diff --git a/.github/workflows/ci_examples_java.yml b/.github/workflows/ci_examples_java.yml
index d33c4fc93..2442416e7 100644
--- a/.github/workflows/ci_examples_java.yml
+++ b/.github/workflows/ci_examples_java.yml
@@ -29,7 +29,11 @@ jobs:
       max-parallel: 1
       matrix:
         java-version: [8, 11, 16, 17]
-        os: [macos-13]
+        os: [
+            ubuntu-22.04,
+            # TODO: Re-enable macOS after https://t.corp.amazon.com/P205755286
+            # macos-13,
+          ]
     runs-on: ${{ matrix.os }}
     permissions:
       id-token: write
diff --git a/.github/workflows/ci_examples_net.yml b/.github/workflows/ci_examples_net.yml
index 4e50a975b..71d79307f 100644
--- a/.github/workflows/ci_examples_net.yml
+++ b/.github/workflows/ci_examples_net.yml
@@ -27,7 +27,11 @@ jobs:
       matrix:
         library: [DynamoDbEncryption]
         dotnet-version: ["6.0.x"]
-        os: [macos-13]
+        os: [
+            ubuntu-22.04,
+            # TODO: Re-enable macOS after https://t.corp.amazon.com/P205755286
+            # macos-13,
+          ]
     runs-on: ${{ matrix.os }}
     permissions:
       id-token: write
diff --git a/.github/workflows/ci_test_java.yml b/.github/workflows/ci_test_java.yml
index 66e0bfe17..f4f2b3d0e 100644
--- a/.github/workflows/ci_test_java.yml
+++ b/.github/workflows/ci_test_java.yml
@@ -29,7 +29,11 @@ jobs:
       matrix:
         library: [DynamoDbEncryption]
         java-version: [8, 11, 16, 17]
-        os: [macos-13]
+        os: [
+            ubuntu-22.04,
+            # TODO: Re-enable macOS after https://t.corp.amazon.com/P205755286
+            # macos-13,
+          ]
     runs-on: ${{ matrix.os }}
     permissions:
       id-token: write
diff --git a/.github/workflows/ci_test_net.yml b/.github/workflows/ci_test_net.yml
index f8e6f7dec..51b22498a 100644
--- a/.github/workflows/ci_test_net.yml
+++ b/.github/workflows/ci_test_net.yml
@@ -25,7 +25,12 @@ jobs:
       matrix:
         library: [DynamoDbEncryption]
         dotnet-version: ["6.0.x"]
-        os: [macos-13, ubuntu-22.04, windows-latest]
+        os: [
+            # TODO: Re-enable macOS after https://t.corp.amazon.com/P205755286
+            # macos-13,
+            ubuntu-latest,
+            windows-latest,
+          ]
     runs-on: ${{ matrix.os }}
     permissions:
       id-token: write
diff --git a/.github/workflows/dafny_interop_examples_java.yml b/.github/workflows/dafny_interop_examples_java.yml
index 09cbddf1d..cd9ff576c 100644
--- a/.github/workflows/dafny_interop_examples_java.yml
+++ b/.github/workflows/dafny_interop_examples_java.yml
@@ -28,7 +28,11 @@ jobs:
       max-parallel: 1
       matrix:
         java-version: [8, 11, 16, 17]
-        os: [macos-13]
+        os: [
+            # TODO: Re-enable macOS after https://t.corp.amazon.com/P205755286
+            # macos-13,
+            ubuntu-latest,
+          ]
     runs-on: ${{ matrix.os }}
     permissions:
       id-token: write
diff --git a/.github/workflows/dafny_interop_examples_net.yml b/.github/workflows/dafny_interop_examples_net.yml
index 7698ec173..9970b7303 100644
--- a/.github/workflows/dafny_interop_examples_net.yml
+++ b/.github/workflows/dafny_interop_examples_net.yml
@@ -24,7 +24,11 @@ jobs:
       matrix:
         library: [DynamoDbEncryption]
         dotnet-version: ["6.0.x"]
-        os: [macos-13]
+        os: [
+            # TODO: Re-enable macOS after https://t.corp.amazon.com/P205755286
+            # macos-13,
