diff --git a/UPGRADE-5.0.md b/UPGRADE-5.0.md
index 578ffaaaa..92a1f90bc 100644
--- a/UPGRADE-5.0.md
+++ b/UPGRADE-5.0.md
@@ -21,6 +21,39 @@ $logger->pushHandler(new \Sentry\Monolog\LogsHandler());
 
 To continue sending Monolog records to Sentry issues instead, use `Sentry\Monolog\LogToSentryIssueHandler` for log messages or `Sentry\Monolog\ExceptionToSentryIssueHandler` for exceptions.
 
+### Hub APIs Removed
+
+The Hub API has been removed. This includes:
+
+- **Removed classes and interfaces:**
+  - `Sentry\State\Hub`
+  - `Sentry\State\HubAdapter`
+  - `Sentry\State\HubInterface`
+
+- **Removed methods:**
+  - `SentrySdk::getCurrentHub()`
+  - `SentrySdk::setCurrentHub()`
+
+The SDK now exposes runtime state directly through `SentrySdk`, global helpers, and `Scope`:
+
+```php
+// Before (4.x)
+\Sentry\SentrySdk::getCurrentHub()->configureScope(static function (\Sentry\State\Scope $scope): void {
+    $scope->setTag('feature', 'checkout');
+});
+
+// After (5.0)
+\Sentry\configureScope(static function (\Sentry\State\Scope $scope): void {
+    $scope->setTag('feature', 'checkout');
+});
+```
+
+Use `SentrySdk::getClient()` for the active client, `SentrySdk::getGlobalScope()` for process-global data, and `SentrySdk::getIsolationScope()` for the current runtime isolation scope. Use the capture helpers such as `captureMessage()`, `captureException()`, and `captureEvent()` to send events.
+
+Use `configureScope()` to mutate the current isolation scope, `withIsolationScope()` to run code with a temporary forked scope, and `startTransaction()` to start manual tracing instrumentation.
+
+`SentrySdk::init()` no longer returns a Hub instance. It now returns `void`.
+
 ### Metrics API Removed
 
 The entire Metrics API has been removed as it is no longer supported. This includes:
diff --git a/analysis-baseline.toml b/analysis-baseline.toml
index 2c30c8e02..bb9bc9876 100644
--- a/analysis-baseline.toml
+++ b/analysis-baseline.toml
@@ -1368,18 +1368,6 @@ code = "possibly-invalid-argument"
 message = '''Possible argument type mismatch for argument #1 of `Sentry\StacktraceBuilder::buildFromBacktrace`: expected `list<array{'args'?: array<array-key, mixed>, 'class'?: class-string, 'file'?: string, 'function'?: string, 'line'?: int, 'type'?: string}>`, but possibly received `array<array-key, mixed>`.'''
 count = 1
 
-[[issues]]
-file = "src/State/Hub.php"
-code = "mixed-operand"
-message = "Right operand in `<` comparison has `mixed` type."
-count = 1
-
-[[issues]]
-file = "src/State/Hub.php"
-code = "possibly-null-operand"
-message = "Left operand in `<` comparison might be `null` (type `float|null`)."
-count = 1
-
 [[issues]]
 file = "src/State/Scope.php"
 code = "impossible-condition"
diff --git a/src/Integration/ModulesIntegration.php b/src/Integration/ModulesIntegration.php
index f1234f355..9e5ee8c16 100644
--- a/src/Integration/ModulesIntegration.php
+++ b/src/Integration/ModulesIntegration.php
@@ -28,8 +28,6 @@ public function setupOnce(): void
         Scope::addGlobalEventProcessor(static function (Event $event): Event {
             $integration = SentrySdk::getClient()->getIntegration(self::class);
 
-            // The integration could be bound to a client that is not the one
-            // attached to the current hub. If this is the case, bail out
             if ($integration !== null) {
                 $event->setModules(self::getComposerPackages());
             }
diff --git a/src/Integration/TransactionIntegration.php b/src/Integration/TransactionIntegration.php
index 746584dab..13c7bfe51 100644
--- a/src/Integration/TransactionIntegration.php
+++ b/src/Integration/TransactionIntegration.php
@@ -26,8 +26,6 @@ public function setupOnce(): void
         Scope::addGlobalEventProcessor(static function (Event $event, EventHint $hint): Event {
             $integration = SentrySdk::getClient()->getIntegration(self::class);
 
