diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 0933536..3161027 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -17,7 +17,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@v6
-      - uses: "opensafely-core/setup-action@v1"
+      - uses: "opensafely-core/setup-action@v1.6.1"
         with:
           install-uv: true
           install-just: true
@@ -30,7 +30,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@v6
-      - uses: "opensafely-core/setup-action@v1"
+      - uses: "opensafely-core/setup-action@v1.6.1"
         with:
           install-uv: true
           install-just: true
@@ -45,7 +45,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - uses: actions/checkout@v6
-      - uses: "opensafely-core/setup-action@v1"
+      - uses: "opensafely-core/setup-action@v1.6.1"
         with:
           install-uv: true
           install-just: true
diff --git a/.github/workflows/update-dependencies.yml b/.github/workflows/update-dependencies.yml
index c57e8e0..ac1ae0f 100644
--- a/.github/workflows/update-dependencies.yml
+++ b/.github/workflows/update-dependencies.yml
@@ -10,7 +10,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v6
-    - uses: "opensafely-core/setup-action@v1"
+    - uses: "opensafely-core/setup-action@v1.6.1"
       with:
         install-uv: true
         install-just: true