diff --git a/.github/actions/bootstrap/action.yml b/.github/actions/bootstrap/action.yml
index 33355c13348..33c88aeb5a0 100644
--- a/.github/actions/bootstrap/action.yml
+++ b/.github/actions/bootstrap/action.yml
@@ -12,6 +12,9 @@ inputs:
 runs:
   using: "composite"
   steps:
+    - name: Setup Namespace Cache
+      uses: ./.github/actions/namespace_cache
+
     - name: Install rust.
       uses: ./.github/actions/install_rust
       with:
diff --git a/.github/actions/install_rust/action.yml b/.github/actions/install_rust/action.yml
index 26b78ef400c..8ed4935869d 100644
--- a/.github/actions/install_rust/action.yml
+++ b/.github/actions/install_rust/action.yml
@@ -12,11 +12,6 @@ inputs:
 runs:
   using: "composite"
   steps:
-    - name: Mount Namespace cache volume
-      uses: namespacelabs/nscloud-cache-action@v1
-      with:
-        path: /home/runner/.cargo
-
     - uses: moonrepo/setup-rust@v1
       name: Install Rust toolchain and binaries
       with:
diff --git a/.github/actions/namespace_cache/action.yaml b/.github/actions/namespace_cache/action.yaml
new file mode 100644
index 00000000000..5df0dcadc14
--- /dev/null
+++ b/.github/actions/namespace_cache/action.yaml
@@ -0,0 +1,15 @@
+name: "Setup Namespace Cache"
+description: "Use Namespace actions to setup cache"
+
+runs:
+  using: "composite"
+  steps:
+    - name: Mount namespace cache volume for rust
+      uses: namespacelabs/nscloud-cache-action@v1
+      with:
+        path: /home/runner/.cargo
+
+    - name: Mount namespace cache volume for python
+      uses: namespacelabs/nscloud-cache-action@v1
+      with:
+        cache: python
diff --git a/.github/actions/setup_native_deps/action.yml b/.github/actions/setup_native_deps/action.yml
index f8e53180f91..24eba1c4ca2 100644
--- a/.github/actions/setup_native_deps/action.yml
+++ b/.github/actions/setup_native_deps/action.yml
@@ -1,11 +1,6 @@
 name: "Setup Cairo Native Dependencies"
 description: "Sets up LLVM and GMP libraries"
 
-outputs:
-  cairo-native-runtime-library:
-    description: "The path to the cairo native runtime library"
-    value: ${{ steps.set-env-vars.outputs.cairo-native-runtime-library }}
-
 runs:
   using: "composite"
   steps:
diff --git a/.github/workflows/blockifier_ci.yml b/.github/workflows/blockifier_ci.yml
index d9074df0149..dc8b66a3139 100644
--- a/.github/workflows/blockifier_ci.yml
+++ b/.github/workflows/blockifier_ci.yml
@@ -40,7 +40,7 @@ jobs:
   test-without-features:
     runs-on: namespace-profile-medium-ubuntu-24-04-amd64
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: ./.github/actions/bootstrap
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
@@ -51,7 +51,7 @@ jobs:
   test-with-transaction-serde-feature:
     runs-on: namespace-profile-medium-ubuntu-24-04-amd64
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: ./.github/actions/bootstrap
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
@@ -60,9 +60,9 @@ jobs:
       - run: cargo build -p blockifier --features transaction_serde
 
   test-with-cairo-native-feature:
-    runs-on: namespace-profile-medium-ubuntu-24-04-amd64
+    runs-on: namespace-profile-large-ubuntu-24-04-amd64
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: ./.github/actions/bootstrap
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
@@ -73,7 +73,7 @@ jobs:
   test-with-tracing-feature:
     runs-on: namespace-profile-medium-ubuntu-24-04-amd64
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: ./.github/actions/bootstrap
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
@@ -82,11 +82,11 @@ jobs:
       - run: cargo test -p blockifier --features tracing
 
   benchmarking:
-    runs-on: namespace-profile-medium-ubuntu-24-04-amd64
+    runs-on: namespace-profile-xlarge-ubuntu-24-04-amd64
     if: ${{ github.event_name == 'pull_request' }}
     steps:
       # Checkout the base branch to benchmark the old code.
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           ref: ${{ github.base_ref }}
 
