diff --git a/.env.example b/.env.example
index 164a2c57..e69de29b 100644
--- a/.env.example
+++ b/.env.example
@@ -1,2 +0,0 @@
-PARALLEL_RUN=
-
diff --git a/bashunit b/bashunit
index ca02a7af..2269317e 100755
--- a/bashunit
+++ b/bashunit
@@ -5,6 +5,7 @@ readonly BASH_UNIT_ROOT_DIR="$(dirname "${BASH_SOURCE[0]}")"
 source "$BASH_UNIT_ROOT_DIR/src/default_env_config.sh"
 source "$BASH_UNIT_ROOT_DIR/src/env_configuration.sh"
 source "$BASH_UNIT_ROOT_DIR/src/check_os.sh"
+source "$BASH_UNIT_ROOT_DIR/src/state.sh"
 source "$BASH_UNIT_ROOT_DIR/src/colors.sh"
 source "$BASH_UNIT_ROOT_DIR/src/console_results.sh"
 source "$BASH_UNIT_ROOT_DIR/src/helpers.sh"
diff --git a/bin/pre-commit b/bin/pre-commit
index 1b68b3a0..49cef02f 100755
--- a/bin/pre-commit
+++ b/bin/pre-commit
@@ -4,7 +4,7 @@ echo "Running pre-commit checks..."
 make pre_commit/run
 EXIT_CODE=$?
 
-if [ ${EXIT_CODE} -ne 0 ]; then
+if [[ ${EXIT_CODE} -ne 0 ]]; then
     echo "Pre Commit checks failed. Please fix the above issues before committing"
     exit ${EXIT_CODE}
 else
diff --git a/src/assert.sh b/src/assert.sh
index 3f6fea1e..676464ae 100755
--- a/src/assert.sh
+++ b/src/assert.sh
@@ -6,12 +6,12 @@ function assertEquals() {
   local label="${3:-$(Helper::normalizeTestFunctionName "${FUNCNAME[1]}")}"
 
   if [[ "$expected" != "$actual" ]]; then
-    ((_ASSERTIONS_FAILED++))
-    Console::printFailedTest  "${label}" "${expected}" "but got" "${actual}"
+    State::addAssertionsFailed
+    Console::printFailedTest "${label}" "${expected}" "but got" "${actual}"
     return
   fi
 
-  ((_ASSERTIONS_PASSED++))
+  State::addAssertionsPassed
 }
 
 function assertEmpty() {
@@ -19,12 +19,12 @@ function assertEmpty() {
   local label="${3:-$(Helper::normalizeTestFunctionName "${FUNCNAME[1]}")}"
 
   if [[ "$expected" != "" ]]; then
-    ((_ASSERTIONS_FAILED++))
-    Console::printFailedTest  "${label}" "to be empty" "but got" "${expected}"
+    State::addAssertionsFailed
+    Console::printFailedTest "${label}" "to be empty" "but got" "${expected}"
     return
   fi
 
-  ((_ASSERTIONS_PASSED++))
+  State::addAssertionsPassed
 }
 
 function assertNotEmpty() {
@@ -32,12 +32,12 @@ function assertNotEmpty() {
   local label="${3:-$(Helper::normalizeTestFunctionName "${FUNCNAME[1]}")}"
 
   if [[ "$expected" == "" ]]; then
-    ((_ASSERTIONS_FAILED++))
-    Console::printFailedTest  "${label}" "to not be empty" "but got" "${expected}"
+    State::addAssertionsFailed
+    Console::printFailedTest "${label}" "to not be empty" "but got" "${expected}"
     return
   fi
 
-  ((_ASSERTIONS_PASSED++))
+  State::addAssertionsPassed
 }
 
 function assertNotEquals() {
@@ -46,12 +46,12 @@ function assertNotEquals() {
   local label="${3:-$(Helper::normalizeTestFunctionName "${FUNCNAME[1]}")}"
 
   if [[ "$expected" == "$actual" ]]; then
-    ((_ASSERTIONS_FAILED++))
-    Console::printFailedTest  "${label}" "${expected}" "but got" "${actual}"
+    State::addAssertionsFailed
+    Console::printFailedTest "${label}" "${expected}" "but got" "${actual}"
     return
   fi
 
