diff --git a/composer.json b/composer.json
index 12fa649812c..666260b66da 100644
--- a/composer.json
+++ b/composer.json
@@ -50,6 +50,7 @@
         "amphp/phpunit-util": "^3",
         "bamarni/composer-bin-plugin": "^1.4",
         "brianium/paratest": "^6.9",
+        "dg/bypass-finals": "^1.5",
         "mockery/mockery": "^1.5",
         "nunomaduro/mock-final-classes": "^1.1",
         "php-parallel-lint/php-parallel-lint": "^1.2",
diff --git a/examples/TemplateChecker.php b/examples/TemplateChecker.php
index 7fec45544dc..4e911dd268d 100644
--- a/examples/TemplateChecker.php
+++ b/examples/TemplateChecker.php
@@ -30,7 +30,7 @@
 use function strtolower;
 use function trim;
 
-class TemplateAnalyzer extends Psalm\Internal\Analyzer\FileAnalyzer
+final class TemplateAnalyzer extends Psalm\Internal\Analyzer\FileAnalyzer
 {
     final public const VIEW_CLASS = 'Your\\View\\Class';
 
@@ -148,7 +148,7 @@ private function checkMethod(MethodIdentifier $method_id, PhpParser\Node $stmt,
     /**
      * @param  array<PhpParser\Node\Stmt> $stmts
      */
-    protected function checkWithViewClass(Context $context, array $stmts): void
+    private function checkWithViewClass(Context $context, array $stmts): void
     {
         $pseudo_method_stmts = [];
 
diff --git a/examples/TemplateScanner.php b/examples/TemplateScanner.php
index 681bf61bdc7..254b06dc338 100644
--- a/examples/TemplateScanner.php
+++ b/examples/TemplateScanner.php
@@ -14,7 +14,7 @@
 use function preg_match;
 use function trim;
 
-class TemplateScanner extends Psalm\Internal\Scanner\FileScanner
+final class TemplateScanner extends Psalm\Internal\Scanner\FileScanner
 {
     final public const VIEW_CLASS = 'Your\\View\\Class';
 
diff --git a/examples/plugins/ClassUnqualifier.php b/examples/plugins/ClassUnqualifier.php
index 97cecee648c..d2b05332329 100644
--- a/examples/plugins/ClassUnqualifier.php
+++ b/examples/plugins/ClassUnqualifier.php
@@ -12,7 +12,7 @@
 use function strpos;
 use function strtolower;
 
-class ClassUnqualifier implements AfterClassLikeExistenceCheckInterface
+final class ClassUnqualifier implements AfterClassLikeExistenceCheckInterface
 {
     public static function afterClassLikeExistenceCheck(
         AfterClassLikeExistenceCheckEvent $event
diff --git a/examples/plugins/FunctionCasingChecker.php b/examples/plugins/FunctionCasingChecker.php
index f4d8c6a2e3e..56ec8983203 100644
--- a/examples/plugins/FunctionCasingChecker.php
+++ b/examples/plugins/FunctionCasingChecker.php
@@ -21,7 +21,7 @@
 /**
  * Checks that functions and methods are correctly-cased
  */
-class FunctionCasingChecker implements AfterFunctionCallAnalysisInterface, AfterMethodCallAnalysisInterface
+final class FunctionCasingChecker implements AfterFunctionCallAnalysisInterface, AfterMethodCallAnalysisInterface
 {
     public static function afterMethodCallAnalysis(AfterMethodCallAnalysisEvent $event): void
     {
@@ -99,6 +99,6 @@ public static function afterFunctionCallAnalysis(AfterFunctionCallAnalysisEvent
     }
 }
 
-class IncorrectFunctionCasing extends PluginIssue
+final class IncorrectFunctionCasing extends PluginIssue
 {
 }
diff --git a/examples/plugins/InternalChecker.php b/examples/plugins/InternalChecker.php
index a5c6306bab0..0b2ea575187 100644
--- a/examples/plugins/InternalChecker.php
+++ b/examples/plugins/InternalChecker.php
@@ -12,7 +12,7 @@
 
 use function strpos;
 
-class InternalChecker implements AfterClassLikeAnalysisInterface
+final class InternalChecker implements AfterClassLikeAnalysisInterface
 {
     /** @return null|false */
     public static function afterStatementAnalysis(AfterClassLikeAnalysisEvent $event): ?bool
diff --git a/examples/plugins/PreventFloatAssignmentChecker.php b/examples/plugins/PreventFloatAssignmentChecker.php
index 18b5630efbc..5bc7b0765bb 100644
--- a/examples/plugins/PreventFloatAssignmentChecker.php
+++ b/examples/plugins/PreventFloatAssignmentChecker.php
@@ -12,7 +12,7 @@
 /**
  * Prevents any assignment to a float value
  */
-class PreventFloatAssignmentChecker implements AfterExpressionAnalysisInterface
+final class PreventFloatAssignmentChecker implements AfterExpressionAnalysisInterface
 {
     /**
      * Called after an expression has been checked
@@ -40,6 +40,6 @@ public static function afterExpressionAnalysis(AfterExpressionAnalysisEvent $eve
     }
 }
 
-class NoFloatAssignment extends PluginIssue
+final class NoFloatAssignment extends PluginIssue
 {
 }
diff --git a/examples/plugins/SafeArrayKeyChecker.php b/examples/plugins/SafeArrayKeyChecker.php
index 5ea69772535..0360ed79155 100644
--- a/examples/plugins/SafeArrayKeyChecker.php
+++ b/examples/plugins/SafeArrayKeyChecker.php
@@ -7,7 +7,7 @@
 use Psalm\Plugin\EventHandler\Event\AddRemoveTaintsEvent;
 use Psalm\Plugin\EventHandler\RemoveTaintsInterface;
 
-class SafeArrayKeyChecker implements RemoveTaintsInterface
+final class SafeArrayKeyChecker implements RemoveTaintsInterface
 {
     /**
      * Called to see what taints should be removed
diff --git a/examples/plugins/StringChecker.php b/examples/plugins/StringChecker.php
index 070bcde5ac4..1ce7a814086 100644
--- a/examples/plugins/StringChecker.php
+++ b/examples/plugins/StringChecker.php
@@ -16,7 +16,7 @@
 use function strpos;
 use function strtolower;
 
-class StringChecker implements AfterExpressionAnalysisInterface
+final class StringChecker implements AfterExpressionAnalysisInterface
 {
     /**
      * Called after an expression has been checked
diff --git a/examples/plugins/composer-based/echo-checker/EchoChecker.php b/examples/plugins/composer-based/echo-checker/EchoChecker.php
index 668206c26e3..642e0a53e9c 100644
--- a/examples/plugins/composer-based/echo-checker/EchoChecker.php
+++ b/examples/plugins/composer-based/echo-checker/EchoChecker.php
@@ -11,7 +11,7 @@
 use Psalm\Type\Atomic\TLiteralString;
 use Psalm\Type\Atomic\TString;
 
