diff --git a/.github/workflows/anchor-drift.yml b/.github/workflows/anchor-drift.yml
index 73def34..6233ccf 100644
--- a/.github/workflows/anchor-drift.yml
+++ b/.github/workflows/anchor-drift.yml
@@ -20,7 +20,7 @@ jobs:
   membership-integrity:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262  # v4
       - name: Check membership manifest and submodule declarations
         run: scripts/check-membership.sh
       - name: Resolve submodule pins
@@ -50,7 +50,7 @@ jobs:
   upstream-pins:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262  # v4
       - name: Check upstream spec and governance pins
         run: |
           anchor=".machine_readable/anchors/ANCHOR.a2ml"
@@ -67,7 +67,7 @@ jobs:
   governance-validation:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262  # v4
       - uses: hyperpolymath/a2ml-ecosystem/validate-action@aa4b836bd969df2bc58128cb8e3d20bbc88d5e79
         with:
           path: "."
diff --git a/gleam/.github/workflows/test.yml b/gleam/.github/workflows/test.yml
index 209358c..a28ec09 100644
--- a/gleam/.github/workflows/test.yml
+++ b/gleam/.github/workflows/test.yml
@@ -13,7 +13,7 @@ jobs:
     timeout-minutes: 30
     steps:
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
-      - uses: erlef/setup-beam@v1
+      - uses: erlef/setup-beam@54075bcc5e249e4758d363f27d099f55d843f124  # v1
         with:
           otp-version: "28"
           gleam-version: "1.14.0"