-            // The client bound to the current hub, if any, could not have this
-            // integration enabled. If this is the case, bail out
             if ($integration === null) {
                 return $event;
             }
diff --git a/src/SentrySdk.php b/src/SentrySdk.php
index 3822d4a28..d01434fec 100644
--- a/src/SentrySdk.php
+++ b/src/SentrySdk.php
@@ -6,8 +6,6 @@
 
 use Sentry\Logs\Logs;
 use Sentry\Metrics\TraceMetrics;
-use Sentry\State\HubAdapter;
-use Sentry\State\HubInterface;
 use Sentry\State\RuntimeContext;
 use Sentry\State\RuntimeContextManager;
 use Sentry\State\Scope;
@@ -37,38 +35,15 @@ private function __construct()
     }
 
     /**
-     * Initializes the SDK by binding the client to the global scope and reset
+     * Initializes the SDK by binding the client to the global scope and resetting
      * the current local runtime state.
      */
-    public static function init(?ClientInterface $client = null): HubInterface
+    public static function init(?ClientInterface $client = null): void
     {
         if ($client !== null) {
             self::getGlobalScope()->setClient($client);
         }
         self::$runtimeContextManager = new RuntimeContextManager();
-
-        return self::getCurrentHub();
-    }
-
-    public static function getCurrentHub(): HubInterface
-    {
-        return HubAdapter::getInstance();
-    }
-
-    /**
-     * Sets the current hub.
-     *
-     * If called while an explicit runtime context is active, the hub update is
-     * scoped to that active context only. Otherwise, it updates the baseline
-     * hub used by the global fallback context and future contexts.
-     *
-     * @param HubInterface $hub The hub to set
-     */
-    public static function setCurrentHub(HubInterface $hub): HubInterface
-    {
-        self::getGlobalScope()->setClient($hub->getClient());
-
-        return $hub;
     }
 
