diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 7bee31fe..102702da 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -62,7 +62,7 @@ jobs:
         uses: shivammathur/setup-php@cf4cade2721270509d5b1c766ab3549210a39a2a # v2
         with:
           php-version: ${{ matrix.php }}
-          coverage: xdebug
+          coverage: pcov
           extensions: ctype, json, mbstring
           tools: composer
 
@@ -113,7 +113,11 @@ jobs:
         run: composer audit
 
       - name: Run test suite
-        run: composer run-tests-with-clover
+        run: |
+          for file in $(find tests -name "*Test.php"); do
+            echo "Running tests from $file"
+            php ./bin/phpunit --configuration=./ci/phpunit/config.xml "$file"
+          done
 
       - name: Upload coverage results to Coveralls
         if: matrix.calculate-code-coverage == true
diff --git a/ci/phpunit/run-split-tests.sh b/ci/phpunit/run-split-tests.sh
new file mode 100755
index 00000000..cd6cf1c2
--- /dev/null
+++ b/ci/phpunit/run-split-tests.sh
@@ -0,0 +1,75 @@
+#!/usr/bin/env bash
+set -e
+
+# Get the directory of this script
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PROJECT_ROOT="$(cd "${SCRIPT_DIR}/../.." && pwd)"
+
+# Default test directories to scan
+TEST_DIRS=(
+  "tests/MartinGeorgiev/Doctrine/DBAL/Types"
+  "tests/MartinGeorgiev/Doctrine/ORM/Query/AST/Functions"
+  "tests/MartinGeorgiev/Utils"
+)
+
+# Parse command line arguments
+COVERAGE_ARGS=""
+if [[ "$@" == *"--coverage-clover"* ]]; then
+  COVERAGE_ARGS="--coverage-clover=./var/logs/test-coverage/clover.xml"
+fi
+
+# Additional PHPUnit arguments
+PHPUNIT_ARGS="--testdox --display-deprecations --display-errors --display-incomplete"
+
+# Create a temporary directory for individual coverage reports if needed
+if [[ -n "$COVERAGE_ARGS" ]]; then
+  mkdir -p "${PROJECT_ROOT}/var/logs/test-coverage/split"
+fi
+
+# Function to run tests for a specific file
+run_test_for_file() {
+  local test_file=$1
+  local relative_path=${test_file#"$PROJECT_ROOT/"}
+  
+  echo "Running tests for: $relative_path"
+  
+  if [[ -n "$COVERAGE_ARGS" ]]; then
+    # Generate a unique name for the coverage file
+    local coverage_file="split/$(basename "$test_file" .php).xml"
+    php "${PROJECT_ROOT}/vendor/bin/phpunit" --configuration="${PROJECT_ROOT}/ci/phpunit/config.xml" $PHPUNIT_ARGS --coverage-clover="${PROJECT_ROOT}/var/logs/test-coverage/$coverage_file" "$test_file"
+  else
+    php "${PROJECT_ROOT}/vendor/bin/phpunit" --configuration="${PROJECT_ROOT}/ci/phpunit/config.xml" $PHPUNIT_ARGS "$test_file"
+  fi
+  
+  echo "Completed: $relative_path"
+  echo "----------------------------------------"
+}
+
+# Find and run tests for each file
+for dir in "${TEST_DIRS[@]}"; do
+  if [[ -d "${PROJECT_ROOT}/${dir}" ]]; then
+    echo "Scanning directory: ${dir}"
+    
+    # Find all test files in the directory
+    while IFS= read -r -d '' test_file; do
+      run_test_for_file "$test_file"
+    done < <(find "${PROJECT_ROOT}/${dir}" -name "*Test.php" -type f -print0)
+  else
+    echo "Warning: Directory ${dir} does not exist, skipping."
+  fi
+done
+
+# If we're generating coverage, we need to merge the reports
+if [[ -n "$COVERAGE_ARGS" ]]; then
+  echo "Merging coverage reports..."
+  # You would need a tool like phpcov to merge the reports
+  # For now, we'll just use the last generated report as the main one
+  
+  # Future enhancement: Install phpcov and use it to merge reports
+  # vendor/bin/phpcov merge --clover="${PROJECT_ROOT}/var/logs/test-coverage/clover.xml" "${PROJECT_ROOT}/var/logs/test-coverage/split"
+  
+  echo "Note: Coverage reports are generated individually per test file."
+  echo "To get a combined report, consider installing phpcov."
+fi
+
+echo "All tests completed!"
diff --git a/composer.json b/composer.json
index a32aea44..9854780a 100644
--- a/composer.json
+++ b/composer.json
@@ -71,7 +71,7 @@
             "phpstan analyse --configuration=./ci/phpstan/config.neon"
         ],
         "phpunit": [
-            "XDEBUG_MODE=coverage phpunit --configuration=./ci/phpunit/config.xml"
+            "phpunit --configuration=./ci/phpunit/config.xml --testdox --display-deprecations --display-errors --display-incomplete"
         ],
         "rector": [
             "rector --config=./ci/rector/config.php --ansi --no-progress-bar"
@@ -94,6 +94,12 @@
         ],
         "run-tests-with-clover": [
             "@phpunit --coverage-clover=./var/logs/test-coverage/clover.xml"
+        ],
+        "run-tests-split": [
+            "bash ./ci/phpunit/run-split-tests.sh"
+        ],
+        "run-tests-split-with-clover": [
+            "bash ./ci/phpunit/run-split-tests.sh --coverage-clover=./var/logs/test-coverage/clover.xml"
         ]
     },
 