-class EchoChecker implements AfterStatementAnalysisInterface
+final class EchoChecker implements AfterStatementAnalysisInterface
 {
     /**
      * Called after a statement has been checked
diff --git a/examples/plugins/composer-based/echo-checker/PluginEntryPoint.php b/examples/plugins/composer-based/echo-checker/PluginEntryPoint.php
index 4d6102281e4..e83927e0d04 100644
--- a/examples/plugins/composer-based/echo-checker/PluginEntryPoint.php
+++ b/examples/plugins/composer-based/echo-checker/PluginEntryPoint.php
@@ -6,7 +6,7 @@
 use Psalm\Plugin\RegistrationInterface;
 use SimpleXMLElement;
 
-class PluginEntryPoint implements PluginEntryPointInterface
+final class PluginEntryPoint implements PluginEntryPointInterface
 {
     public function __invoke(RegistrationInterface $registration, ?SimpleXMLElement $config = null): void
     {
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 748be83439b..4f2c25cff79 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:noNamespaceSchemaLocation="./vendor/phpunit/phpunit/phpunit.xsd"
-         bootstrap="vendor/autoload.php"
+         bootstrap="tests/autoload.php"
          backupGlobals="false"
          beStrictAboutCoversAnnotation="true"
          beStrictAboutOutputDuringTests="true"
diff --git a/src/Psalm/Config.php b/src/Psalm/Config.php
index b9a6d4d958c..4d1361c7bee 100644
--- a/src/Psalm/Config.php
+++ b/src/Psalm/Config.php
@@ -128,7 +128,7 @@
  * @psalm-suppress PropertyNotSetInConstructor
  * @psalm-consistent-constructor
  */
-class Config
+final class Config
 {
     private const DEFAULT_FILE_NAME = 'psalm.xml';
     final public const CONFIG_NAMESPACE = 'https://getpsalm.org/schema/config';
@@ -173,7 +173,7 @@ class Config
      *
      * @var array<int, lowercase-string>
      */
-    protected array $universal_object_crates;
+    private array $universal_object_crates;
 
     /**
      * @var static|null
@@ -223,7 +223,7 @@ class Config
 
     protected ?ProjectFileFilter $project_files = null;
 
-    protected ?ProjectFileFilter $extra_files = null;
+    private ?ProjectFileFilter $extra_files = null;
 
     /**
      * The base directory of this config file
@@ -427,7 +427,7 @@ class Config
 
     private ?IncludeCollector $include_collector = null;
 
-    protected ?TaintAnalysisFileFilter $taint_analysis_ignored_files = null;
+    private ?TaintAnalysisFileFilter $taint_analysis_ignored_files = null;
 
     /**
      * @var bool whether to emit a backtrace of emitted issues to stderr
@@ -567,7 +567,7 @@ class Config
     public array $config_warnings = [];
 
     /** @internal */
-    protected function __construct()
+    private function __construct()
     {
         self::$instance = $this;
         $this->eventDispatcher = new EventDispatcher();
diff --git a/src/Psalm/Exception/DocblockParseException.php b/src/Psalm/Exception/DocblockParseException.php
index 433f6632d2e..306c7eeb8dc 100644
--- a/src/Psalm/Exception/DocblockParseException.php
+++ b/src/Psalm/Exception/DocblockParseException.php
@@ -6,6 +6,6 @@
 
 use Exception;
 
-class DocblockParseException extends Exception
+final class DocblockParseException extends Exception
 {
 }
diff --git a/src/Psalm/Internal/Analyzer/FileAnalyzer.php b/src/Psalm/Internal/Analyzer/FileAnalyzer.php
index 62aeac08f2f..85b2b57592f 100644
--- a/src/Psalm/Internal/Analyzer/FileAnalyzer.php
+++ b/src/Psalm/Internal/Analyzer/FileAnalyzer.php
@@ -41,13 +41,13 @@
  * @internal
  * @psalm-consistent-constructor
  */
-class FileAnalyzer extends SourceAnalyzer
+final class FileAnalyzer extends SourceAnalyzer
 {
     use CanAlias;
 
-    protected ?string $root_file_path = null;
+    private ?string $root_file_path = null;
 
-    protected ?string $root_file_name = null;
+    private ?string $root_file_name = null;
 
     /**
      * @var array<string, bool>
diff --git a/src/Psalm/Internal/Analyzer/NamespaceAnalyzer.php b/src/Psalm/Internal/Analyzer/NamespaceAnalyzer.php
index a6bac10d51a..7a9a50bdc25 100644
--- a/src/Psalm/Internal/Analyzer/NamespaceAnalyzer.php
+++ b/src/Psalm/Internal/Analyzer/NamespaceAnalyzer.php
@@ -35,7 +35,7 @@ final class NamespaceAnalyzer extends SourceAnalyzer
      *
      * @var array<string, array<string, Union>>
      */
-    protected static array $public_namespace_constants = [];
+    private static array $public_namespace_constants = [];
 
