diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 02b1db3..f25e1b2 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -10,7 +10,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@v6
-      - uses: "opensafely-core/setup-action@v1"
+      - uses: "opensafely-core/setup-action@v1.6.1"
         with:
           install-just: true
           install-uv: true
@@ -23,7 +23,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@v6
-      - uses: "opensafely-core/setup-action@v1"
+      - uses: "opensafely-core/setup-action@v1.6.1"
         with:
           install-just: true
       - name: Run tests
diff --git a/.github/workflows/update-dependencies.yml b/.github/workflows/update-dependencies.yml
index 912d02f..5e2102f 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-just: true
         install-uv: true
diff --git a/.github/workflows/uvmirror-check.yml b/.github/workflows/uvmirror-check.yml
index 62d29df..0883de8 100644
--- a/.github/workflows/uvmirror-check.yml
+++ b/.github/workflows/uvmirror-check.yml
@@ -14,7 +14,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@v6
-      - uses: opensafely-core/setup-action@v1
+      - uses: opensafely-core/setup-action@v1.6.1
         with:
           install-just: true
           install-uv: true