diff --git a/src/DI/Autowiring.php b/src/DI/Autowiring.php
index a351e724c..3fa4a25da 100644
--- a/src/DI/Autowiring.php
+++ b/src/DI/Autowiring.php
@@ -61,7 +61,7 @@ public function getByType(string $type, bool $throw = false): ?string
 		} else {
 			$list = $types[$type];
 			natsort($list);
-			$hint = count($list) === 2 && ($tmp = strpos($list[0], '.') xor strpos($list[1], '.'))
+			$hint = count($list) === 2 && ($tmp = str_contains($list[0], '.') xor str_contains($list[1], '.'))
 				? '. If you want to overwrite service ' . $list[$tmp ? 0 : 1] . ', give it proper name.'
 				: '';
 			throw new ServiceCreationException(sprintf(
diff --git a/src/DI/CompilerExtension.php b/src/DI/CompilerExtension.php
index ab8db4e04..3a258989f 100644
--- a/src/DI/CompilerExtension.php
+++ b/src/DI/CompilerExtension.php
@@ -137,7 +137,7 @@ public function getInitialization(): Nette\PhpGenerator\Closure
 	 */
 	public function prefix(string $id): string
 	{
-		return substr_replace($id, $this->name . '.', substr($id, 0, 1) === '@' ? 1 : 0, 0);
+		return substr_replace($id, $this->name . '.', str_starts_with($id, '@') ? 1 : 0, 0);
 	}
 
 
diff --git a/src/DI/Config/Adapters/NeonAdapter.php b/src/DI/Config/Adapters/NeonAdapter.php
index a6474f7a9..aed858203 100644
--- a/src/DI/Config/Adapters/NeonAdapter.php
+++ b/src/DI/Config/Adapters/NeonAdapter.php
@@ -40,7 +40,7 @@ public function process(array $arr): array
 	{
 		$res = [];
 		foreach ($arr as $key => $val) {
-			if (is_string($key) && substr($key, -1) === self::PREVENT_MERGING_SUFFIX) {
+			if (is_string($key) && str_ends_with($key, self::PREVENT_MERGING_SUFFIX)) {
 				if (!is_array($val) && $val !== null) {
 					throw new Nette\DI\InvalidConfigurationException(sprintf(
 						"Replacing operator is available only for arrays, item '%s' is not array.",
@@ -66,7 +66,7 @@ public function process(array $arr): array
 					$val = $tmp;
 				} else {
 					$tmp = $this->process([$val->value]);
-					if (is_string($tmp[0]) && strpos($tmp[0], '?') !== false) {
+					if (is_string($tmp[0]) && str_contains($tmp[0], '?')) {
 						trigger_error('Operator ? is deprecated in config files.', E_USER_DEPRECATED);
 					}
 					$val = new Statement($tmp[0], $this->process($val->attributes));
diff --git a/src/DI/Definitions/AccessorDefinition.php b/src/DI/Definitions/AccessorDefinition.php
index e147ea4ab..b126d1ba2 100644
--- a/src/DI/Definitions/AccessorDefinition.php
+++ b/src/DI/Definitions/AccessorDefinition.php
@@ -69,7 +69,7 @@ public function setReference(string|Reference $reference): static
 		if ($reference instanceof Reference) {
 			$this->reference = $reference;
 		} else {
-			$this->reference = substr($reference, 0, 1) === '@'
+			$this->reference = str_starts_with($reference, '@')
 				? new Reference(substr($reference, 1))
 				: Reference::fromType($reference);
 		}
diff --git a/src/DI/Definitions/LocatorDefinition.php b/src/DI/Definitions/LocatorDefinition.php
index 2450631c9..5f0928ebe 100644
--- a/src/DI/Definitions/LocatorDefinition.php
+++ b/src/DI/Definitions/LocatorDefinition.php
@@ -61,7 +61,7 @@ public function setReferences(array $references): static
 	{
 		$this->references = [];
 		foreach ($references as $name => $ref) {
-			$this->references[$name] = substr($ref, 0, 1) === '@'
+			$this->references[$name] = str_starts_with($ref, '@')
 				? new Reference(substr($ref, 1))
 				: Reference::fromType($ref);
 		}
diff --git a/src/DI/Definitions/Reference.php b/src/DI/Definitions/Reference.php
index d0b502ea1..c303b01ea 100644
--- a/src/DI/Definitions/Reference.php
+++ b/src/DI/Definitions/Reference.php
@@ -26,7 +26,7 @@ final class Reference
 
