diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index dbdcdfb7d..6f4c617d8 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -106,6 +106,7 @@ jobs:
   test_amd64:
     name: Test (linux/amd64)
     needs: build
+    if: false
     runs-on: ubuntu-latest-8-cores
     steps:
       - name: Checkout machine emulator source code
@@ -335,15 +336,15 @@ jobs:
 
       - name: Run test scripts
         run: |
-          docker run --platform linux/arm64 --rm -t ${{ github.repository_owner }}/machine-emulator:tests /usr/share/cartesi-machine/tests/scripts/run-lua-tests.sh
+          docker run --platform linux/arm64 --rm -t -e "CARTESI_CONCURRENCY_UPDATE_MERKLE_TREE=1" ${{ github.repository_owner }}/machine-emulator:tests /usr/share/cartesi-machine/tests/scripts/run-lua-tests.sh
 
       - name: Run grpc lua test scripts
         run: |
-          docker run --platform linux/arm64 --rm -t ${{ github.repository_owner }}/machine-emulator:tests /usr/share/cartesi-machine/tests/scripts/test-grpc-server.sh remote-cartesi-machine cartesi-machine cartesi-machine-tests
+          docker run --platform linux/arm64 --rm -t -e "CARTESI_CONCURRENCY_UPDATE_MERKLE_TREE=1" ${{ github.repository_owner }}/machine-emulator:tests /usr/share/cartesi-machine/tests/scripts/test-grpc-server.sh remote-cartesi-machine cartesi-machine cartesi-machine-tests
 
       - name: Run jsonrpc lua test scripts
         run: |
-          docker run --platform linux/arm64 --rm -t ${{ github.repository_owner }}/machine-emulator:tests /usr/share/cartesi-machine/tests/scripts/test-jsonrpc-server.sh jsonrpc-remote-cartesi-machine cartesi-machine cartesi-machine-tests
+          docker run --platform linux/arm64 --rm -t -e "CARTESI_CONCURRENCY_UPDATE_MERKLE_TREE=1" ${{ github.repository_owner }}/machine-emulator:tests /usr/share/cartesi-machine/tests/scripts/test-jsonrpc-server.sh jsonrpc-remote-cartesi-machine cartesi-machine cartesi-machine-tests
 
       - name: Run Merkle tree tests
         run: |