diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index dbdcdfb7d..dff77adc6 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
@@ -335,7 +336,7 @@ 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 -e "CARTESI_CONCURRENCY_UPDATE_MERKLE_TREE=1" --rm -t ${{ github.repository_owner }}/machine-emulator:tests /usr/share/cartesi-machine/tests/scripts/run-lua-tests.sh
 
       - name: Run grpc lua test scripts
         run: |
diff --git a/tests/scripts/run-lua-tests.sh b/tests/scripts/run-lua-tests.sh
index 04eb43540..af1e177ce 100755
--- a/tests/scripts/run-lua-tests.sh
+++ b/tests/scripts/run-lua-tests.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/bash -x
 
 # Copyright Cartesi and individual authors (see AUTHORS)
 # SPDX-License-Identifier: LGPL-3.0-or-later