diff --git a/.forgejo/workflows/workflow.yaml b/.forgejo/workflows/workflow.yaml
index 96fac37..f352186 100644
--- a/.forgejo/workflows/workflow.yaml
+++ b/.forgejo/workflows/workflow.yaml
@@ -9,13 +9,13 @@ jobs:
   lint:
     name: Lint Code (Ruff & Pylint)
     runs-on: docker
-    container: catthehacker/ubuntu:act-latest
+    container: catthehacker/ubuntu:act-latest@sha256:70d7485966a50a639ddab37445fd27c2f0b5086ad4959ec3bba228ed394c1928
     steps:
       - name: Checkout
         uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
 
       - name: "Setup uv"
-        uses: actions/setup-uv@v5
+        uses: actions/setup-uv@22695119d769bdb6f7032ad67b9bca0ef8c4a174 # v5
         with:
           version: "latest"
           enable-cache: true
@@ -35,7 +35,7 @@ jobs:
   docs:
     name: Build Documentation (MkDocs)
     runs-on: docker
-    container: catthehacker/ubuntu:act-latest
+    container: catthehacker/ubuntu:act-latest@sha256:70d7485966a50a639ddab37445fd27c2f0b5086ad4959ec3bba228ed394c1928
     steps:
       - name: Checkout
         uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
@@ -43,7 +43,7 @@ jobs:
           fetch-depth: 0
 
       - name: "Setup uv"
-        uses: actions/setup-uv@v5
+        uses: actions/setup-uv@22695119d769bdb6f7032ad67b9bca0ef8c4a174 # v5
         with:
           version: "latest"
           enable-cache: true
@@ -54,7 +54,7 @@ jobs:
         run: uv sync --no-dev --group=documentation
 
       - name: Set environment variables
-        uses: actions/env@v2
+        uses: actions/env@1791216cd180e6578dd1d67fb8d2852b883a5f53 # v2
 
       - name: Build documentation
         run: |