diff --git a/.github/workflows/catalog-sync-check.yml b/.github/workflows/catalog-sync-check.yml
index e108764ed..c25a96efa 100644
--- a/.github/workflows/catalog-sync-check.yml
+++ b/.github/workflows/catalog-sync-check.yml
@@ -6,6 +6,10 @@ on:
   pull_request:
     branches: [ main ]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   validate-catalog:
     runs-on: ubuntu-latest
@@ -18,6 +22,7 @@ jobs:
       uses: actions/setup-python@v5
       with:
         python-version: '3.11'
+        cache: "pip"
 
     - name: Run Catalog Validation Script
       run: python scripts/validate_plugins_catalog.py
\ No newline at end of file
diff --git a/.github/workflows/check-artifacts.yml b/.github/workflows/check-artifacts.yml
index 7f520594d..3a5d708d1 100644
--- a/.github/workflows/check-artifacts.yml
+++ b/.github/workflows/check-artifacts.yml
@@ -12,6 +12,10 @@ on:
       - "scripts/check-artifacts.sh"
       - ".github/workflows/check-artifacts.yml"
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   artifact-check:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d6ed9d78b..28fa4e7e6 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -4,6 +4,10 @@ on:
   push:
   pull_request:
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 permissions:
   contents: read
 
@@ -21,6 +25,7 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: "3.11"
+          cache: "pip"
       - name: Fetch base branch for diff
         if: github.event_name == 'pull_request'
         run: git fetch origin "${{ github.base_ref }}" --depth=1
@@ -50,6 +55,7 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.11"
+          cache: "pip"
       - name: Validate issue template labels
         run: python scripts/validate_issue_template_labels.py
 
@@ -60,6 +66,7 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.11"
+          cache: "pip"
 
       - name: Validate documentation anchors
         run: python scripts/validate_doc_anchors.py
@@ -73,6 +80,7 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.11"
+          cache: "pip"
       - name: Install backend system dependencies
         run: sudo apt-get update && sudo apt-get install -y libcairo2-dev pkg-config
       - name: Install backend development dependencies
@@ -95,6 +103,7 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.11"
+          cache: "pip"
       - name: Install backend system dependencies
         run: sudo apt-get update && sudo apt-get install -y libcairo2-dev pkg-config
       - name: Install backend dependencies
@@ -117,6 +126,7 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.11"
+          cache: "pip"
       - name: Install backend system dependencies
         run: sudo apt-get update && sudo apt-get install -y libcairo2-dev pkg-config
       - name: Install backend dependencies
@@ -146,6 +156,7 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.11"
+          cache: "pip"
       - name: Install backend system dependencies
         run: sudo apt-get update && sudo apt-get install -y libcairo2-dev pkg-config
       - name: Install backend dependencies
@@ -177,6 +188,7 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.11"
+          cache: "pip"
       - name: Install backend system dependencies
         run: sudo apt-get update && sudo apt-get install -y libcairo2-dev pkg-config
       - name: Install backend dependencies
@@ -226,6 +238,7 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.11"
+          cache: "pip"
       - name: Install backend system dependencies
         run: sudo apt-get update && sudo apt-get install -y libcairo2-dev pkg-config
       - name: Install backend dependencies
diff --git a/.github/workflows/docker-hardening.yml b/.github/workflows/docker-hardening.yml
index 412c7c763..b28412867 100644
--- a/.github/workflows/docker-hardening.yml
+++ b/.github/workflows/docker-hardening.yml
@@ -15,6 +15,10 @@ on:
       - ".github/workflows/docker-hardening.yml"
   workflow_dispatch:
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   build:
     name: Build ${{ matrix.service }} image
diff --git a/.github/workflows/plugin-integrity-check.yml b/.github/workflows/plugin-integrity-check.yml
index 66160744b..a4bba187b 100644
--- a/.github/workflows/plugin-integrity-check.yml
+++ b/.github/workflows/plugin-integrity-check.yml
@@ -8,6 +8,10 @@ on:
       - 'scripts/refresh_plugin_checksum.py'
       - 'backend/secuscan/plugins.py'
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   parser-integrity:
     runs-on: ubuntu-latest
@@ -20,6 +24,7 @@ jobs:
       uses: actions/setup-python@v5
       with:
         python-version: '3.11'
+        cache: "pip"
 
     - name: Verify all plugin parser hashes match metadata
       run: |
diff --git a/.github/workflows/security-ci.yml b/.github/workflows/security-ci.yml
index 8abb80e22..a6d134d75 100644
--- a/.github/workflows/security-ci.yml
+++ b/.github/workflows/security-ci.yml
@@ -6,6 +6,10 @@ on:
   pull_request:
     branches: [main]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 permissions:
   contents: read
   security-events: write
@@ -19,6 +23,7 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.11"
+          cache: "pip"
       - name: Install bandit
         run: pip install bandit[toml]
       - name: Run bandit security linter
@@ -52,6 +57,7 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.11"
+          cache: "pip"
       - name: Check all API routers have authentication
         run: |
           python -c "
@@ -86,6 +92,7 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.11"
+          cache: "pip"
       - name: Verify debug mode is off by default
         run: |
           python -c "
@@ -176,6 +183,7 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.11"
+          cache: "pip"
       - name: Validate .env.example safe defaults
         run: |
           python -c "
@@ -209,6 +217,7 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.11"
+          cache: "pip"
       - name: Install pip-audit
         run: pip install pip-audit
       - name: Audit Python dependencies
diff --git a/.github/workflows/smoke-test.yml b/.github/workflows/smoke-test.yml
index 491a16a19..e419f2d8e 100644
--- a/.github/workflows/smoke-test.yml
+++ b/.github/workflows/smoke-test.yml
@@ -27,6 +27,10 @@ on:
       - ".github/workflows/smoke-test.yml"
   workflow_dispatch:
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   shell-smoke:
     name: start.sh shell smoke
@@ -67,6 +71,7 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: "3.11"
+          cache: "pip"
 
       # ── 3. Set up Node.js ──────────────────────────────────────────────────
       # setup.sh checks for node + npm; frontend uses Vite on port 5173.
diff --git a/.github/workflows/trivy-scan.yml b/.github/workflows/trivy-scan.yml
index 492576a02..0521466d6 100644
--- a/.github/workflows/trivy-scan.yml
+++ b/.github/workflows/trivy-scan.yml
@@ -21,6 +21,10 @@ on:
     - cron: "0 6 * * 1"
   workflow_dispatch:
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 permissions:
   contents: read
   security-events: write