     public function __construct(
         private readonly Namespace_ $namespace, /**
diff --git a/src/Psalm/Internal/Analyzer/ProjectAnalyzer.php b/src/Psalm/Internal/Analyzer/ProjectAnalyzer.php
index c4ff79c024f..ef9e130aad7 100644
--- a/src/Psalm/Internal/Analyzer/ProjectAnalyzer.php
+++ b/src/Psalm/Internal/Analyzer/ProjectAnalyzer.php
@@ -957,7 +957,7 @@ public function addExtraFile(string $file_path): void
     /**
      * @return list<string>
      */
-    protected function getDiffFiles(): array
+    private function getDiffFiles(): array
     {
         if (!$this->parser_cache_provider || !$this->project_cache_provider) {
             throw new UnexpectedValueException('Parser cache provider cannot be null here');
diff --git a/src/Psalm/Internal/Analyzer/Statements/Expression/AssertionFinder.php b/src/Psalm/Internal/Analyzer/Statements/Expression/AssertionFinder.php
index 560305843d4..79e102de0e5 100644
--- a/src/Psalm/Internal/Analyzer/Statements/Expression/AssertionFinder.php
+++ b/src/Psalm/Internal/Analyzer/Statements/Expression/AssertionFinder.php
@@ -928,7 +928,7 @@ private static function processIrreconcilableFunctionCall(
      * @param  PhpParser\Node\Expr\FuncCall|PhpParser\Node\Expr\MethodCall|PhpParser\Node\Expr\StaticCall $expr
      * @return list<non-empty-array<string, non-empty-list<non-empty-list<Assertion>>>>
      */
-    protected static function processCustomAssertion(
+    private static function processCustomAssertion(
         PhpParser\Node\Expr $expr,
         ?string $this_class_name,
         FileSource $source,
@@ -1230,7 +1230,7 @@ protected static function processCustomAssertion(
     /**
      * @return list<Assertion>
      */
-    protected static function getInstanceOfAssertions(
+    private static function getInstanceOfAssertions(
         PhpParser\Node\Expr\Instanceof_ $stmt,
         ?string $this_class_name,
         FileSource $source,
@@ -1295,7 +1295,7 @@ protected static function getInstanceOfAssertions(
     /**
      * @param Identical|Equal|NotIdentical|NotEqual $conditional
      */
-    protected static function hasNullVariable(
+    private static function hasNullVariable(
         PhpParser\Node\Expr\BinaryOp $conditional,
         FileSource $source,
     ): ?int {
@@ -1366,7 +1366,7 @@ public static function hasTrueVariable(
     /**
      * @param Identical|Equal|NotIdentical|NotEqual $conditional
      */
-    protected static function hasEmptyArrayVariable(
+    private static function hasEmptyArrayVariable(
         PhpParser\Node\Expr\BinaryOp $conditional,
     ): ?int {
         if ($conditional->right instanceof PhpParser\Node\Expr\Array_
@@ -1387,7 +1387,7 @@ protected static function hasEmptyArrayVariable(
     /**
      * @param Identical|Equal|NotIdentical|NotEqual $conditional
      */
-    protected static function hasGetTypeCheck(
+    private static function hasGetTypeCheck(
         PhpParser\Node\Expr\BinaryOp $conditional,
     ): false|int {
         if ($conditional->right instanceof PhpParser\Node\Expr\FuncCall
@@ -1414,7 +1414,7 @@ protected static function hasGetTypeCheck(
     /**
      * @param Identical|Equal|NotIdentical|NotEqual $conditional
      */
-    protected static function hasGetDebugTypeCheck(
+    private static function hasGetDebugTypeCheck(
         PhpParser\Node\Expr\BinaryOp $conditional,
     ): false|int {
         if ($conditional->right instanceof PhpParser\Node\Expr\FuncCall
@@ -1443,7 +1443,7 @@ protected static function hasGetDebugTypeCheck(
     /**
      * @param Identical|Equal|NotIdentical|NotEqual $conditional
      */
-    protected static function hasGetClassCheck(
+    private static function hasGetClassCheck(
         PhpParser\Node\Expr\BinaryOp $conditional,
         FileSource $source,
     ): false|int {
@@ -1535,7 +1535,7 @@ protected static function hasGetClassCheck(
     /**
      * @param Greater|GreaterOrEqual|Smaller|SmallerOrEqual $conditional
      */
-    protected static function hasNonEmptyCountEqualityCheck(
+    private static function hasNonEmptyCountEqualityCheck(
         PhpParser\Node\Expr\BinaryOp $conditional,
         ?int &$min_count,
     ): false|int {
@@ -1576,7 +1576,7 @@ protected static function hasNonEmptyCountEqualityCheck(
     /**
      * @param Greater|GreaterOrEqual|Smaller|SmallerOrEqual $conditional
      */
-    protected static function hasLessThanCountEqualityCheck(
+    private static function hasLessThanCountEqualityCheck(
         PhpParser\Node\Expr\BinaryOp $conditional,
         ?int &$max_count,
     ): false|int {
@@ -1624,7 +1624,7 @@ protected static function hasLessThanCountEqualityCheck(
     /**
      * @param Equal|Identical|NotEqual|NotIdentical $conditional
      */
-    protected static function hasCountEqualityCheck(
+    private static function hasCountEqualityCheck(
         PhpParser\Node\Expr\BinaryOp $conditional,
         ?int &$count,
     ): false|int {
@@ -1656,7 +1656,7 @@ protected static function hasCountEqualityCheck(
     /**
      * @param PhpParser\Node\Expr\BinaryOp\Greater|PhpParser\Node\Expr\BinaryOp\GreaterOrEqual $conditional
      */
-    protected static function hasSuperiorNumberCheck(
+    private static function hasSuperiorNumberCheck(
         FileSource $source,
         PhpParser\Node\Expr\BinaryOp $conditional,
         ?int &$literal_value_comparison,
@@ -1715,7 +1715,7 @@ protected static function hasSuperiorNumberCheck(
     /**
      * @param PhpParser\Node\Expr\BinaryOp\Smaller|PhpParser\Node\Expr\BinaryOp\SmallerOrEqual $conditional
      */
-    protected static function hasInferiorNumberCheck(
+    private static function hasInferiorNumberCheck(
         FileSource $source,
         PhpParser\Node\Expr\BinaryOp $conditional,
         ?int &$literal_value_comparison,
@@ -1774,7 +1774,7 @@ protected static function hasInferiorNumberCheck(
     /**
      * @param PhpParser\Node\Expr\BinaryOp\Greater|PhpParser\Node\Expr\BinaryOp\GreaterOrEqual $conditional
      */
-    protected static function hasReconcilableNonEmptyCountEqualityCheck(
+    private static function hasReconcilableNonEmptyCountEqualityCheck(
         PhpParser\Node\Expr\BinaryOp $conditional,
     ): false|int {
         $left_count = $conditional->left instanceof PhpParser\Node\Expr\FuncCall
@@ -1795,7 +1795,7 @@ protected static function hasReconcilableNonEmptyCountEqualityCheck(
     /**
      * @param Identical|Equal|NotIdentical|NotEqual $conditional
      */
-    protected static function hasTypedValueComparison(
+    private static function hasTypedValueComparison(
         PhpParser\Node\Expr\BinaryOp $conditional,
         FileSource $source,
     ): false|int {
@@ -1829,7 +1829,7 @@ protected static function hasTypedValueComparison(
         return false;
     }
 
-    protected static function hasIsACheck(
+    private static function hasIsACheck(
         PhpParser\Node\Expr\FuncCall $stmt,
         StatementsAnalyzer $source,
     ): bool {
@@ -1925,7 +1925,7 @@ private static function handleIsTypeCheck(
         return $if_types;
     }
 