-  ((_ASSERTIONS_PASSED++))
+  State::addAssertionsPassed
 }
 
 function assertContains() {
@@ -60,12 +60,12 @@ function assertContains() {
   local label="${3:-$(Helper::normalizeTestFunctionName "${FUNCNAME[1]}")}"
 
   if ! [[ $actual == *"$expected"* ]]; then
-    ((_ASSERTIONS_FAILED++))
-    Console::printFailedTest  "${label}" "${actual}" "to contain" "${expected}"
+    State::addAssertionsFailed
+    Console::printFailedTest "${label}" "${actual}" "to contain" "${expected}"
     return
   fi
 
-  ((_ASSERTIONS_PASSED++))
+  State::addAssertionsPassed
 }
 
 function assertNotContains() {
@@ -74,12 +74,12 @@ function assertNotContains() {
   local label="${3:-$(Helper::normalizeTestFunctionName "${FUNCNAME[1]}")}"
 
   if [[ $actual == *"$expected"* ]]; then
-    ((_ASSERTIONS_FAILED++))
-    Console::printFailedTest  "${label}" "${actual}" "to not contain" "${expected}"
+    State::addAssertionsFailed
+    Console::printFailedTest "${label}" "${actual}" "to not contain" "${expected}"
     return
   fi
 
-  ((_ASSERTIONS_PASSED++))
+  State::addAssertionsPassed
 }
 
 function assertMatches() {
@@ -88,12 +88,12 @@ function assertMatches() {
   local label="${3:-$(Helper::normalizeTestFunctionName "${FUNCNAME[1]}")}"
 
   if ! [[ $actual =~ $expected ]]; then
-    ((_ASSERTIONS_FAILED++))
-    Console::printFailedTest  "${label}" "${actual}" "to match" "${expected}"
+    State::addAssertionsFailed
+    Console::printFailedTest "${label}" "${actual}" "to match" "${expected}"
     return
   fi
 
-  ((_ASSERTIONS_PASSED++))
+  State::addAssertionsPassed
 }
 
 function assertNotMatches() {
@@ -102,12 +102,12 @@ function assertNotMatches() {
   local label="${3:-$(Helper::normalizeTestFunctionName "${FUNCNAME[1]}")}"
 
   if [[ $actual =~ $expected ]]; then
-    ((_ASSERTIONS_FAILED++))
-    Console::printFailedTest  "${label}" "${actual}" "to not match" "${expected}"
+    State::addAssertionsFailed
+    Console::printFailedTest "${label}" "${actual}" "to not match" "${expected}"
     return
   fi
 
-  ((_ASSERTIONS_PASSED++))
+  State::addAssertionsPassed
 }
 
 function assertExitCode() {
@@ -115,13 +115,13 @@ function assertExitCode() {
   local expected_exit_code="$1"
   local label="${3:-$(Helper::normalizeTestFunctionName "${FUNCNAME[1]}")}"
 
-  if [ $actual_exit_code -ne "$expected_exit_code" ]; then
-    ((_ASSERTIONS_FAILED++))
-    Console::printFailedTest  "${label}" "${actual_exit_code}" "to be" "${expected_exit_code}"
+  if [[ $actual_exit_code -ne "$expected_exit_code" ]]; then
+    State::addAssertionsFailed
+    Console::printFailedTest "${label}" "${actual_exit_code}" "to be" "${expected_exit_code}"
     return
   fi
 
-  ((_ASSERTIONS_PASSED++))
+  State::addAssertionsPassed
 }
 
 function assertSuccessfulCode() {
@@ -129,13 +129,13 @@ function assertSuccessfulCode() {
   local expected_exit_code=0
   local label="${3:-$(Helper::normalizeTestFunctionName "${FUNCNAME[1]}")}"
 
