix.os-name }})
@@ -60,6 +60,11 @@ jobs:
         run: |
             [System.IO.File]::WriteAllLines((Join-Path -Path $env:USERPROFILE -ChildPath '.bazelrc'), 'startup --output_user_root=C:/tmp')
             [System.IO.File]::WriteAllLines((Join-Path -Path $env:USERPROFILE -ChildPath '.bazelrc'), 'build:windows --config=windows_no_dbg')
+            # Upgrade to LLVM 16.0.6, default install is currently 15 (https://github.com/actions/runner-images/issues/8125).
+            # When we need to upgrade beyond LLVM 16.0.6, ${WORKSPACE}/.bazelrc will need updating.
+            choco upgrade llvm --version=16.0.6
+            # Work around bazel clang 16 include path bug (https://github.com/bazelbuild/bazel/issues/17863)
+            Move-Item -Path "C:\Program Files\LLVM\lib\clang\16" -Destination "C:\Program Files\LLVM\lib\clang\16.0.6"
       - name: Bazel build
         # timestamps are no longer being added here, the GitHub logs include timestamps (Use
         # 'Show timestamps' on the web interface)