-    protected static function hasCallableCheck(PhpParser\Node\Expr\FuncCall $stmt): bool
+    private static function hasCallableCheck(PhpParser\Node\Expr\FuncCall $stmt): bool
     {
         return $stmt->name instanceof PhpParser\Node\Name && strtolower($stmt->name->getFirst()) === 'is_callable';
     }
@@ -1933,7 +1933,7 @@ protected static function hasCallableCheck(PhpParser\Node\Expr\FuncCall $stmt):
     /**
      * @return Reconciler::RECONCILIATION_*
      */
-    protected static function hasClassExistsCheck(PhpParser\Node\Expr\FuncCall $stmt): int
+    private static function hasClassExistsCheck(PhpParser\Node\Expr\FuncCall $stmt): int
     {
         if ($stmt->name instanceof PhpParser\Node\Name
             && strtolower($stmt->name->getFirst()) === 'class_exists'
@@ -1959,7 +1959,7 @@ protected static function hasClassExistsCheck(PhpParser\Node\Expr\FuncCall $stmt
     /**
      * @return  0|1|2
      */
-    protected static function hasTraitExistsCheck(PhpParser\Node\Expr\FuncCall $stmt): int
+    private static function hasTraitExistsCheck(PhpParser\Node\Expr\FuncCall $stmt): int
     {
         if ($stmt->name instanceof PhpParser\Node\Name
             && strtolower($stmt->name->getFirst()) === 'trait_exists'
@@ -1982,22 +1982,22 @@ protected static function hasTraitExistsCheck(PhpParser\Node\Expr\FuncCall $stmt
         return 0;
     }
 
-    protected static function hasEnumExistsCheck(PhpParser\Node\Expr\FuncCall $stmt): bool
+    private static function hasEnumExistsCheck(PhpParser\Node\Expr\FuncCall $stmt): bool
     {
         return $stmt->name instanceof PhpParser\Node\Name && strtolower($stmt->name->getFirst()) === 'enum_exists';
     }
 
-    protected static function hasInterfaceExistsCheck(PhpParser\Node\Expr\FuncCall $stmt): bool
+    private static function hasInterfaceExistsCheck(PhpParser\Node\Expr\FuncCall $stmt): bool
     {
         return $stmt->name instanceof PhpParser\Node\Name && strtolower($stmt->name->getFirst()) === 'interface_exists';
     }
 
-    protected static function hasFunctionExistsCheck(PhpParser\Node\Expr\FuncCall $stmt): bool
+    private static function hasFunctionExistsCheck(PhpParser\Node\Expr\FuncCall $stmt): bool
     {
         return $stmt->name instanceof PhpParser\Node\Name && strtolower($stmt->name->getFirst()) === 'function_exists';
     }
 
-    protected static function hasInArrayCheck(PhpParser\Node\Expr\FuncCall $stmt): bool
+    private static function hasInArrayCheck(PhpParser\Node\Expr\FuncCall $stmt): bool
     {
         if ($stmt->name instanceof PhpParser\Node\Name
             && strtolower($stmt->name->getFirst()) === 'in_array'
@@ -2015,13 +2015,13 @@ protected static function hasInArrayCheck(PhpParser\Node\Expr\FuncCall $stmt): b
         return false;
     }
 
-    protected static function hasNonEmptyCountCheck(PhpParser\Node\Expr\FuncCall $stmt): bool
+    private static function hasNonEmptyCountCheck(PhpParser\Node\Expr\FuncCall $stmt): bool
     {
         return $stmt->name instanceof PhpParser\Node\Name &&
             in_array(strtolower($stmt->name->getFirst()), ['count', 'sizeof']);
     }
 
-    protected static function hasArrayKeyExistsCheck(PhpParser\Node\Expr\FuncCall $stmt): bool
+    private static function hasArrayKeyExistsCheck(PhpParser\Node\Expr\FuncCall $stmt): bool
     {
         return $stmt->name instanceof PhpParser\Node\Name && strtolower($stmt->name->getFirst()) === 'array_key_exists';
     }
diff --git a/src/Psalm/Internal/Analyzer/Statements/Expression/CallAnalyzer.php b/src/Psalm/Internal/Analyzer/Statements/Expression/CallAnalyzer.php
index 25b9f104cb3..f53816e5814 100644
--- a/src/Psalm/Internal/Analyzer/Statements/Expression/CallAnalyzer.php
+++ b/src/Psalm/Internal/Analyzer/Statements/Expression/CallAnalyzer.php
@@ -76,7 +76,7 @@
 /**
  * @internal
  */
-class CallAnalyzer
+abstract class CallAnalyzer
 {
     public static function collectSpecialInformation(
         FunctionLikeAnalyzer $source,
diff --git a/src/Psalm/Internal/Analyzer/StatementsAnalyzer.php b/src/Psalm/Internal/Analyzer/StatementsAnalyzer.php
index be5d5e48762..8f4d2e4c9e6 100644
--- a/src/Psalm/Internal/Analyzer/StatementsAnalyzer.php
+++ b/src/Psalm/Internal/Analyzer/StatementsAnalyzer.php
@@ -96,9 +96,9 @@
  */
 final class StatementsAnalyzer extends SourceAnalyzer
 {
-    protected FileAnalyzer $file_analyzer;
+    private readonly FileAnalyzer $file_analyzer;
 
-    protected Codebase $codebase;
+    private readonly Codebase $codebase;
 
     /**
      * @var array<string, CodeLocation>
diff --git a/src/Psalm/Internal/Codebase/Populator.php b/src/Psalm/Internal/Codebase/Populator.php
index 338d2278e74..1a5c2935503 100644
--- a/src/Psalm/Internal/Codebase/Populator.php
+++ b/src/Psalm/Internal/Codebase/Populator.php
@@ -865,7 +865,7 @@ private function inheritConstantsFromTrait(
         }
     }
 
-    protected function inheritMethodsFromParent(
+    private function inheritMethodsFromParent(
         ClassLikeStorage $storage,
         ClassLikeStorage $parent_storage,
     ): void {
diff --git a/src/Psalm/Internal/Codebase/VariableUseGraph.php b/src/Psalm/Internal/Codebase/VariableUseGraph.php
index f17154c5a1f..615f7482ee9 100644
--- a/src/Psalm/Internal/Codebase/VariableUseGraph.php
+++ b/src/Psalm/Internal/Codebase/VariableUseGraph.php
@@ -17,7 +17,7 @@
 final class VariableUseGraph extends DataFlowGraph
 {
     /** @var array<string, array<string, true>> */
-    protected array $backward_edges = [];
+    private array $backward_edges = [];
 