 	public static function fromType(string $value): static
 	{
-		if (strpos($value, '\\') === false) {
+		if (!str_contains($value, '\\')) {
 			$value = '\\' . $value;
 		}
 		return new static($value);
@@ -47,13 +47,13 @@ public function getValue(): string
 
 	public function isName(): bool
 	{
-		return strpos($this->value, '\\') === false && $this->value !== self::SELF;
+		return !str_contains($this->value, '\\') && $this->value !== self::SELF;
 	}
 
 
 	public function isType(): bool
 	{
-		return strpos($this->value, '\\') !== false;
+		return str_contains($this->value, '\\');
 	}
 
 
diff --git a/src/DI/Definitions/Statement.php b/src/DI/Definitions/Statement.php
index 616b88360..9c6377386 100644
--- a/src/DI/Definitions/Statement.php
+++ b/src/DI/Definitions/Statement.php
@@ -48,9 +48,9 @@ public function __construct(string|array|Definition|Reference|null $entity, arra
 		if (is_string($entity) && Strings::contains($entity, '::') && !Strings::contains($entity, '?')) {
 			$entity = explode('::', $entity, 2);
 		}
-		if (is_string($entity) && substr($entity, 0, 1) === '@') { // normalize @service to Reference
+		if (is_string($entity) && str_starts_with($entity, '@')) { // normalize @service to Reference
 			$entity = new Reference(substr($entity, 1));
-		} elseif (is_array($entity) && is_string($entity[0]) && substr($entity[0], 0, 1) === '@') {
+		} elseif (is_array($entity) && is_string($entity[0]) && str_starts_with($entity[0], '@')) {
 			$entity[0] = new Reference(substr($entity[0], 1));
 		}
 
diff --git a/src/DI/DependencyChecker.php b/src/DI/DependencyChecker.php
index 79b5a467e..05b5e009f 100644
--- a/src/DI/DependencyChecker.php
+++ b/src/DI/DependencyChecker.php
@@ -140,7 +140,7 @@ class_uses($name),
 
 		$flip = array_flip($classes);
 		foreach ($functions as $name) {
-			if (strpos($name, '::')) {
+			if (str_contains($name, '::')) {
 				$method = new ReflectionMethod($name);
 				$class = $method->getDeclaringClass();
 				if (isset($flip[$class->name])) {
diff --git a/src/DI/Extensions/InjectExtension.php b/src/DI/Extensions/InjectExtension.php
index df2445199..d7df36ad3 100644
--- a/src/DI/Extensions/InjectExtension.php
+++ b/src/DI/Extensions/InjectExtension.php
@@ -89,7 +89,7 @@ public static function getInjectMethods(string $class): array
 	{
 		$classes = [];
 		foreach (get_class_methods($class) as $name) {
-			if (substr($name, 0, 6) === 'inject') {
+			if (str_starts_with($name, 'inject')) {
 				$classes[$name] = (new \ReflectionMethod($class, $name))->getDeclaringClass()->name;
 			}
 		}
@@ -114,7 +114,7 @@ public static function getInjectProperties(string $class): array
 			if ($hasAttr || DI\Helpers::parseAnnotation($rp, 'inject') !== null) {
 				if ($type = Reflection::getPropertyType($rp)) {
 				} elseif (!$hasAttr && ($type = DI\Helpers::parseAnnotation($rp, 'var'))) {
-					if (strpos($type, '|') !== false) {
+					if (str_contains($type, '|')) {
 						throw new Nette\InvalidStateException(sprintf(
 							'The %s is not expected to have a union type.',
 							Reflection::toString($rp),
diff --git a/src/DI/Extensions/SearchExtension.php b/src/DI/Extensions/SearchExtension.php
index c05460a2e..c6640091b 100644
--- a/src/DI/Extensions/SearchExtension.php
+++ b/src/DI/Extensions/SearchExtension.php
@@ -139,7 +139,7 @@ private static function buildNameRegexp(array $masks): ?string
 	{
 		$res = [];
 		foreach ((array) $masks as $mask) {
-			$mask = (strpos($mask, '\\') === false ? '**\\' : '') . $mask;
+			$mask = (str_contains($mask, '\\') ? '' : '**\\') . $mask;
 			$mask = preg_quote($mask, '#');
 			$mask = str_replace('\*\*\\\\', '(.*\\\\)?', $mask);
 			$mask = str_replace('\\\\\*\*', '(\\\\.*)?', $mask);
diff --git a/src/DI/Extensions/ServicesExtension.php b/src/DI/Extensions/ServicesExtension.php
index a00d4b241..27e4a2a2a 100644
--- a/src/DI/Extensions/ServicesExtension.php
+++ b/src/DI/Extensions/ServicesExtension.php
@@ -72,7 +72,7 @@ private function loadDefinition(?string $name, \stdClass $config): void
 
