diff --git a/.github/workflows/ci-reusable.yml b/.github/workflows/ci-reusable.yml
index 28a078b6..8bfe01bb 100644
--- a/.github/workflows/ci-reusable.yml
+++ b/.github/workflows/ci-reusable.yml
@@ -95,7 +95,7 @@ jobs:
           node-version: 18.15
 
       - name: Install Ethereum node dependencies
-        if: matrix.tests == 'contract' || matrix.tests == 'integration' || matrix.tests == 'integration-parallel' || matrix.tests == 'tools' || matrix.tests == 'all'
+        if: matrix.tests == 'contract' || matrix.tests == 'integration' || matrix.tests == 'tools' || matrix.tests == 'all'
         working-directory: vendor/codex-contracts-eth
         env:
           MSYS2_PATH_TYPE: inherit
@@ -117,18 +117,14 @@ jobs:
 
       ## Part 3 Tests ##
       - name: Integration tests
-        if: (matrix.tests == 'integration' || matrix.tests == 'all') && matrix.tests != 'integration-parallel'
-        run: make -j${ncpu} PARALLEL=0 testIntegration
-
-      - name: Parallel integration tests
-        if: (matrix.tests == 'integration-parallel' || matrix.tests == 'all') && matrix.tests != 'integration'
+        if: matrix.tests == 'integration' || matrix.tests == 'all'
         run: make -j${ncpu} PARALLEL=${{ env.PARALLEL }} DEBUG=${{ runner.debug }} testIntegration
 
       - name: Upload integration tests log files
         uses: actions/upload-artifact@v4
-        if: (matrix.tests == 'integration' || matrix.tests == 'integration-parallel' || matrix.tests == 'all') && always()
+        if: (matrix.tests == 'integration' || matrix.tests == 'all') && always()
         with:
-          name: ${{ matrix.os }}-${{ matrix.cpu }}-${{ matrix.nim_version }}-integration-tests-logs
+          name: ${{ matrix.os }}-${{ matrix.cpu }}-${{ matrix.nim_version }}-${{ matrix.tests }}-tests-logs
           path: tests/integration/logs/
           retention-days: 1
 
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6934e323..fb86dd97 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -10,6 +10,10 @@ on:
 env:
   cache_nonce: 0 # Allows for easily busting actions/cache caches
   nim_version: v2.0.14
+  builder_integration_from_vars: true
+  builder_integration_linux: runner-node-01-linux-03-eu-hel1
+  builder_integration_macos: macos-14-large
+  builder_integration_windows: windows-latest-amd64-32vcpu
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref || github.run_id }}
@@ -17,25 +21,27 @@ concurrency:
 
 jobs:
   matrix:
+    name: Compute matrix
     runs-on: ubuntu-latest
     outputs:
       matrix: ${{ steps.matrix.outputs.matrix }}
       cache_nonce: ${{ env.cache_nonce }}
     steps:
+      - name: Compute builders
+        if: env.builder_integration_from_vars
+        run: |
+          if [[ -n "${{ vars.builder_integration_linux }}" ]]; then echo "builder_integration_linux=${{ vars.builder_integration_linux }}"; fi >> $GITHUB_ENV
+          if [[ -n "${{ vars.builder_integration_macos }}" ]]; then echo "builder_integration_macos=${{ vars.builder_integration_macos }}"; fi >> $GITHUB_ENV
+          if [[ -n "${{ vars.builder_integration_windows }}" ]]; then echo "builder_integration_windows=${{ vars.builder_integration_windows }}"; fi >> $GITHUB_ENV
+
       - name: Compute matrix
         id: matrix
         uses: fabiocaccamo/create-matrix-action@v5
         with:
           matrix: |
-            os {linux},   cpu {amd64}, builder {ubuntu-latest},               tests {integration-parallel}, nim_version {${{ env.nim_version }}}, shell {bash --noprofile --norc -e -o pipefail}
-            os {linux},   cpu {arm64}, builder {ubuntu-24.04-arm},            tests {integration-parallel}, nim_version {${{ env.nim_version }}}, shell {bash --noprofile --norc -e -o pipefail}
-            os {linux},   cpu {amd64}, builder {ubuntu-latest-amd64-16vcpu},  tests {integration-parallel}, nim_version {${{ env.nim_version }}}, shell {bash --noprofile --norc -e -o pipefail}
-            os {macos},   cpu {amd64}, builder {macos-13},                    tests {integration-parallel}, nim_version {${{ env.nim_version }}}, shell {bash --noprofile --norc -e -o pipefail}
-            os {macos},   cpu {amd64}, builder {macos-latest},                tests {integration-parallel}, nim_version {${{ env.nim_version }}}, shell {bash --noprofile --norc -e -o pipefail}
-            os {macos},   cpu {amd64}, builder {macos-14-large},              tests {integration-parallel}, nim_version {${{ env.nim_version }}}, shell {bash --noprofile --norc -e -o pipefail}
-            os {macos},   cpu {amd64}, builder {macos-14-xlarge},             tests {integration-parallel}, nim_version {${{ env.nim_version }}}, shell {bash --noprofile --norc -e -o pipefail}
-            os {windows}, cpu {amd64}, builder {windows-latest},              tests {integration-parallel}, nim_version {${{ env.nim_version }}}, shell {msys2}
-            os {windows}, cpu {amd64}, builder {windows-latest-amd64-16vcpu}, tests {integration-parallel}, nim_version {${{ env.nim_version }}}, shell {msys2}
+            os {linux},   cpu {amd64}, builder {${{ env.builder_integration_linux }}},   tests {integration}, nim_version {${{ env.nim_version }}}, shell {bash --noprofile --norc -e -o pipefail}
+            os {macos},   cpu {amd64}, builder {${{ env.builder_integration_macos }}},   tests {integration}, nim_version {${{ env.nim_version }}}, shell {bash --noprofile --norc -e -o pipefail}
+            os {windows}, cpu {amd64}, builder {${{ env.builder_integration_windows }}}, tests {integration}, nim_version {${{ env.nim_version }}}, shell {msys2}
 
   build:
     needs: matrix