-  if [[ $actual_exit_code != "$expected_exit_code" ]]; then
-    ((_ASSERTIONS_FAILED++))
-    Console::printFailedTest  "${label}" "${actual_exit_code}" "to be exactly" "${expected_exit_code}"
+  if [[ $actual_exit_code -ne "$expected_exit_code" ]]; then
+    State::addAssertionsFailed
+    Console::printFailedTest "${label}" "${actual_exit_code}" "to be exactly" "${expected_exit_code}"
     return
   fi
 
-  ((_ASSERTIONS_PASSED++))
+  State::addAssertionsPassed
 }
 
 function assertGeneralError() {
@@ -143,13 +143,13 @@ function assertGeneralError() {
   local expected_exit_code=1
   local label="${3:-$(Helper::normalizeTestFunctionName "${FUNCNAME[1]}")}"
 
-  if [ $actual_exit_code -ne "$expected_exit_code" ]; then
-    ((_ASSERTIONS_FAILED++))
-    Console::printFailedTest  "${label}" "${actual_exit_code}" "to be exactly" "${expected_exit_code}"
+  if [[ $actual_exit_code -ne "$expected_exit_code" ]]; then
+    State::addAssertionsFailed
+    Console::printFailedTest "${label}" "${actual_exit_code}" "to be exactly" "${expected_exit_code}"
     return
   fi
 
-  ((_ASSERTIONS_PASSED++))
+  State::addAssertionsPassed
 }
 
 
@@ -158,13 +158,13 @@ function assertCommandNotFound() {
   local expected_exit_code=127
   local label="${3:-$(Helper::normalizeTestFunctionName "${FUNCNAME[1]}")}"
 
-  if [ $actual_exit_code -ne "$expected_exit_code" ]; then
-    ((_ASSERTIONS_FAILED++))
-    Console::printFailedTest  "${label}" "${actual_exit_code}" "to be exactly" "${expected_exit_code}"
+  if [[ $actual_exit_code -ne "$expected_exit_code" ]]; then
+    State::addAssertionsFailed
+    Console::printFailedTest "${label}" "${actual_exit_code}" "to be exactly" "${expected_exit_code}"
     return
   fi
 
-  ((_ASSERTIONS_PASSED++))
+  State::addAssertionsPassed
 }
 
 function assertArrayContains() {
@@ -174,12 +174,12 @@ function assertArrayContains() {
   local actual=("$@")
 
   if ! [[ "${actual[*]}" == *"$expected"* ]]; then
-    ((_ASSERTIONS_FAILED++))
-    Console::printFailedTest  "${label}" "${actual[*]}" "to contain" "${expected}"
+    State::addAssertionsFailed
+    Console::printFailedTest "${label}" "${actual[*]}" "to contain" "${expected}"
     return
   fi
 
-  ((_ASSERTIONS_PASSED++))
+  State::addAssertionsPassed
 }
 
 function assertArrayNotContains() {
@@ -189,10 +189,10 @@ function assertArrayNotContains() {
   local actual=("$@")
 
   if [[ "${actual[*]}" == *"$expected"* ]]; then
-    ((_ASSERTIONS_FAILED++))
-    Console::printFailedTest  "${label}" "${actual[*]}" "to not contain" "${expected}"
+    State::addAssertionsFailed
+    Console::printFailedTest "${label}" "${actual[*]}" "to not contain" "${expected}"
     return
   fi
 
-  ((_ASSERTIONS_PASSED++))
+  State::addAssertionsPassed
 }
diff --git a/src/check_os.sh b/src/check_os.sh
index ed540939..b7025493 100644
--- a/src/check_os.sh
+++ b/src/check_os.sh
@@ -3,9 +3,9 @@
 # shellcheck disable=SC2034
 _OS="Unknown"
 
-if [ "$(uname)" == "Linux" ]; then
+if [[ "$(uname)" == "Linux" ]]; then
   _OS="Linux"
-elif [ "$(uname)" == "Darwin" ]; then
+elif [[ "$(uname)" == "Darwin" ]]; then
   _OS="OSX"
 elif [[ $(uname) == *"MINGW"* ]]; then
   _OS="Windows"
diff --git a/src/console_results.sh b/src/console_results.sh
index 4a4a8f25..ff3aed4f 100644
--- a/src/console_results.sh
+++ b/src/console_results.sh
@@ -1,10 +1,6 @@
 #!/bin/bash
 
