diff --git a/.github/workflows/codecov.yml b/.github/workflows/codecov.yml
index bad328109..9ec980303 100644
--- a/.github/workflows/codecov.yml
+++ b/.github/workflows/codecov.yml
@@ -6,7 +6,7 @@ on:
 jobs:
   codecov:
     container: 
-      image: swift:6.3
+      image: swift:6.4
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v5
diff --git a/.github/workflows/documentation.yml b/.github/workflows/documentation.yml
index d0eefbe6c..8f32f7313 100644
--- a/.github/workflows/documentation.yml
+++ b/.github/workflows/documentation.yml
@@ -9,7 +9,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     container: 
-      image: swift:6.3
+      image: swift:6.4
 
     steps:
       - uses: actions/checkout@v5
diff --git a/.github/workflows/downstream-project.yml b/.github/workflows/downstream-project.yml
index bf20e35da..d01736b06 100644
--- a/.github/workflows/downstream-project.yml
+++ b/.github/workflows/downstream-project.yml
@@ -10,7 +10,7 @@ jobs:
       fail-fast: false
       matrix:
         image:
-          - swift:6.3-noble
+          - swift:6.4-noble
           - swiftlang/swift:nightly-noble
         flags:
           - []
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 0e22960f7..420fb4d28 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -17,6 +17,8 @@ jobs:
           - swift:6.2-noble
           - swift:6.3-jammy
           - swift:6.3-noble
+          - swift:6.4-jammy
+          - swift:6.4-noble
           - swiftlang/swift:nightly-focal
           - swiftlang/swift:nightly-jammy
     container: ${{ matrix.image }}
diff --git a/.github/workflows/traits.yml b/.github/workflows/traits.yml
index 019d4c845..fb884f760 100644
--- a/.github/workflows/traits.yml
+++ b/.github/workflows/traits.yml
@@ -6,7 +6,7 @@ on:
 jobs:
   without-default-traits:
     container: 
-      image: swift:6.3
+      image: swift:6.4
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v5