diff --git a/.github/workflows/continuous-integration.yaml b/.github/workflows/continuous-integration.yaml
index 3de54834e..d18eb6f58 100644
--- a/.github/workflows/continuous-integration.yaml
+++ b/.github/workflows/continuous-integration.yaml
@@ -34,15 +34,15 @@ jobs:
 
     steps:
       - name: Checkout Code
-        uses: actions/checkout@v2
+        uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
         with:
           fetch-depth: 0
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@dc73133d4da04e56a135ae2246682783cc7c7cb6
         with:
           python-version: ${{ matrix.python-version }}
       - name: Cache Installation Files
-        uses: actions/cache@v2
+        uses: actions/cache@c64c572235d810460d0d6876e9c705ad5002b353
         with:
           # Paths are Unix specific for now
           path: |
@@ -73,7 +73,7 @@ jobs:
           make --keep-going pcc docs
       - name: Archive docs artifacts
         if: ${{ steps.conformance.outcome == 'success' && !cancelled() }}
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@27121b0bdffd731efa15d66772be8dc71245d074
         with:
           name: html-docs
           path: docs/_build/html
@@ -98,13 +98,13 @@ jobs:
         run: |
           ./script/actions_utils/coverage.sh ${{ github.base_ref }}
       - name: Archive test coverage
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@27121b0bdffd731efa15d66772be8dc71245d074
         if: ${{ steps.coverage.outcome != 'skipped' && !cancelled() }}
         with:
           name: coverage
           path: coverage.html
       - name: Comment with coverage
-        uses: marocchino/sticky-pull-request-comment@v2
+        uses: marocchino/sticky-pull-request-comment@82e7a0d3c51217201b3fedc4ddde6632e969a477
         if: ${{ steps.coverage.outcome != 'skipped' && !cancelled() }}
         with:
           path: diff-coverage.txt
@@ -121,7 +121,7 @@ jobs:
       - name: Slack Notification
         if: ${{ always() }}
         continue-on-error: true
-        uses: rtCamp/action-slack-notify@v2
+        uses: rtCamp/action-slack-notify@12e36fc18b0689399306c2e0b3e0f2978b7f1ee7
         env:
           SLACK_CHANNEL: ${{ secrets.SLACK_CHANNEL }}
           SLACK_ICON: https://pbs.twimg.com/profile_images/1274014582265298945/OjBKP9kn_400x400.png
@@ -139,14 +139,14 @@ jobs:
     steps:
       - name: Download Documentation
         id: download
-        uses: actions/download-artifact@v2
+        uses: actions/download-artifact@3be87be14a055c47b01d3bd88f8fe02320a9bb60
         with:
           name: html-docs
 
       - name: Publish Documentation to S3
         id: publish
         if: ${{ steps.download.outcome == 'success' && !cancelled() }}
-        uses: jakejarvis/s3-sync-action@master
+        uses: jakejarvis/s3-sync-action@be0c4ab89158cac4278689ebedd8407dd5f35a83
         with:
           args: --delete
         env:
@@ -158,7 +158,7 @@ jobs:
 
       - name: Invalidate CloudFront Cache
         if: ${{ steps.publish.outcome == 'success' }}
-        uses: awact/cloudfront-action@master
+        uses: awact/cloudfront-action@8bcfabc7b4bbc0cb8e55e48527f0e3a6d681627c
         env:
           SOURCE_PATH: '/*'
           AWS_REGION: ${{ secrets.AWS_REGION }}
@@ -169,7 +169,7 @@ jobs:
       - name: Slack Notification
         if: ${{ always() }}
         continue-on-error: true
-        uses: rtCamp/action-slack-notify@v2
+        uses: rtCamp/action-slack-notify@12e36fc18b0689399306c2e0b3e0f2978b7f1ee7
         env:
           SLACK_CHANNEL: ${{ secrets.SLACK_CHANNEL }}
           SLACK_ICON: https://pbs.twimg.com/profile_images/1274014582265298945/OjBKP9kn_400x400.png
diff --git a/.github/workflows/docker-env.yaml b/.github/workflows/docker-env.yaml
index f597bace2..9bf13f421 100644
--- a/.github/workflows/docker-env.yaml
+++ b/.github/workflows/docker-env.yaml
@@ -33,20 +33,20 @@ jobs:
     runs-on: ubuntu-20.04
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
 
       - name: Set up Docker Buildx
         id: buildx
-        uses: docker/setup-buildx-action@v1
+        uses: docker/setup-buildx-action@94ab11c41e45d028884a99163086648e898eed25
       - name: Login to GitHub Container Registry
-        uses: docker/login-action@v1
+        uses: docker/login-action@f054a8b539a109f9f41c372932f1ae047eff08c9
         with:
           registry: ghcr.io
           username: ${{ secrets.BOT_USERNAME }}
           password: ${{ secrets.BOT_TOKEN }}
       - name: Build concretefhe-env Image
         if: ${{ success() && !cancelled() }}
-        uses: docker/build-push-action@v2
+        uses: docker/build-push-action@a66e35b9cbcf4ad0ea91ffcaf7bbad63ad9e0229
         with:
           context: .
           builder: ${{ steps.buildx.outputs.name }}
@@ -66,7 +66,7 @@ jobs:
       - name: Slack Notification
         if: ${{ always() }}
         continue-on-error: true
-        uses: rtCamp/action-slack-notify@v2
+        uses: rtCamp/action-slack-notify@12e36fc18b0689399306c2e0b3e0f2978b7f1ee7
         env:
           SLACK_CHANNEL: ${{ secrets.SLACK_CHANNEL }}
           SLACK_ICON: https://pbs.twimg.com/profile_images/1274014582265298945/OjBKP9kn_400x400.png
@@ -96,7 +96,7 @@ jobs:
             exit 1
           fi
       - name: Login to GitHub Container Registry
-        uses: docker/login-action@v1
+        uses: docker/login-action@f054a8b539a109f9f41c372932f1ae047eff08c9
         with:
           registry: ghcr.io
           username: ${{ secrets.BOT_USERNAME }}
@@ -116,7 +116,7 @@ jobs:
       - name: Slack Notification
         if: ${{ always() }}
         continue-on-error: true
-        uses: rtCamp/action-slack-notify@v2
+        uses: rtCamp/action-slack-notify@12e36fc18b0689399306c2e0b3e0f2978b7f1ee7
         env:
           SLACK_CHANNEL: ${{ secrets.SLACK_CHANNEL }}
           SLACK_ICON: https://pbs.twimg.com/profile_images/1274014582265298945/OjBKP9kn_400x400.png
diff --git a/.github/workflows/package-watcher.yaml b/.github/workflows/package-watcher.yaml
index d0ca3444d..f01f7d4c7 100644
--- a/.github/workflows/package-watcher.yaml
+++ b/.github/workflows/package-watcher.yaml
@@ -13,7 +13,7 @@ jobs:
     runs-on: ubuntu-20.04
     steps:
       - name: Checkout Code
-        uses: actions/checkout@v2
+        uses: actions/checkout@5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f
       - name: Compare image timestamps and notify
         run: |
           ./script/actions_utils/container_timestamp_check.sh \