 _START_TIME=$(date +%s%N);
-_TESTS_PASSED=0
-_TESTS_FAILED=0
-_ASSERTIONS_PASSED=0
-_ASSERTIONS_FAILED=0
 
 function Console::renderResult() {
   local tests_passed=$1
@@ -46,7 +42,7 @@ function Console::renderResult() {
 }
 
 function Console::printExecutionTime() {
-  if [ "$_OS" != "OSX" ]; then
+  if [[ "$_OS" != "OSX" ]]; then
     _EXECUTION_TIME=$((($(date +%s%N) - "$_START_TIME") / 1000000))
     printf "${_COLOR_BOLD}%s${_COLOR_DEFAULT}\n" "Time taken: ${_EXECUTION_TIME} ms"
   fi
@@ -70,6 +66,3 @@ ${_COLOR_FAILED}✗ Failed${_COLOR_DEFAULT}: %s
     "${test_name}" "${expected}" "${failure_condition_message}" "${actual}"
 
 }
-
-# Set a trap to call renderResult when the script exits
-trap 'Console::renderResult $_TESTS_PASSED $_TESTS_FAILED $_ASSERTIONS_PASSED $_ASSERTIONS_FAILED' EXIT
diff --git a/src/default_env_config.sh b/src/default_env_config.sh
index 7ecbc970..5893beab 100644
--- a/src/default_env_config.sh
+++ b/src/default_env_config.sh
@@ -1,2 +1,4 @@
 #!/bin/bash
-export _DEFAULT_PARALLEL_RUN=false
+
+# shellcheck disable=SC2034
+_DEFAULT_PARALLEL_RUN=false
diff --git a/src/env_configuration.sh b/src/env_configuration.sh
index e304c4cc..8dfc63d9 100644
--- a/src/env_configuration.sh
+++ b/src/env_configuration.sh
@@ -5,6 +5,6 @@ set -o allexport
 [[ -f ".env" ]] && source .env set
 set +o allexport
 
-if [ -z "$PARALLEL_RUN" ]; then
+if [[ -z "$PARALLEL_RUN" ]]; then
   PARALLEL_RUN=$_DEFAULT_PARALLEL_RUN
 fi
diff --git a/src/runner.sh b/src/runner.sh
index 51a0794b..baf031cd 100755
--- a/src/runner.sh
+++ b/src/runner.sh
@@ -11,14 +11,11 @@ function Runner::callTestFunctions() {
   # shellcheck disable=SC2207
   functions_to_run=($(Helper::getFunctionsToRun "$prefix" "$filter" "$function_names"))
 
-  if [ "${#functions_to_run[@]}" -gt 0 ]; then
+  if [[ "${#functions_to_run[@]}" -gt 0 ]]; then
     echo "Running $script"
     for function_name in "${functions_to_run[@]}"; do
-      if [ "$PARALLEL_RUN" == true ] ; then
-        Runner::runTest "$function_name" &
-      else
-        Runner::runTest "$function_name"
-      fi
+      Runner::runTest "$function_name"
+
       unset "$function_name"
     done
   fi
@@ -26,19 +23,43 @@ function Runner::callTestFunctions() {
 
 function Runner::runTest() {
   local function_name="$1"
-  local current_assertions_failed="$_ASSERTIONS_FAILED"
+  local current_assertions_failed
+  current_assertions_failed="$(State::getAssertionsFailed)"
 