     /** @var array<string, DataFlowNode> */
     private array $nodes = [];
diff --git a/src/Psalm/Internal/Diff/AstDiffer.php b/src/Psalm/Internal/Diff/AstDiffer.php
index fcc2bd25edc..3c889711585 100644
--- a/src/Psalm/Internal/Diff/AstDiffer.php
+++ b/src/Psalm/Internal/Diff/AstDiffer.php
@@ -21,7 +21,7 @@
  *
  * @internal
  */
-class AstDiffer
+final class AstDiffer
 {
     /**
      * @param Closure(Stmt, Stmt, string, string, bool=): bool $is_equal
@@ -29,7 +29,7 @@ class AstDiffer
      * @param array<int, Stmt> $b
      * @return array{0:non-empty-list<array<int, int>>, 1: int, 2: int, 3: array<int, bool>}
      */
-    protected static function calculateTrace(
+    private static function calculateTrace(
         Closure $is_equal,
         array $a,
         array $b,
@@ -81,7 +81,7 @@ protected static function calculateTrace(
      * @return list<DiffElem>
      * @psalm-pure
      */
-    protected static function extractDiff(array $trace, int $x, int $y, array $a, array $b, array $bc): array
+    private static function extractDiff(array $trace, int $x, int $y, array $a, array $b, array $bc): array
     {
         $result = [];
         for ($d = count($trace) - 1; $d >= 0; --$d) {
diff --git a/src/Psalm/Internal/ExecutionEnvironment/BuildInfoCollector.php b/src/Psalm/Internal/ExecutionEnvironment/BuildInfoCollector.php
index aef34adfee4..0da2ea1dc62 100644
--- a/src/Psalm/Internal/ExecutionEnvironment/BuildInfoCollector.php
+++ b/src/Psalm/Internal/ExecutionEnvironment/BuildInfoCollector.php
@@ -28,7 +28,7 @@ final class BuildInfoCollector
     /**
      * Read environment variables.
      */
-    protected array $readEnv = [];
+    private array $readEnv = [];
 
     public function __construct(
         /**
@@ -70,7 +70,7 @@ public function collect(): array
      * @return $this
      * @psalm-suppress PossiblyUndefinedStringArrayOffset
      */
-    protected function fillTravisCi(): self
+    private function fillTravisCi(): self
     {
         if (isset($this->env['TRAVIS']) && $this->env['TRAVIS'] && isset($this->env['TRAVIS_JOB_ID'])) {
             $this->readEnv['CI_JOB_ID'] = $this->env['TRAVIS_JOB_ID'];
@@ -113,7 +113,7 @@ protected function fillTravisCi(): self
      *
      * @return $this
      */
-    protected function fillCircleCi(): self
+    private function fillCircleCi(): self
     {
         if (isset($this->env['CIRCLECI']) && $this->env['CIRCLECI'] && isset($this->env['CIRCLE_BUILD_NUM'])) {
             $this->env['CI_BUILD_NUMBER'] = $this->env['CIRCLE_BUILD_NUM'];
@@ -146,7 +146,7 @@ protected function fillCircleCi(): self
      * @psalm-suppress PossiblyUndefinedStringArrayOffset
      * @return $this
      */
-    protected function fillAppVeyor(): self
+    private function fillAppVeyor(): self
     {
         if (isset($this->env['APPVEYOR']) && $this->env['APPVEYOR'] && isset($this->env['APPVEYOR_BUILD_NUMBER'])) {
             $this->readEnv['CI_BUILD_NUMBER'] = $this->env['APPVEYOR_BUILD_NUMBER'];
@@ -193,7 +193,7 @@ protected function fillAppVeyor(): self
      *
      * @return $this
      */
-    protected function fillJenkins(): self
+    private function fillJenkins(): self
     {
         if (isset($this->env['JENKINS_URL']) && isset($this->env['BUILD_NUMBER'])) {
             $this->readEnv['CI_BUILD_NUMBER'] = $this->env['BUILD_NUMBER'];
@@ -217,7 +217,7 @@ protected function fillJenkins(): self
      * @psalm-suppress PossiblyUndefinedStringArrayOffset
      * @return $this
      */
-    protected function fillScrutinizer(): self
+    private function fillScrutinizer(): self
     {
         if (isset($this->env['SCRUTINIZER']) && $this->env['SCRUTINIZER']) {
             $this->readEnv['CI_JOB_ID'] = $this->env['SCRUTINIZER_INSPECTION_UUID'];
@@ -251,7 +251,7 @@ protected function fillScrutinizer(): self
      * @return $this
      * @psalm-suppress PossiblyUndefinedStringArrayOffset
      */
-    protected function fillGithubActions(): BuildInfoCollector
+    private function fillGithubActions(): BuildInfoCollector
     {
         if (isset($this->env['GITHUB_ACTIONS'])) {
             $this->env['CI_NAME'] = 'github-actions';
diff --git a/src/Psalm/Internal/ExecutionEnvironment/GitInfoCollector.php b/src/Psalm/Internal/ExecutionEnvironment/GitInfoCollector.php
index e23f5781a06..f659fef639d 100644
--- a/src/Psalm/Internal/ExecutionEnvironment/GitInfoCollector.php
+++ b/src/Psalm/Internal/ExecutionEnvironment/GitInfoCollector.php
@@ -29,7 +29,7 @@ final class GitInfoCollector
     /**
      * Git command.
      */
-    protected SystemCommandExecutor $executor;
+    private readonly SystemCommandExecutor $executor;
 
     /**
      * Constructor.
@@ -58,7 +58,7 @@ public function collect(): GitInfo
      *
      * @throws RuntimeException
      */
-    protected function collectBranch(): string
+    private function collectBranch(): string
     {
         $branchesResult = $this->executor->execute('git branch');
 
@@ -78,7 +78,7 @@ protected function collectBranch(): string
      *
      * @throws RuntimeException
      */
-    protected function collectCommit(): CommitInfo
+    private function collectCommit(): CommitInfo
     {
         $commitResult = $this->executor->execute('git log -1 --pretty=format:%H%n%aN%n%ae%n%cN%n%ce%n%s%n%at');
 
@@ -104,7 +104,7 @@ protected function collectCommit(): CommitInfo
      * @throws RuntimeException
      * @return list<RemoteInfo>
      */
-    protected function collectRemotes(): array
+    private function collectRemotes(): array
     {
         $remotesResult = $this->executor->execute('git remote -v');
 
diff --git a/src/Psalm/Internal/LanguageServer/LanguageServer.php b/src/Psalm/Internal/LanguageServer/LanguageServer.php
index 30e8758c504..df2f691cd68 100644
--- a/src/Psalm/Internal/LanguageServer/LanguageServer.php
+++ b/src/Psalm/Internal/LanguageServer/LanguageServer.php
@@ -118,10 +118,10 @@ final class LanguageServer extends Dispatcher
     /**
      * The AMP Delay token
      */
-    protected string $versionedAnalysisDelayToken = '';
+    private string $versionedAnalysisDelayToken = '';
 
     /** @var array<string,array<string,array{o:int, s: list<string>}>> */
-    protected array $issue_baseline = [];
+    private array $issue_baseline = [];
 