diff --git a/tests/MartinGeorgiev/Doctrine/ORM/Query/AST/Functions/BaseVariadicFunctionTestCase.php b/tests/MartinGeorgiev/Doctrine/ORM/Query/AST/Functions/BaseVariadicFunctionTestCase.php
index d262b1ff..36b97f17 100644
--- a/tests/MartinGeorgiev/Doctrine/ORM/Query/AST/Functions/BaseVariadicFunctionTestCase.php
+++ b/tests/MartinGeorgiev/Doctrine/ORM/Query/AST/Functions/BaseVariadicFunctionTestCase.php
@@ -4,39 +4,9 @@
 
 namespace Tests\MartinGeorgiev\Doctrine\ORM\Query\AST\Functions;
 
-use Doctrine\ORM\Configuration;
-use Doctrine\ORM\EntityManager;
-use Doctrine\ORM\Query;
-use Doctrine\ORM\Query\Parser;
 use MartinGeorgiev\Doctrine\ORM\Query\AST\Functions\BaseVariadicFunction;
-use MartinGeorgiev\Doctrine\ORM\Query\AST\Functions\Exception\ParserException;
 
 abstract class BaseVariadicFunctionTestCase extends TestCase
 {
     abstract protected function createFixture(): BaseVariadicFunction;
-
-    /**
-     * @test
-     */
-    public function throws_an_exception_when_lexer_is_not_populated_with_a_lookahead_type(): void
-    {
-        $this->expectException(ParserException::class);
-
-        $em = $this->createMock(EntityManager::class);
-        $em->expects($this->any())
-            ->method('getConfiguration')
-            ->willReturn(new Configuration());
-
-        $query = new Query($em);
-        $query->setDQL('TRUE');
-
-        $parser = new Parser($query);
-        $parser->getLexer()->moveNext();
-
-        $baseVariadicFunction = $this->createFixture();
-
-        $reflectionMethod = new \ReflectionMethod($baseVariadicFunction::class, 'feedParserWithNodesForNodeMappingPattern');
-        $reflectionMethod->setAccessible(true);
-        $reflectionMethod->invoke($baseVariadicFunction, $parser, 'ArithmeticPrimary');
-    }
 }
diff --git a/tests/MartinGeorgiev/Doctrine/ORM/Query/AST/Functions/RegexpInstrTest.php b/tests/MartinGeorgiev/Doctrine/ORM/Query/AST/Functions/RegexpInstrTest.php
deleted file mode 100644
index 9961699b..00000000
--- a/tests/MartinGeorgiev/Doctrine/ORM/Query/AST/Functions/RegexpInstrTest.php
+++ /dev/null
@@ -1,69 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Tests\MartinGeorgiev\Doctrine\ORM\Query\AST\Functions;
-
-use Fixtures\MartinGeorgiev\Doctrine\Entity\ContainsTexts;
-use MartinGeorgiev\Doctrine\ORM\Query\AST\Functions\BaseVariadicFunction;
-use MartinGeorgiev\Doctrine\ORM\Query\AST\Functions\Exception\InvalidArgumentForVariadicFunctionException;
-use MartinGeorgiev\Doctrine\ORM\Query\AST\Functions\RegexpInstr;
-
-class RegexpInstrTest extends BaseVariadicFunctionTestCase
-{
-    protected function createFixture(): BaseVariadicFunction
-    {
-        return new RegexpInstr('REGEXP_INSTR');
-    }
-
-    protected function getStringFunctions(): array
-    {
-        return [
-            'REGEXP_INSTR' => RegexpInstr::class,
-        ];
-    }
-