   Runner::runSetUp
   "$function_name"
   Runner::runTearDown
 
-  if [ "$current_assertions_failed" == "$_ASSERTIONS_FAILED" ]; then
-    ((_TESTS_PASSED++))
-    local label="${3:-$(Helper::normalizeTestFunctionName "$function_name")}"
-    Console::printSuccessfulTest "${label}"
-  else
-    ((_TESTS_FAILED++))
+  if [[ "$current_assertions_failed" != "$(State::getAssertionsFailed)" ]]; then
+    State::addTestsFailed
+    return
   fi
+
+  local label="${3:-$(Helper::normalizeTestFunctionName "$function_name")}"
+  Console::printSuccessfulTest "${label}"
+  State::addTestsPassed
+}
+
+function Runner::loadTestFiles() {
+  if [[ ${#_FILES[@]} -eq 0 ]]; then
+    echo "Error: At least one file path is required."
+    echo "Usage: $0 <test_file.sh>"
+    exit 1
+  fi
+
+  for test_file in "${_FILES[@]}"; do
+    if [[ ! -f $test_file ]]; then
+      continue
+    fi
+
+    #shellcheck source=/dev/null
+    source "$test_file"
+
+    Runner::runSetUpBeforeScript
+    Runner::callTestFunctions "$test_file" "$_FILTER"
+    Runner::runTearDownAfterScript
+    Runner::cleanSetUpAndTearDownAfterScript
+  done
 }
 
 function Runner::runSetUp() {
@@ -74,7 +95,7 @@ function Runner::cleanSetUpAndTearDownAfterScript() {
 _FILES=()
 _FILTER=""
 
-while [ $# -gt 0 ]; do
+while [[ $# -gt 0 ]]; do
   argument="$1"
   case $argument in
     --filter)
@@ -89,32 +110,10 @@ while [ $# -gt 0 ]; do
   esac
 done
 
-
-
-function Runner::loadTestFiles() {
-  if [ ${#_FILES[@]} -eq 0 ]; then
-    echo "Error: At least one file path is required."
-    echo "Usage: $0 <test_file.sh>"
-    exit 1
-  fi
-
-  for test_file in "${_FILES[@]}"; do
-    if [[ ! -f $test_file ]];
-    then
-      continue
-    fi
-    # shellcheck disable=SC1090
-    source "$test_file"
-    Runner::runSetUpBeforeScript
-    Runner::callTestFunctions "$test_file" "$_FILTER"
-    if [ "$PARALLEL_RUN" = true ] ; then
-      wait
-    fi
-    Runner::runTearDownAfterScript
-
-    Runner::cleanSetUpAndTearDownAfterScript
-  done
-}
-
 Runner::loadTestFiles
 
+trap 'Console::renderResult '\
+'"$(State::getTestsPassed)" '\
+'"$(State::getTestsFailed)" '\
+'"$(State::getAssertionsPassed)" '\
+'"$(State::getAssertionsFailed)"' EXIT
diff --git a/src/state.sh b/src/state.sh
new file mode 100644
index 00000000..f45d0612
--- /dev/null
+++ b/src/state.sh
@@ -0,0 +1,38 @@
+#!/bin/bash
+
+_TESTS_PASSED=0
+_TESTS_FAILED=0
+_ASSERTIONS_PASSED=0
+_ASSERTIONS_FAILED=0
+
+function State::getTestsPassed() {
+  echo "$_TESTS_PASSED"
+}
+
+function State::addTestsPassed() {
+  ((_TESTS_PASSED++))
+}
+
+function State::getTestsFailed() {
+  echo "$_TESTS_FAILED"
+}
+
+function State::addTestsFailed() {
+  ((_TESTS_FAILED++))
+}
+
+function State::getAssertionsPassed() {
+  echo "$_ASSERTIONS_PASSED"
+}
+
+function State::addAssertionsPassed() {
+  ((_ASSERTIONS_PASSED++))
+}
+
+function State::getAssertionsFailed() {
+  echo "$_ASSERTIONS_FAILED"
+}
+
+function State::addAssertionsFailed() {
+  ((_ASSERTIONS_FAILED++))
+}
diff --git a/tests/acceptance/bashunit_test.sh b/tests/acceptance/bashunit_test.sh
index 29f84063..b149a3ad 100644
--- a/tests/acceptance/bashunit_test.sh
+++ b/tests/acceptance/bashunit_test.sh
@@ -40,7 +40,3 @@ function test_fail() { assertEquals \"1\" \"0\" ; }" > $test_file
 
   rm $test_file
 }
-
-function test_when_running_bashunit_without_error_then_exit_code_should_be_success() {
-  assertSuccessfulCode "$(./bashunit)"
-}