     /**
      * This should actually be a private property on `parent`
diff --git a/src/Psalm/Internal/PhpVisitor/AssignmentMapVisitor.php b/src/Psalm/Internal/PhpVisitor/AssignmentMapVisitor.php
index a1ea12f334e..de750effdf5 100644
--- a/src/Psalm/Internal/PhpVisitor/AssignmentMapVisitor.php
+++ b/src/Psalm/Internal/PhpVisitor/AssignmentMapVisitor.php
@@ -20,7 +20,7 @@ final class AssignmentMapVisitor extends PhpParser\NodeVisitorAbstract
     /**
      * @var array<string, array<string, bool>>
      */
-    protected array $assignment_map = [];
+    private array $assignment_map = [];
 
     public function __construct(protected ?string $this_class_name)
     {
diff --git a/src/Psalm/Internal/PhpVisitor/CheckTrivialExprVisitor.php b/src/Psalm/Internal/PhpVisitor/CheckTrivialExprVisitor.php
index 9c1bfa9de3f..1a3a14fdd2c 100644
--- a/src/Psalm/Internal/PhpVisitor/CheckTrivialExprVisitor.php
+++ b/src/Psalm/Internal/PhpVisitor/CheckTrivialExprVisitor.php
@@ -14,7 +14,7 @@ final class CheckTrivialExprVisitor extends PhpParser\NodeVisitorAbstract
     /**
      * @var array<int, PhpParser\Node\Expr>
      */
-    protected array $non_trivial_expr = [];
+    private array $non_trivial_expr = [];
 
     private function checkNonTrivialExpr(PhpParser\Node\Expr $node): bool
     {
diff --git a/src/Psalm/Internal/PhpVisitor/Reflector/ClassLikeDocblockParser.php b/src/Psalm/Internal/PhpVisitor/Reflector/ClassLikeDocblockParser.php
index d073445d4e1..e94a64ba10f 100644
--- a/src/Psalm/Internal/PhpVisitor/Reflector/ClassLikeDocblockParser.php
+++ b/src/Psalm/Internal/PhpVisitor/Reflector/ClassLikeDocblockParser.php
@@ -528,7 +528,7 @@ public static function parse(
      *     'psalm-property-read'|'property-write'|'psalm-property-write' $property_tag
      * @throws DocblockParseException
      */
-    protected static function addMagicPropertyToInfo(
+    private static function addMagicPropertyToInfo(
         Doc $comment,
         ClassLikeDocblockComment $info,
         array $specials,
diff --git a/src/Psalm/Internal/PhpVisitor/ShortClosureVisitor.php b/src/Psalm/Internal/PhpVisitor/ShortClosureVisitor.php
index 18137b22723..c10bc26ead5 100644
--- a/src/Psalm/Internal/PhpVisitor/ShortClosureVisitor.php
+++ b/src/Psalm/Internal/PhpVisitor/ShortClosureVisitor.php
@@ -16,7 +16,7 @@ final class ShortClosureVisitor extends PhpParser\NodeVisitorAbstract
     /**
      * @var array<string, bool>
      */
-    protected array $used_variables = [];
+    private array $used_variables = [];
 
     public function enterNode(PhpParser\Node $node): ?int
     {
diff --git a/src/Psalm/Internal/PhpVisitor/SimpleNameResolver.php b/src/Psalm/Internal/PhpVisitor/SimpleNameResolver.php
index e62040ae3e9..455a22696df 100644
--- a/src/Psalm/Internal/PhpVisitor/SimpleNameResolver.php
+++ b/src/Psalm/Internal/PhpVisitor/SimpleNameResolver.php
@@ -202,7 +202,7 @@ private function resolveType(?Node $node): ?Node
      * @param Stmt\Use_::TYPE_*  $type One of Stmt\Use_::TYPE_*
      * @return Name Resolved name, or original name with attribute
      */
-    protected function resolveName(Name $name, int $type): Name
+    private function resolveName(Name $name, int $type): Name
     {
         $resolvedName = $this->nameContext->getResolvedName($name, $type);
         if (null !== $resolvedName) {
@@ -220,12 +220,12 @@ protected function resolveName(Name $name, int $type): Name
         return $name;
     }
 
-    protected function resolveClassName(Name $name): Name
+    private function resolveClassName(Name $name): Name
     {
         return $this->resolveName($name, Stmt\Use_::TYPE_NORMAL);
     }
 
-    protected function addNamespacedName(Stmt\Class_ $node): void
+    private function addNamespacedName(Stmt\Class_ $node): void
     {
         $node->setAttribute('namespacedName', Name::concat(
             $this->nameContext->getNamespace(),
@@ -233,7 +233,7 @@ protected function addNamespacedName(Stmt\Class_ $node): void
         ));
     }
 
-    protected function resolveAttrGroups(Stmt\Class_ $node): void
+    private function resolveAttrGroups(Stmt\Class_ $node): void
     {
         foreach ($node->attrGroups as $attrGroup) {
             foreach ($attrGroup->attrs as $attr) {
@@ -242,7 +242,7 @@ protected function resolveAttrGroups(Stmt\Class_ $node): void
         }
     }
 
-    protected function resolveTrait(Stmt\Trait_ $node): void
+    private function resolveTrait(Stmt\Trait_ $node): void
     {
         $resolvedName = Name::concat($this->nameContext->getNamespace(), (string) $node->name);
 
diff --git a/src/Psalm/Internal/PluginManager/PluginList.php b/src/Psalm/Internal/PluginManager/PluginList.php
index 89c41e7be3a..42ff53e13e6 100644
--- a/src/Psalm/Internal/PluginManager/PluginList.php
+++ b/src/Psalm/Internal/PluginManager/PluginList.php
@@ -16,7 +16,7 @@
 /**
  * @internal
  */
-class PluginList
+final class PluginList
 {
     /** @var ?array<string,string> [pluginClass => packageName] */
     private ?array $all_plugins = null;
diff --git a/src/Psalm/Internal/PluginManager/PluginListFactory.php b/src/Psalm/Internal/PluginManager/PluginListFactory.php
index c6daf1b634b..d64f4af373a 100644
--- a/src/Psalm/Internal/PluginManager/PluginListFactory.php
+++ b/src/Psalm/Internal/PluginManager/PluginListFactory.php
@@ -18,7 +18,7 @@
 /**
  * @internal
  */
-class PluginListFactory
+final class PluginListFactory
 {
     public function __construct(private readonly string $project_root, private readonly string $psalm_root)
     {
diff --git a/src/Psalm/Internal/Provider/ClassLikeStorageCacheProvider.php b/src/Psalm/Internal/Provider/ClassLikeStorageCacheProvider.php
index c35c5e38238..2dfc5736357 100644
--- a/src/Psalm/Internal/Provider/ClassLikeStorageCacheProvider.php
+++ b/src/Psalm/Internal/Provider/ClassLikeStorageCacheProvider.php
@@ -26,7 +26,7 @@
 /**
  * @internal
  */
-class ClassLikeStorageCacheProvider
+final class ClassLikeStorageCacheProvider
 {
     private readonly Cache $cache;
 