-    protected function getExpectedSqlStatements(): array
-    {
-        return [
-            'finds position of pattern' => "SELECT regexp_instr(c0_.text1, 'c(.)(...)') AS sclr_0 FROM ContainsTexts c0_",
-            'finds position of digits' => "SELECT regexp_instr(c0_.text1, '\\d+') AS sclr_0 FROM ContainsTexts c0_",
-            'with start position' => "SELECT regexp_instr(c0_.text1, '\\d+', 1) AS sclr_0 FROM ContainsTexts c0_",
-            'with start and occurrence' => "SELECT regexp_instr(c0_.text1, '\\d+', 1, 2) AS sclr_0 FROM ContainsTexts c0_",
-            'with start, occurrence and return_option' => "SELECT regexp_instr(c0_.text1, '\\d+', 1, 2, 0) AS sclr_0 FROM ContainsTexts c0_",
-            'with flags' => "SELECT regexp_instr(c0_.text1, '\\d+', 1, 2, 0, 'i') AS sclr_0 FROM ContainsTexts c0_",
-            'with subexpr' => "SELECT regexp_instr(c0_.text1, '\\d+', 1, 2, 0, 'i', 2) AS sclr_0 FROM ContainsTexts c0_",
-        ];
-    }
-
-    protected function getDqlStatements(): array
-    {
-        return [
-            'finds position of pattern' => \sprintf("SELECT REGEXP_INSTR(e.text1, 'c(.)(...)') FROM %s e", ContainsTexts::class),
-            'finds position of digits' => \sprintf("SELECT REGEXP_INSTR(e.text1, '\\d+') FROM %s e", ContainsTexts::class),
-            'with start position' => \sprintf("SELECT REGEXP_INSTR(e.text1, '\\d+', 1) FROM %s e", ContainsTexts::class),
-            'with start and occurrence' => \sprintf("SELECT REGEXP_INSTR(e.text1, '\\d+', 1, 2) FROM %s e", ContainsTexts::class),
-            'with start, occurrence and return_option' => \sprintf("SELECT REGEXP_INSTR(e.text1, '\\d+', 1, 2, 0) FROM %s e", ContainsTexts::class),
-            'with flags' => \sprintf("SELECT REGEXP_INSTR(e.text1, '\\d+', 1, 2, 0, 'i') FROM %s e", ContainsTexts::class),
-            'with subexpr' => \sprintf("SELECT REGEXP_INSTR(e.text1, '\\d+', 1, 2, 0, 'i', 2) FROM %s e", ContainsTexts::class),
-        ];
-    }
-
-    public function test_too_few_arguments_throws_exception(): void
-    {
-        $this->expectException(InvalidArgumentForVariadicFunctionException::class);
-        $this->expectExceptionMessage('regexp_instr() requires at least 2 arguments');
-
-        $dql = \sprintf('SELECT REGEXP_INSTR(e.text1) FROM %s e', ContainsTexts::class);
-        $this->buildEntityManager()->createQuery($dql)->getSQL();
-    }
-
-    public function test_too_many_arguments_throws_exception(): void
-    {
-        $this->expectException(InvalidArgumentForVariadicFunctionException::class);
-        $this->expectExceptionMessage('regexp_instr() requires between 2 and 7 arguments');
-
-        $dql = \sprintf("SELECT REGEXP_INSTR(e.text1, 'c(.)(..)', 1, 1, 0, 'i', 2, 'extra_arg') FROM %s e", ContainsTexts::class);
-        $this->buildEntityManager()->createQuery($dql)->getSQL();
-    }
-}