@@ -94,24 +94,26 @@ jobs:
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
 
-      # Restore cargo artifacts build cache.
-      - name: Restore Cargo build cache
-        uses: Swatinem/rust-cache@v2
-        with:
-          shared-key: blockifier-bench
-          cache-on-failure: true
-          cache-workspace-crates: true
-
       # Benchmark the base branch code.
-      - run: cargo run -p bench_tools -- run --package blockifier --out /tmp/base_results
+      - name: Benchmark (Base Branch)
+        run: cargo run -p bench_tools -- run --package blockifier --out /tmp/base_results
 
-      # Checkout the current branch to benchmark the new code.
-      - uses: actions/checkout@v4
+      # Checkout the PR branch into a unique subdirectory to avoid overwriting
+      # the base branch's composite action files at the workspace root, and to
+      # avoid colliding with any repo folder (e.g. one named "pr").
+      - uses: actions/checkout@v6
         with:
-          clean: false
+          path: pr-${{ github.run_id }}
 
-      # Benchmark the current branch and compare to the previous run.
+      # Copy base branch Criterion baseline into PR dir so run-and-compare finds it.
       - run: |
+          mkdir -p pr-${{ github.run_id }}/target
+          cp -r target/criterion pr-${{ github.run_id }}/target/
+
+      # Benchmark the current branch and compare to the previous run.
+      - name: Benchmark (Feature Branch)
+        working-directory: pr-${{ github.run_id }}
+        run: |
           cargo run -p bench_tools -- run-and-compare \
             --package blockifier \
             --out /tmp/new_results \
diff --git a/.github/workflows/blockifier_compiled_cairo.yml b/.github/workflows/blockifier_compiled_cairo.yml
index a1b7ad981e7..fe1bce56c3b 100644
--- a/.github/workflows/blockifier_compiled_cairo.yml
+++ b/.github/workflows/blockifier_compiled_cairo.yml
@@ -29,7 +29,7 @@ jobs:
   verify_cairo_file_dependencies:
     runs-on: namespace-profile-medium-ubuntu-24-04-amd64
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: ./.github/actions/bootstrap
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
@@ -39,7 +39,6 @@ jobs:
         id: setup-pypy
         with:
           python-version: "pypy3.9"
-          cache: "pip"
       - run: ln -s '${{ steps.setup-pypy.outputs.python-path }}' /usr/local/bin/pypy3.9
       - env:
           LD_LIBRARY_PATH: ${{ env.Python3_ROOT_DIR }}/bin
diff --git a/.github/workflows/blockifier_reexecution_ci.yml b/.github/workflows/blockifier_reexecution_ci.yml
index b3135c96b7d..7f8dc6794dc 100644
--- a/.github/workflows/blockifier_reexecution_ci.yml
+++ b/.github/workflows/blockifier_reexecution_ci.yml
@@ -34,7 +34,7 @@ jobs:
   blockifier_reexecution:
     runs-on: namespace-profile-medium-ubuntu-24-04-amd64
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: ./.github/actions/bootstrap
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
diff --git a/.github/workflows/committer_and_os_cli_push.yml b/.github/workflows/committer_and_os_cli_push.yml
index 4d01ded8d54..6565f530de3 100644
--- a/.github/workflows/committer_and_os_cli_push.yml
+++ b/.github/workflows/committer_and_os_cli_push.yml
@@ -45,7 +45,7 @@ jobs:
   gcs-push:
     runs-on: namespace-profile-medium-ubuntu-24-04-amd64
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: ./.github/actions/bootstrap
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
@@ -70,7 +70,6 @@ jobs:
         id: setup-pypy
         with:
           python-version: "pypy3.9"
-          cache: "pip"
       - run: ln -s '${{ steps.setup-pypy.outputs.python-path }}' /usr/local/bin/pypy3.9
       - env:
           LD_LIBRARY_PATH: ${{ env.Python3_ROOT_DIR }}/bin
diff --git a/.github/workflows/committer_ci.yml b/.github/workflows/committer_ci.yml
index db97ff4ca44..dbc89379125 100644
--- a/.github/workflows/committer_ci.yml
+++ b/.github/workflows/committer_ci.yml
@@ -54,7 +54,11 @@ jobs:
     runs-on: namespace-profile-medium-ubuntu-24-04-amd64
     if: ${{ github.event_name == 'pull_request' }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
+
+      - uses: ./.github/actions/bootstrap
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
 