+            ubuntu-latest,
+          ]
     runs-on: ${{ matrix.os }}
     permissions:
       id-token: write
diff --git a/.github/workflows/dafny_interop_java.yml b/.github/workflows/dafny_interop_java.yml
index b5147c8c4..59b1221c5 100644
--- a/.github/workflows/dafny_interop_java.yml
+++ b/.github/workflows/dafny_interop_java.yml
@@ -28,7 +28,11 @@ jobs:
       matrix:
         library: [DynamoDbEncryption]
         java-version: [8, 11, 16, 17]
-        os: [macos-13]
+        os: [
+            # TODO: Re-enable macOS after https://t.corp.amazon.com/P205755286
+            # macos-13,
+            ubuntu-latest,
+          ]
     runs-on: ${{ matrix.os }}
     permissions:
       id-token: write
diff --git a/.github/workflows/library_dafny_verification.yml b/.github/workflows/library_dafny_verification.yml
index 21f25c39f..559af2cae 100644
--- a/.github/workflows/library_dafny_verification.yml
+++ b/.github/workflows/library_dafny_verification.yml
@@ -39,7 +39,11 @@ jobs:
             DynamoDbItemEncryptor,
             StructuredEncryption,
           ]
-        os: [macos-13]
+        os: [
+            # TODO: Re-enable macOS after https://t.corp.amazon.com/P205755286
+            # macos-13,
+            ubuntu-latest,
+          ]
     runs-on: ${{ matrix.os }}
     defaults:
       run:
diff --git a/.github/workflows/library_format.yml b/.github/workflows/library_format.yml
index fa37e073a..f270eea59 100644
--- a/.github/workflows/library_format.yml
+++ b/.github/workflows/library_format.yml
@@ -19,7 +19,11 @@ jobs:
     if: github.event_name != 'schedule' || github.repository_owner == 'aws'
     strategy:
       matrix:
-        os: [macos-13]
+        os: [
+            # TODO: Re-enable macOS after https://t.corp.amazon.com/P205755286
+            # macos-13,
+            ubuntu-latest,
+          ]
     runs-on: ${{ matrix.os }}
     defaults:
       run:
diff --git a/.github/workflows/library_rust_tests.yml b/.github/workflows/library_rust_tests.yml
index 3d75df2a2..0e79635e8 100644
--- a/.github/workflows/library_rust_tests.yml
+++ b/.github/workflows/library_rust_tests.yml
@@ -26,7 +26,16 @@ jobs:
       matrix:
         library: [DynamoDbEncryption, TestVectors]
         # removed windows-latest because somehow it can't build aws-lc in CI
-        os: [ubuntu-22.04, macos-13]
+        os: [
+            # TODO fix Dafny-generated tests on Windows;
+            # the sys.path workaround for generated Dafny doesn't work on Windows.
+            # Note: only tests use the sys.path workaround, not source code.
+            # Windows source code is tested downstream (ex. ESDK-Python CI).
+            # windows-latest,
+            ubuntu-22.04,
+            # TODO: Re-enable macOS after https://t.corp.amazon.com/P205755286
+            # macos-13,
+          ]
     runs-on: ${{ matrix.os }}
     permissions:
       id-token: write
diff --git a/.github/workflows/test_vector_verification.yml b/.github/workflows/test_vector_verification.yml
index 6d0fad611..421a1106d 100644
--- a/.github/workflows/test_vector_verification.yml
+++ b/.github/workflows/test_vector_verification.yml
@@ -29,7 +29,11 @@ jobs:
     if: github.event_name != 'schedule' || github.repository_owner == 'aws'
     strategy:
       matrix:
-        os: [macos-13]
+        os: [
+            # TODO: Re-enable macOS after https://t.corp.amazon.com/P205755286
+            # macos-13,
+            ubuntu-latest,
+          ]
     runs-on: ${{ matrix.os }}
     defaults:
       run: