diff --git a/helper_scripts/generate_UArchConstants.sh b/helper_scripts/generate_UArchConstants.sh
index f3fee2a..b6bb985 100755
--- a/helper_scripts/generate_UArchConstants.sh
+++ b/helper_scripts/generate_UArchConstants.sh
@@ -17,17 +17,18 @@ t=`tail -n -$last $TEMPLATE_FILE`
 
  cd $EMULATOR_DIR
  make build-debian-image
+ cd -
 
-# run the Lua script that instantiates the cartesi module and 
+# run the Lua script that instantiates the cartesi module and
 # outputs the uarch constants values
-constants=$(docker run \
+constants=$(docker run --rm \
    -v`pwd`:/opt/cartesi/machine-solidity-step  \
    -w /opt/cartesi/machine-solidity-step \
-   -it cartesi/machine-emulator:devel \
+   cartesi/machine-emulator:devel \
    /opt/cartesi/machine-solidity-step/helper_scripts/generate_UArchConstants.lua)
 
 # compose the solidity file from all components
 echo -e "$h" "\n\n$constants" > $TARGET_FILE
 echo -e "$t" >> $TARGET_FILE
 
-echo "wrote $TARGET_FILE"
\ No newline at end of file
+echo "wrote $TARGET_FILE"