       # Setup pypy and link to the location expected by .cargo/config.toml.
       # Python + requirements are needed to compile the OS.
@@ -62,16 +66,12 @@ jobs:
         id: setup-pypy
         with:
           python-version: "pypy3.9"
-          cache: "pip"
       - run: ln -s '${{ steps.setup-pypy.outputs.python-path }}' /usr/local/bin/pypy3.9
       - env:
           LD_LIBRARY_PATH: ${{ env.Python3_ROOT_DIR }}/bin
         run: echo "LD_LIBRARY_PATH=${LD_LIBRARY_PATH}" >> $GITHUB_ENV
       - run: pip install -r scripts/requirements.txt
 
-      - uses: ./.github/actions/bootstrap
-        with:
-          github_token: ${{ secrets.GITHUB_TOKEN }}
 
       - id: auth
         uses: "google-github-actions/auth@v2"
@@ -101,34 +101,33 @@ jobs:
       # PR-only: Checkout the base branch to benchmark the old code.
       - name: Checkout base branch (PR only)
         if: github.event_name == 'pull_request'
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           ref: ${{ github.base_ref }}
 
       # Push/dispatch: Checkout the specified or current branch.
       - name: Checkout repository (push/dispatch)
         if: github.event_name != 'pull_request'
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           ref: ${{ inputs.branch || github.ref }}
 
+      - uses: ./.github/actions/bootstrap
+        with:
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+
       # Setup pypy and link to the location expected by .cargo/config.toml.
       # Python + requirements are needed to compile the OS.
       - uses: actions/setup-python@v5
         id: setup-pypy
         with:
           python-version: "pypy3.9"
-          cache: "pip"
       - run: ln -s '${{ steps.setup-pypy.outputs.python-path }}' /usr/local/bin/pypy3.9
       - env:
           LD_LIBRARY_PATH: ${{ env.Python3_ROOT_DIR }}/bin
         run: echo "LD_LIBRARY_PATH=${LD_LIBRARY_PATH}" >> $GITHUB_ENV
       - run: pip install -r scripts/requirements.txt
 
-      - uses: ./.github/actions/bootstrap
-        with:
-          github_token: ${{ secrets.GITHUB_TOKEN }}
-
       # Auth with GCS for bench_tools to download inputs.
       - id: auth
         uses: "google-github-actions/auth@v2"
@@ -146,22 +145,32 @@ jobs:
         if: github.event_name == 'pull_request'
         run: cp -r crates/starknet_committer_and_os_cli/test_inputs /tmp/test_inputs
 
-      # PR-only: Checkout the current branch to benchmark the new code.
+      # PR-only: Checkout the current branch into a subdirectory to avoid overwriting
+      # the base branch's composite action files at the workspace root.
       - name: Checkout current branch (PR only)
         if: github.event_name == 'pull_request'
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
-          clean: false
+          path: pr-${{ github.run_id }}
+
+      # PR-only: Copy base branch Criterion baseline into PR dir so run-and-compare finds it.
+      - name: Copy Criterion baseline (PR only)
+        if: github.event_name == 'pull_request'
+        run: |
+          mkdir -p pr-${{ github.run_id }}/target
+          cp -r target/criterion pr-${{ github.run_id }}/target/
 
       # PR-only: Re-install pip requirements in case they changed between branches.
       - name: Re-install pip requirements (PR only)
         if: github.event_name == 'pull_request'
+        working-directory: pr-${{ github.run_id }}
         run: pip install -r scripts/requirements.txt
 
       # PR-only: Benchmark the current branch and compare to the previous run.
       # Use the saved inputs and enforce absolute time limits and regression limit.
       - name: Benchmark and compare (PR only)
         if: github.event_name == 'pull_request'
+        working-directory: pr-${{ github.run_id }}
         run: |
           cargo run -p bench_tools -- run-and-compare \
             --package starknet_committer_and_os_cli \
diff --git a/.github/workflows/hybrid_system_test.yaml b/.github/workflows/hybrid_system_test.yaml
index 93f7d00d366..e57916491b4 100644
--- a/.github/workflows/hybrid_system_test.yaml
+++ b/.github/workflows/hybrid_system_test.yaml
@@ -38,7 +38,7 @@ jobs:
     outputs:
       should_run: ${{ github.event_name == 'workflow_dispatch' && 'true' || steps.system_check.outputs.should_run }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         if: github.event_name != 'workflow_dispatch'
         with:
           fetch-depth: 0
@@ -92,7 +92,7 @@ jobs:
           - svc: dummy_eth_to_strk_oracle
             dockerfile: dummy_eth_to_strk_oracle.Dockerfile
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Build ${{ matrix.svc }} image remotely
         uses: docker/build-push-action@v6.18.0
@@ -109,7 +109,7 @@ jobs:
     timeout-minutes: 45
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Create registries.yaml for nscr.io
         run: |
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 0a5dd080c96..298d1751785 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -25,7 +25,7 @@ jobs:
     timeout-minutes: 30
     steps:
       # Environment setup.
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           # Fetch the entire history. Required to checkout the merge target commit, so the diff can
           # be computed.
@@ -42,7 +42,6 @@ jobs:
         id: setup-pypy
         with:
           python-version: "pypy3.9"
-          cache: "pip"
       - run: ln -s '${{ steps.setup-pypy.outputs.python-path }}' /usr/local/bin/pypy3.9
       - env:
           LD_LIBRARY_PATH: ${{ env.Python3_ROOT_DIR }}/bin
@@ -80,7 +79,7 @@ jobs:
     runs-on: namespace-profile-medium-ubuntu-24-04-amd64
     timeout-minutes: 30
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: ./.github/actions/bootstrap
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
@@ -90,7 +89,7 @@ jobs:
     runs-on: namespace-profile-xlarge-ubuntu-24-04-amd64
     timeout-minutes: 45
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           # Fetch the entire history.
           fetch-depth: 0
@@ -103,7 +102,6 @@ jobs:
         id: setup-pypy
         with:
           python-version: "pypy3.9"
-          cache: "pip"
       - run: ln -s '${{ steps.setup-pypy.outputs.python-path }}' /usr/local/bin/pypy3.9
       - env:
           LD_LIBRARY_PATH: ${{ env.Python3_ROOT_DIR }}/bin
@@ -120,7 +118,7 @@ jobs:
     runs-on: namespace-profile-large-ubuntu-24-04-amd64
     timeout-minutes: 45
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           # Fetch the entire history.
           fetch-depth: 0
@@ -133,7 +131,6 @@ jobs:
         id: setup-pypy
         with:
           python-version: "pypy3.9"
-          cache: "pip"
       - run: ln -s '${{ steps.setup-pypy.outputs.python-path }}' /usr/local/bin/pypy3.9
       - env:
           LD_LIBRARY_PATH: ${{ env.Python3_ROOT_DIR }}/bin
@@ -151,7 +148,7 @@ jobs:
     runs-on: namespace-profile-medium-ubuntu-24-04-amd64
     timeout-minutes: 10
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: ./.github/actions/bootstrap
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
diff --git a/.github/workflows/main_nightly.yml b/.github/workflows/main_nightly.yml
index 35564561d67..3eee1853bad 100644
--- a/.github/workflows/main_nightly.yml
+++ b/.github/workflows/main_nightly.yml
@@ -24,7 +24,7 @@ jobs:
       matrix:
         branch: ${{ fromJson(needs.define_branches.outputs.branches) }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           ref: ${{ matrix.branch }}
 