 		} catch (\Exception $e) {
 			$message = $e->getMessage();
-			if ($name && !Nette\Utils\Strings::startsWith($message, '[Service ')) {
+			if ($name && !str_starts_with($message, '[Service ')) {
 				$message = "[Service '$name']\n$message";
 			}
 			throw new Nette\DI\InvalidConfigurationException($message, 0, $e);
diff --git a/src/DI/PhpGenerator.php b/src/DI/PhpGenerator.php
index 44a3d439a..44f732948 100644
--- a/src/DI/PhpGenerator.php
+++ b/src/DI/PhpGenerator.php
@@ -126,7 +126,7 @@ public function formatStatement(Statement $statement): string
 				switch (true) {
 					case $entity[1][0] === '$': // property getter, setter or appender
 						$name = substr($entity[1], 1);
-						if ($append = (substr($name, -2) === '[]')) {
+						if ($append = (str_ends_with($name, '[]'))) {
 							$name = substr($name, 0, -2);
 						}
 						$prop = $entity[0] instanceof Reference
@@ -138,7 +138,7 @@ public function formatStatement(Statement $statement): string
 
 					case $entity[0] instanceof Statement:
 						$inner = $this->formatPhp('?', [$entity[0]]);
-						if (substr($inner, 0, 4) === 'new ') {
+						if (str_starts_with($inner, 'new ')) {
 							$inner = "($inner)";
 						}
 						return $this->formatPhp("$inner->?(...?)", [$entity[1], $arguments]);
diff --git a/src/DI/Resolver.php b/src/DI/Resolver.php
index 8b49d3dd6..b7c6b8559 100644
--- a/src/DI/Resolver.php
+++ b/src/DI/Resolver.php
@@ -259,7 +259,7 @@ public function completeStatement(Statement $statement, bool $currentServiceAllo
 					case $entity[0] instanceof Reference:
 						if ($entity[1][0] === '$') { // property getter, setter or appender
 							Validators::assert($arguments, 'list:0..1', "setup arguments for '" . Nette\Utils\Callback::toString($entity) . "'");
-							if (!$arguments && substr($entity[1], -2) === '[]') {
+							if (!$arguments && str_ends_with($entity[1], '[]')) {
 								throw new ServiceCreationException(sprintf('Missing argument for %s.', $entity[1]));
 							}
 						} elseif (
@@ -287,7 +287,7 @@ public function completeStatement(Statement $statement, bool $currentServiceAllo
 			$arguments = $this->completeArguments($arguments);
 
 		} catch (ServiceCreationException $e) {
-			if (!strpos($e->getMessage(), "\nRelated to")) {
+			if (!str_contains($e->getMessage(), "\nRelated to")) {
 				if (is_string($entity)) {
 					$desc = $entity . '::__construct()';
 				} else {
@@ -432,7 +432,7 @@ public function addDependency(\ReflectionClass|\ReflectionFunctionAbstract|strin
 	private function completeException(\Exception $e, Definition $def): ServiceCreationException
 	{
 		$message = $e->getMessage();
-		if ($e instanceof ServiceCreationException && Strings::startsWith($message, '[Service ')) {
+		if ($e instanceof ServiceCreationException && str_starts_with($message, '[Service ')) {
 			return $e;
 		}
 
@@ -460,7 +460,7 @@ private function convertReferences(array $arguments): array
 					$val = new Statement([new Reference($pair[0]), '$' . $pair[1]]);
 				}
 
-			} elseif (is_string($val) && substr($val, 0, 2) === '@@') { // escaped text @@
+			} elseif (is_string($val) && str_starts_with($val, '@@')) { // escaped text @@
 				$val = substr($val, 1);
 			}
 		});