     public static function getGlobalScope(): Scope
diff --git a/src/State/Hub.php b/src/State/Hub.php
deleted file mode 100644
index 82597e79c..000000000
--- a/src/State/Hub.php
+++ /dev/null
@@ -1,283 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Sentry\State;
-
-use Sentry\Attachment\Attachment;
-use Sentry\Breadcrumb;
-use Sentry\CheckIn;
-use Sentry\CheckInStatus;
-use Sentry\ClientInterface;
-use Sentry\Event;
-use Sentry\EventHint;
-use Sentry\EventId;
-use Sentry\Integration\IntegrationInterface;
-use Sentry\MonitorConfig;
-use Sentry\NoOpClient;
-use Sentry\Severity;
-use Sentry\Tracing\Span;
-use Sentry\Tracing\Transaction;
-use Sentry\Tracing\TransactionContext;
-use Sentry\Tracing\TransactionSampler;
-
-/**
- * This class is a basic implementation of the {@see HubInterface} interface.
- */
-class Hub implements HubInterface
-{
-    /**
-     * @var Layer[] The stack of client/scope pairs
-     */
-    private $stack = [];
-
-    /**
-     * @var EventId|null The ID of the last captured event
-     */
-    private $lastEventId;
-
-    /**
-     * Hub constructor.
-     *
-     * @param ClientInterface $client The client bound to the hub
-     * @param Scope|null      $scope  The scope bound to the hub
-     */
-    public function __construct(ClientInterface $client, ?Scope $scope = null)
-    {
-        $this->stack[] = new Layer($client, $scope ?? new Scope());
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function getClient(): ClientInterface
-    {
-        return $this->getStackTop()->getClient();
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function getLastEventId(): ?EventId
-    {
-        return $this->lastEventId;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function pushScope(): Scope
-    {
-        $clonedScope = clone $this->getScope();
-
-        $this->stack[] = new Layer($this->getClient(), $clonedScope);
-
-        return $clonedScope;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function popScope(): bool
-    {
-        if (\count($this->stack) === 1) {
-            return false;
-        }
-
-        return array_pop($this->stack) !== null;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function withScope(callable $callback)
-    {
-        $scope = $this->pushScope();
-
-        try {
-            return $callback($scope);
-        } finally {
-            $this->popScope();
-        }
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function configureScope(callable $callback): void
-    {
-        $callback($this->getScope());
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function bindClient(ClientInterface $client): void
-    {
-        $layer = $this->getStackTop();
-        $layer->setClient($client);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function captureMessage(string $message, ?Severity $level = null, ?EventHint $hint = null): ?EventId
-    {
-        return $this->lastEventId = $this->getClient()->captureMessage($message, $level, $this->getScope(), $hint);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function captureException(\Throwable $exception, ?EventHint $hint = null): ?EventId
-    {
-        return $this->lastEventId = $this->getClient()->captureException($exception, $this->getScope(), $hint);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function captureEvent(Event $event, ?EventHint $hint = null): ?EventId
-    {
-        return $this->lastEventId = $this->getClient()->captureEvent($event, $hint, $this->getScope());
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function captureLastError(?EventHint $hint = null): ?EventId
-    {
-        return $this->lastEventId = $this->getClient()->captureLastError($this->getScope(), $hint);
-    }
-
-    /**
-     * {@inheritdoc}
-     *
-     * @param int|float|null $duration
-     */
-    public function captureCheckIn(string $slug, CheckInStatus $status, $duration = null, ?MonitorConfig $monitorConfig = null, ?string $checkInId = null): ?string
-    {
-        $client = $this->getClient();
-
-        if ($client instanceof NoOpClient) {
-            return null;
-        }
-
-        $options = $client->getOptions();
-        $event = Event::createCheckIn();
-        $checkIn = new CheckIn(
-            $slug,
-            $status,
-            $checkInId,
-            $options->getRelease(),
-            $options->getEnvironment(),
-            $duration,
-            $monitorConfig
-        );
-        $event->setCheckIn($checkIn);
-        $this->captureEvent($event);
-
-        return $checkIn->getId();
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function addBreadcrumb(Breadcrumb $breadcrumb): bool
-    {
-        $client = $this->getClient();
-
-        // No point in storing breadcrumbs if the client will never send them
-        if ($client instanceof NoOpClient) {
-            return false;
-        }
-
-        $options = $client->getOptions();
-        $beforeBreadcrumbCallback = $options->getBeforeBreadcrumbCallback();
-        $maxBreadcrumbs = $options->getMaxBreadcrumbs();
-
-        if ($maxBreadcrumbs <= 0) {
-            return false;
-        }
-
-        $breadcrumb = $beforeBreadcrumbCallback($breadcrumb);
-
-        if ($breadcrumb !== null) {
-            $this->getScope()->addBreadcrumb($breadcrumb, $maxBreadcrumbs);
-        }
-
-        return $breadcrumb !== null;
-    }
-
-    public function addAttachment(Attachment $attachment): bool
-    {
-        // No point in storing attachments if the client will never send them
-        if ($this->getClient() instanceof NoOpClient) {
-            return false;
-        }
-
-        $this->getScope()->addAttachment($attachment);
-
-        return true;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function getIntegration(string $className): ?IntegrationInterface
-    {
-        return $this->getClient()->getIntegration($className);
-    }
-
-    /**
-     * {@inheritdoc}
-     *
-     * @param array<string, mixed> $customSamplingContext Additional context that will be passed to the {@see SamplingContext}
-     */
-    public function startTransaction(TransactionContext $context, array $customSamplingContext = []): Transaction
-    {
-        return TransactionSampler::startTransaction($this->getClient()->getOptions(), $context, $customSamplingContext);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function getTransaction(): ?Transaction
-    {
-        return $this->getScope()->getTransaction();
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function setSpan(?Span $span): HubInterface
-    {
-        $this->getScope()->setSpan($span);
-
-        return $this;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function getSpan(): ?Span
-    {
-        return $this->getScope()->getSpan();
-    }
-
-    /**
-     * Gets the scope bound to the top of the stack.
-     */
-    private function getScope(): Scope