@@ -56,7 +56,7 @@ jobs:
       matrix:
         branch: ${{ fromJson(needs.define_branches.outputs.branches) }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           ref: ${{ matrix.branch }}
 
diff --git a/.github/workflows/main_pr.yml b/.github/workflows/main_pr.yml
index e0d31885c37..de2c390bac9 100644
--- a/.github/workflows/main_pr.yml
+++ b/.github/workflows/main_pr.yml
@@ -25,7 +25,7 @@ jobs:
   commitlint:
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           fetch-depth: 0
 
diff --git a/.github/workflows/merge_queue_ci.yml b/.github/workflows/merge_queue_ci.yml
index 4e8f8eb075d..6fe8b1ca2aa 100644
--- a/.github/workflows/merge_queue_ci.yml
+++ b/.github/workflows/merge_queue_ci.yml
@@ -16,7 +16,7 @@ jobs:
     runs-on: namespace-profile-medium-ubuntu-24-04-amd64
     steps:
       # Environment setup.
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       # Install rust components + lld.
       - uses: ./.github/actions/bootstrap
@@ -29,7 +29,6 @@ jobs:
         id: setup-pypy
         with:
           python-version: "pypy3.9"
-          cache: "pip"
       - run: ln -s '${{ steps.setup-pypy.outputs.python-path }}' /usr/local/bin/pypy3.9
       - env:
           LD_LIBRARY_PATH: ${{ env.Python3_ROOT_DIR }}/bin
diff --git a/.github/workflows/sequencer_cdk8s-test.yml b/.github/workflows/sequencer_cdk8s-test.yml
index c2a98db918b..adef2e6fde2 100644
--- a/.github/workflows/sequencer_cdk8s-test.yml
+++ b/.github/workflows/sequencer_cdk8s-test.yml
@@ -25,7 +25,7 @@ jobs:
 
     steps:
       - name: Checkout sequencer
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Setup python
         uses: actions/setup-python@v5.4.0
diff --git a/.github/workflows/sequencer_docker-publish.yml b/.github/workflows/sequencer_docker-publish.yml
index ddac541c5db..635fbcf1824 100644
--- a/.github/workflows/sequencer_docker-publish.yml
+++ b/.github/workflows/sequencer_docker-publish.yml
@@ -22,7 +22,7 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       # Login to a Docker registry except on PR
       # https://github.com/docker/login-action
diff --git a/.github/workflows/upload_artifacts_workflow.yml b/.github/workflows/upload_artifacts_workflow.yml
index b98aca2e854..8dd5c3e9f9f 100644
--- a/.github/workflows/upload_artifacts_workflow.yml
+++ b/.github/workflows/upload_artifacts_workflow.yml
@@ -50,7 +50,7 @@ jobs:
   native-blockifier-artifacts-push:
     runs-on: namespace-profile-medium-ubuntu-24-04-amd64
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       # Commit hash on pull request event would be the head commit of the branch.
       - name: Get commit hash prefix for PR update
diff --git a/.github/workflows/verify-deps.yml b/.github/workflows/verify-deps.yml
index d671d61fdfa..46305280293 100644
--- a/.github/workflows/verify-deps.yml
+++ b/.github/workflows/verify-deps.yml
@@ -12,7 +12,7 @@ jobs:
     name: Latest Dependencies
     runs-on: namespace-profile-medium-ubuntu-24-04-amd64
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: ./.github/actions/bootstrap
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}