diff --git a/src/Psalm/Internal/Provider/FileReferenceCacheProvider.php b/src/Psalm/Internal/Provider/FileReferenceCacheProvider.php
index 793e916989a..6a69e2018f3 100644
--- a/src/Psalm/Internal/Provider/FileReferenceCacheProvider.php
+++ b/src/Psalm/Internal/Provider/FileReferenceCacheProvider.php
@@ -28,7 +28,7 @@
  * @psalm-import-type FileMapType from Analyzer
  * @internal
  */
-class FileReferenceCacheProvider
+final class FileReferenceCacheProvider
 {
     private const REFERENCE_CACHE_NAME = 'references';
     private const CLASSLIKE_FILE_CACHE_NAME = 'classlike_files';
@@ -50,7 +50,7 @@ class FileReferenceCacheProvider
     private const FILE_MISSING_MEMBER_CACHE_NAME = 'file_missing_member';
     private const UNKNOWN_MEMBER_CACHE_NAME = 'unknown_member_references';
     private const METHOD_PARAM_USE_CACHE_NAME = 'method_param_uses';
-    protected Cache $cache;
+    private readonly Cache $cache;
 
     public function __construct(protected Config $config)
     {
diff --git a/src/Psalm/Internal/Provider/FileStorageCacheProvider.php b/src/Psalm/Internal/Provider/FileStorageCacheProvider.php
index 8419afd80fb..411d79ec9b4 100644
--- a/src/Psalm/Internal/Provider/FileStorageCacheProvider.php
+++ b/src/Psalm/Internal/Provider/FileStorageCacheProvider.php
@@ -25,7 +25,7 @@
 /**
  * @internal
  */
-class FileStorageCacheProvider
+final class FileStorageCacheProvider
 {
     private string $modified_timestamps = '';
 
@@ -73,7 +73,7 @@ public function writeToCache(FileStorage $storage, string $file_contents): void
     /**
      * @param lowercase-string $file_path
      */
-    protected function storeInCache(string $file_path, FileStorage  $storage): void
+    private function storeInCache(string $file_path, FileStorage  $storage): void
     {
         $cache_location = $this->getCacheLocationForPath($file_path, true);
         $this->cache->saveItem($cache_location, $storage);
@@ -119,7 +119,7 @@ private function getCacheHash(string $_unused_file_path, string $file_contents):
     /**
      * @param lowercase-string $file_path
      */
-    protected function loadFromCache(string $file_path): ?FileStorage
+    private function loadFromCache(string $file_path): ?FileStorage
     {
         $storage = $this->cache->getItem($this->getCacheLocationForPath($file_path));
         if ($storage instanceof FileStorage) {
diff --git a/src/Psalm/Internal/Provider/ParserCacheProvider.php b/src/Psalm/Internal/Provider/ParserCacheProvider.php
index 6c74fc06b22..36598b619d3 100644
--- a/src/Psalm/Internal/Provider/ParserCacheProvider.php
+++ b/src/Psalm/Internal/Provider/ParserCacheProvider.php
@@ -38,7 +38,7 @@
 /**
  * @internal
  */
-class ParserCacheProvider
+final class ParserCacheProvider
 {
     private const FILE_HASHES = 'file_hashes_json';
     private const PARSER_CACHE_DIRECTORY = 'php-parser';
@@ -51,14 +51,14 @@ class ParserCacheProvider
      *
      * @var array<string, string>|null
      */
-    protected ?array $existing_file_content_hashes = null;
+    private ?array $existing_file_content_hashes = null;
 
     /**
      * A map of recently-added filename hashes to contents hashes
      *
      * @var array<string, string>
      */
-    protected array $new_file_content_hashes = [];
+    private array $new_file_content_hashes = [];
 
     public function __construct(Config $config, private readonly bool $use_file_cache = true)
     {
diff --git a/src/Psalm/Internal/Provider/ProjectCacheProvider.php b/src/Psalm/Internal/Provider/ProjectCacheProvider.php
index 125e6f9c725..26b02f25ca4 100644
--- a/src/Psalm/Internal/Provider/ProjectCacheProvider.php
+++ b/src/Psalm/Internal/Provider/ProjectCacheProvider.php
@@ -22,7 +22,7 @@
  *
  * @internal
  */
-class ProjectCacheProvider
+final class ProjectCacheProvider
 {
     private const GOOD_RUN_NAME = 'good_run';
     private const COMPOSER_LOCK_HASH = 'composer_lock_hash';
@@ -116,7 +116,7 @@ public function updateComposerLockHash(): void
         file_put_contents($lock_hash_location, $this->composer_lock_hash);
     }
 
-    protected function getComposerLockHash(): string
+    private function getComposerLockHash(): string
     {
         if ($this->composer_lock_hash === null) {
             $cache_directory = Config::getInstance()->getCacheDirectory();
diff --git a/src/Psalm/Internal/Scanner/FileScanner.php b/src/Psalm/Internal/Scanner/FileScanner.php
index d8ba100c47f..d7bf827fecb 100644
--- a/src/Psalm/Internal/Scanner/FileScanner.php
+++ b/src/Psalm/Internal/Scanner/FileScanner.php
@@ -18,7 +18,7 @@
  * @internal
  * @psalm-consistent-constructor
  */
-class FileScanner implements FileSource
+final class FileScanner implements FileSource
 {
     public function __construct(public string $file_path, public string $file_name, public bool $will_analyze)
     {
diff --git a/src/Psalm/Issue/InvalidInterfaceImplementation.php b/src/Psalm/Issue/InvalidInterfaceImplementation.php
index 1acfa745e1f..ddaa2a62c3d 100644
--- a/src/Psalm/Issue/InvalidInterfaceImplementation.php
+++ b/src/Psalm/Issue/InvalidInterfaceImplementation.php
@@ -4,7 +4,7 @@
 
 namespace Psalm\Issue;
 
-class InvalidInterfaceImplementation extends ClassIssue
+final class InvalidInterfaceImplementation extends ClassIssue
 {
     final public const ERROR_LEVEL = -1;
     final public const SHORTCODE = 317;
diff --git a/src/Psalm/Issue/PrivateFinalMethod.php b/src/Psalm/Issue/PrivateFinalMethod.php
index 1df8c8421a0..889fbd4ef2a 100644
--- a/src/Psalm/Issue/PrivateFinalMethod.php
+++ b/src/Psalm/Issue/PrivateFinalMethod.php
@@ -4,7 +4,7 @@
 
 namespace Psalm\Issue;
 
