diff --git a/.github/workflows/ci-build.yml b/.github/workflows/ci-build.yml
index d1cd1b3a9..c86de1d80 100644
--- a/.github/workflows/ci-build.yml
+++ b/.github/workflows/ci-build.yml
@@ -16,7 +16,7 @@ env:
 jobs:
   build:
     name: Build
-    runs-on: macos-latest
+    runs-on: macos-11
 
     steps:
       - uses: actions/checkout@v2
diff --git a/.github/workflows/ci-tests.yml b/.github/workflows/ci-tests.yml
index eac0c885d..65846be15 100644
--- a/.github/workflows/ci-tests.yml
+++ b/.github/workflows/ci-tests.yml
@@ -16,7 +16,7 @@ env:
 jobs:
   tests:
     name: Tests
-    runs-on: macos-latest
+    runs-on: macos-11
 
     steps:
       - uses: actions/checkout@v2
diff --git a/changelog.d/pr-4998.build b/changelog.d/pr-4998.build
new file mode 100644
index 000000000..6b36ac81e
--- /dev/null
+++ b/changelog.d/pr-4998.build
@@ -0,0 +1 @@
+Build: Update to Xcode 12.5 in the Fastfile and macOS 11 in the GitHub actions.
\ No newline at end of file