diff --git a/pykwasm/src/pykwasm/mkacct.py b/pykwasm/src/pykwasm/mkacct.py
index b2863876e..5684c04e0 100644
--- a/pykwasm/src/pykwasm/mkacct.py
+++ b/pykwasm/src/pykwasm/mkacct.py
@@ -3,11 +3,13 @@
 
 def mkaddr():
     w3 = Web3()
-    return w3.to_hex(w3.eth.account.create().key)
+    acct = w3.eth.account.create()
+    return (acct.address, w3.to_hex(acct.key))
 
 
 def main():
-    print(mkaddr())
+    address, key = mkaddr()
+    print(f'{address} {key}')
 
 
 if __name__ == '__main__':
diff --git a/tests/ulm/erc20/erc20_test.sh b/tests/ulm/erc20/erc20_test.sh
index 1357fe1d1..674a2a706 100755
--- a/tests/ulm/erc20/erc20_test.sh
+++ b/tests/ulm/erc20/erc20_test.sh
@@ -1,5 +1,7 @@
 #!/bin/bash
 
+set -e
+
 SCRIPT_DIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )
 ROOT_DIR="$SCRIPT_DIR/../../.."
 
@@ -12,38 +14,141 @@ if [ -z ${IN_POETRY_SHELL:+x} ]; then
   exec poetry -C pykwasm run bash "$SCRIPT_DIR/$(basename -- $0)"
 fi
 
-# generate some accounts
-a1=$(mkacct)
-echo "Account1: $a1"
 
-a2=$(mkacct)
-echo "Account2: $a2"
+RED='\033[0;31m'
+NC='\033[0m'
+GREEN="\033[0;32m"
+BLUE="\033[0;34m"
+WHITE="\033[0;00m"
+
+function assert_eq {
+  if [ ! "$1" == "$2" ]; then
+    >&2 echo -e "${RED}$3${NC}: Expected $1 to be equal to $2"
+    exit 1
+  fi
+}
+
+function to_hex {
+  printf "0x%x" $1
+}
+
+function erc20_deploy {
+  local key=$1
+  deploy build/erc20/erc20.bin http://localhost:8545 /dev/stdin <<< $key
+}
+
+function erc20_decimals {
+  local key=$1
+  local contract=$2
+  call http://localhost:8545 erc20 $contract /dev/stdin 0 decimals <<< $key
+}
+
+function erc20_totalSupply {
+  local key=$1
+  local contract=$2
+  call http://localhost:8545 erc20 $contract /dev/stdin 0 totalSupply <<< $key
+}
+
+function erc20_balanceOf {
+  local key=$1
+  local contract=$2
+  local account=$3
+  call http://localhost:8545 erc20 $contract /dev/stdin 0 balanceOf $account <<< $key
+}
+
+function erc20_mint {
+  local key=$1
+  local contract=$2
+  local account=$3
+  local amount=$4
+  call http://localhost:8545 erc20 $contract /dev/stdin 0 mint $account $amount <<< $key
+}
+
+function test_decimals {
+  echo "Decimals test"
+
+  # generate some accounts
+  account1=($(mkacct))
+  a1=${account1[0]}
+  k1=${account1[1]}
+  echo "Account 1. address: $a1; key: $k1"
+
+  # fund accounts
+  fund /dev/stdin <<< $k1
+
+  # deploy contract
+  contract=$(erc20_deploy $k1)
+  echo "Contract deployed. Contract address: $contract"
+
+  decimals=$(erc20_decimals $k1 $contract)
+  assert_eq "18" "$decimals" "Decimals"
+}
+
+function test_mint {
+  echo "Mint test"
+
+  # generate some accounts
+  account1=($(mkacct))
+  a1=${account1[0]}
+  k1=${account1[1]}
+  echo "Account 1. address: $a1; key: $k1"
+
+  account2=($(mkacct))
+  a2=${account2[0]}
+  k2=${account2[1]}
+  echo "Account 2. address: $a2; key: $k2"
+
+  account3=($(mkacct))
+  a3=${account3[0]}
+  k3=${account3[1]}
+  echo "Account 3. address: $a3; key: $k3"
+
+  # fund accounts
+  fund /dev/stdin <<< $k1
+  fund /dev/stdin <<< $k2
+  fund /dev/stdin <<< $k3
+
+  # deploy contract
+  contract=$(erc20_deploy $k1)
+  echo "Contract deployed. Contract address: $contract"
+
+  balance2=$(erc20_balanceOf $k1 $contract $a2)
+  assert_eq "0" "$balance2" "Balance of Account 2"
+
+  balance3=$(erc20_balanceOf $k1 $contract $a3)
+  assert_eq "0" "$balance3" "Balance of Account 3"
+
+  # check total supply
+  supply=$(erc20_totalSupply $k1 $contract)
+  assert_eq "0" "$supply" "Total Supply"
+
+  erc20_mint $k1 $contract $a2 $(to_hex 1000)
+
+  balance2=$(erc20_balanceOf $k1 $contract $a2)
+  assert_eq "1000" "$balance2" "Balance of Account 2"
+
+  balance3=$(erc20_balanceOf $k1 $contract $a3)
+  assert_eq "0" "$balance3" "Balance of Account 3"
 
-a3=$(mkacct)
-echo "Account3: $a3"
+  # check total supply
+  supply=$(erc20_totalSupply $k1 $contract)
+  assert_eq "1000" "$supply" "Total Supply"
 
+  erc20_mint $k1 $contract $a3 $(to_hex 2000)
 
-# fund accounts
-echo "Funding account 1"
-fund /dev/stdin <<< $a1
+  balance2=$(erc20_balanceOf $k1 $contract $a2)
+  assert_eq "1000" "$balance2" "Balance of Account 2"
 
-echo "Funding account 2"
-fund /dev/stdin <<< $a2
+  balance3=$(erc20_balanceOf $k1 $contract $a3)
+  assert_eq "2000" "$balance3" "Balance of Account 3"
 
-echo "Funding account 3"
-fund /dev/stdin <<< $a3
+  # check total supply
+  supply=$(erc20_totalSupply $k1 $contract)
+  assert_eq "3000" "$supply" "Total Supply"
+}
 
-# deploy contract
-echo "Deploying contract"
-contract=$(deploy build/erc20/erc20.bin http://localhost:8545 /dev/stdin <<< $a1)
-echo "Contract deployed. Contract address: $contract"
+test_decimals
 
-# check decimals
-echo "Calling decimals on Account 1"
-decimals=$(call http://localhost:8545 erc20 $contract /dev/stdin 0 decimals <<< $a1)
-echo "Called decimals on Account 1. Result: $decimals"
+test_mint
 
-# check total supply
-echo "Calling supply on Account 1"
-supply=$(call http://localhost:8545 erc20 $contract /dev/stdin 0 totalSupply <<< $a1)
-echo "Called supply on Account 1. Result: $supply"
+echo -e "${GREEN}All tests passed${NC}"