-class PrivateFinalMethod extends MethodIssue
+final class PrivateFinalMethod extends MethodIssue
 {
     final public const ERROR_LEVEL = 2;
     final public const SHORTCODE = 320;
diff --git a/src/Psalm/Issue/RiskyCast.php b/src/Psalm/Issue/RiskyCast.php
index 6f58ecdcf2e..f4cb5da41b5 100644
--- a/src/Psalm/Issue/RiskyCast.php
+++ b/src/Psalm/Issue/RiskyCast.php
@@ -4,7 +4,7 @@
 
 namespace Psalm\Issue;
 
-class RiskyCast extends CodeIssue
+final class RiskyCast extends CodeIssue
 {
     final public const ERROR_LEVEL = 3;
     final public const SHORTCODE = 313;
diff --git a/src/Psalm/Issue/UnusedBaselineEntry.php b/src/Psalm/Issue/UnusedBaselineEntry.php
index 266ec1e8b4c..dd74a2239d1 100644
--- a/src/Psalm/Issue/UnusedBaselineEntry.php
+++ b/src/Psalm/Issue/UnusedBaselineEntry.php
@@ -4,7 +4,7 @@
 
 namespace Psalm\Issue;
 
-class UnusedBaselineEntry extends ClassIssue
+final class UnusedBaselineEntry extends ClassIssue
 {
     final public const ERROR_LEVEL = -1;
     final public const SHORTCODE = 316;
diff --git a/src/Psalm/IssueBuffer.php b/src/Psalm/IssueBuffer.php
index 8008513c792..e2834f1eb37 100644
--- a/src/Psalm/IssueBuffer.php
+++ b/src/Psalm/IssueBuffer.php
@@ -86,39 +86,39 @@ final class IssueBuffer
     /**
      * @var array<string, list<IssueData>>
      */
-    protected static array $issues_data = [];
+    private static array $issues_data = [];
 
     /**
      * @var array<int, array>
      */
-    protected static array $console_issues = [];
+    private static array $console_issues = [];
 
     /**
      * @var array<string, int>
      */
-    protected static array $fixable_issue_counts = [];
+    private static array $fixable_issue_counts = [];
 
-    protected static int $error_count = 0;
+    private static int $error_count = 0;
 
     /**
      * @var array<string, bool>
      */
-    protected static array $emitted = [];
+    private static array $emitted = [];
 
-    protected static int $recording_level = 0;
+    private static int $recording_level = 0;
 
     /** @var array<int, array<int, CodeIssue>> */
-    protected static array $recorded_issues = [];
+    private static array $recorded_issues = [];
 
     /**
      * @var array<string, array<int, int>>
      */
-    protected static array $unused_suppressions = [];
+    private static array $unused_suppressions = [];
 
     /**
      * @var array<string, array<int, bool>>
      */
-    protected static array $used_suppressions = [];
+    private static array $used_suppressions = [];
 
     /** @var array<array-key,mixed> */
     private static array $server = [];
@@ -887,7 +887,7 @@ public static function getOutput(
         return $output->create();
     }
 
-    protected static function alreadyEmitted(string $message): bool
+    private static function alreadyEmitted(string $message): bool
     {
         $sham = sha1($message);
 
diff --git a/src/Psalm/Progress/DefaultProgress.php b/src/Psalm/Progress/DefaultProgress.php
index 57024cbf72f..59381fa938e 100644
--- a/src/Psalm/Progress/DefaultProgress.php
+++ b/src/Psalm/Progress/DefaultProgress.php
@@ -9,7 +9,7 @@
 use function str_repeat;
 use function strlen;
 
-class DefaultProgress extends LongProgress
+final class DefaultProgress extends LongProgress
 {
     private const TOO_MANY_FILES = 1_500;
 
diff --git a/src/Psalm/Report/CodeClimateReport.php b/src/Psalm/Report/CodeClimateReport.php
index 9fd215026f0..61027d6371b 100644
--- a/src/Psalm/Report/CodeClimateReport.php
+++ b/src/Psalm/Report/CodeClimateReport.php
@@ -39,7 +39,7 @@ public function create(): string
      * convert our own severity to CodeClimate format
      * Values can be : info, minor, major, critical, or blocker
      */
-    protected function convertSeverity(string $input): string
+    private function convertSeverity(string $input): string
     {
         if (Config::REPORT_INFO === $input) {
             return 'info';
@@ -58,7 +58,7 @@ protected function convertSeverity(string $input): string
     /**
      * calculate a unique fingerprint for a given issue
      */
-    protected function calculateFingerprint(IssueData $issue): string
+    private function calculateFingerprint(IssueData $issue): string
     {
         return md5($issue->type.$issue->message.$issue->file_name.$issue->from.$issue->to);
     }
diff --git a/src/Psalm/SourceControl/Git/CommitInfo.php b/src/Psalm/SourceControl/Git/CommitInfo.php
index d10bbb41c0b..e0e70bad284 100644
--- a/src/Psalm/SourceControl/Git/CommitInfo.php
+++ b/src/Psalm/SourceControl/Git/CommitInfo.php
@@ -14,37 +14,37 @@ final class CommitInfo
     /**
      * Commit ID.
      */
-    protected ?string $id = null;
+    private ?string $id = null;
 
     /**
      * Author name.
      */
-    protected ?string $author_name = null;
+    private ?string $author_name = null;
 
     /**
      * Author email.
      */
-    protected ?string $author_email = null;
+    private ?string $author_email = null;
 
     /**
      * Committer name.
      */
-    protected ?string $committer_name = null;
+    private ?string $committer_name = null;
 
     /**
      * Committer email.
      */
-    protected ?string $committer_email = null;
+    private ?string $committer_email = null;
 
     /**
      * Commit message.
      */
-    protected ?string $message = null;
+    private ?string $message = null;
 
     /**
      * Commit message.
      */
-    protected ?int $date = null;
+    private ?int $date = null;
 
     public function toArray(): array
     {
diff --git a/src/Psalm/SourceControl/Git/RemoteInfo.php b/src/Psalm/SourceControl/Git/RemoteInfo.php
index 91bf9a9b44a..ebb551b2186 100644
--- a/src/Psalm/SourceControl/Git/RemoteInfo.php
+++ b/src/Psalm/SourceControl/Git/RemoteInfo.php
@@ -14,12 +14,12 @@ final class RemoteInfo
     /**
      * Remote name.
      */
-    protected ?string $name = null;
+    private ?string $name = null;
 
     /**
      * Remote URL.
      */
-    protected ?string $url = null;
+    private ?string $url = null;
 
     public function toArray(): array
     {