-    {
-        return $this->getStackTop()->getScope();
-    }
-
-    /**
-     * Gets the topmost client/layer pair in the stack.
-     */
-    private function getStackTop(): Layer
-    {
-        return $this->stack[\count($this->stack) - 1];
-    }
-}
diff --git a/src/State/HubAdapter.php b/src/State/HubAdapter.php
deleted file mode 100644
index b376b4cd7..000000000
--- a/src/State/HubAdapter.php
+++ /dev/null
@@ -1,226 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Sentry\State;
-
-use Sentry\Attachment\Attachment;
-use Sentry\Breadcrumb;
-use Sentry\CheckInStatus;
-use Sentry\ClientInterface;
-use Sentry\Event;
-use Sentry\EventHint;
-use Sentry\EventId;
-use Sentry\Integration\IntegrationInterface;
-use Sentry\MonitorConfig;
-use Sentry\NoOpClient;
-use Sentry\SentrySdk;
-use Sentry\Severity;
-use Sentry\Tracing\Span;
-use Sentry\Tracing\Transaction;
-use Sentry\Tracing\TransactionContext;
-use Sentry\Tracing\TransactionSampler;
-
-/**
- * An implementation of {@see HubInterface} that uses {@see SentrySdk} internally
- * to manage the current hub.
- */
-final class HubAdapter implements HubInterface
-{
-    /**
-     * @var self|null The single instance which forwards all calls to {@see SentrySdk}
-     */
-    private static $instance;
-
-    /**
-     * Constructor.
-     */
-    private function __construct()
-    {
-    }
-
-    /**
-     * Gets the instance of this class. This is a singleton, so once initialized
-     * you will always get the same instance.
-     */
-    public static function getInstance(): self
-    {
-        if (self::$instance === null) {
-            self::$instance = new self();
-        }
-
-        return self::$instance;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function getClient(): ClientInterface
-    {
-        return SentrySdk::getClient();
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function getLastEventId(): ?EventId
-    {
-        return SentrySdk::getIsolationScope()->getLastEventId();
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function withScope(callable $callback)
-    {
-        return \Sentry\withIsolationScope($callback);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function configureScope(callable $callback): void
-    {
-        $callback(SentrySdk::getIsolationScope());
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function bindClient(ClientInterface $client): void
-    {
-        SentrySdk::getGlobalScope()->setClient($client);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function captureMessage(string $message, ?Severity $level = null, ?EventHint $hint = null): ?EventId
-    {
-        return EventCapturer::captureMessage($message, $level, $hint);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function captureException(\Throwable $exception, ?EventHint $hint = null): ?EventId
-    {
-        return EventCapturer::captureException($exception, $hint);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function captureEvent(Event $event, ?EventHint $hint = null): ?EventId
-    {
-        return EventCapturer::captureEvent($event, $hint);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function captureLastError(?EventHint $hint = null): ?EventId
-    {
-        return EventCapturer::captureLastError($hint);
-    }
-
-    /**
-     * {@inheritdoc}
-     *
-     * @param int|float|null $duration
-     */
-    public function captureCheckIn(string $slug, CheckInStatus $status, $duration = null, ?MonitorConfig $monitorConfig = null, ?string $checkInId = null): ?string
-    {
-        return EventCapturer::captureCheckIn($slug, $status, $duration, $monitorConfig, $checkInId);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function addBreadcrumb(Breadcrumb $breadcrumb): bool
-    {
-        $scope = SentrySdk::getIsolationScope();
-
-        return BreadcrumbRecorder::record(SentrySdk::getClient($scope), $scope, $breadcrumb);
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public function addAttachment(Attachment $attachment): bool
-    {
-        if (SentrySdk::getClient() instanceof NoOpClient) {
-            return false;
-        }
-
-        SentrySdk::getIsolationScope()->addAttachment($attachment);
-
-        return true;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function getIntegration(string $className): ?IntegrationInterface
-    {
-        return SentrySdk::getClient()->getIntegration($className);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function startTransaction(TransactionContext $context, array $customSamplingContext = []): Transaction
-    {
-        return TransactionSampler::startTransaction(SentrySdk::getClient()->getOptions(), $context, $customSamplingContext);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function getTransaction(): ?Transaction
-    {
-        return SentrySdk::getIsolationScope()->getTransaction();
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function getSpan(): ?Span
-    {
-        return SentrySdk::getIsolationScope()->getSpan();
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function setSpan(?Span $span): HubInterface
-    {
-        SentrySdk::getIsolationScope()->setSpan($span);
-
-        return $this;
-    }
-
-    /**
-     * @see https://www.php.net/manual/en/language.oop5.cloning.php#object.clone
-     */
-    public function __clone()
-    {
-        throw new \BadMethodCallException('Cloning is forbidden.');
-    }
-
-    /**
-     * @see https://www.php.net/manual/en/language.oop5.magic.php#object.wakeup
-     */
-    public function __wakeup(): void
-    {
-        throw new \BadMethodCallException('Unserializing instances of this class is forbidden.');
-    }
-
-    /**
-     * @see https://www.php.net/manual/en/language.oop5.magic.php#object.sleep
-     */
-    public function __sleep()
-    {
-        throw new \BadMethodCallException('Serializing instances of this class is forbidden.');
-    }
-}
diff --git a/src/State/HubInterface.php b/src/State/HubInterface.php
deleted file mode 100644
index c34ab7e43..000000000
--- a/src/State/HubInterface.php
+++ /dev/null
@@ -1,145 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Sentry\State;
-
-use Sentry\Attachment\Attachment;
-use Sentry\Breadcrumb;
-use Sentry\CheckInStatus;
-use Sentry\ClientInterface;
-use Sentry\Event;
-use Sentry\EventHint;
-use Sentry\EventId;
-use Sentry\Integration\IntegrationInterface;
-use Sentry\MonitorConfig;
-use Sentry\Severity;
-use Sentry\Tracing\Span;
-use Sentry\Tracing\Transaction;
-use Sentry\Tracing\TransactionContext;
-
-interface HubInterface
-{
-    /**
-     * Gets the client bound to the top of the stack.
-     */
-    public function getClient(): ClientInterface;
-
-    /**
-     * Gets the ID of the last captured event.
-     */
-    public function getLastEventId(): ?EventId;
-
-    /**
-     * Creates a new scope with and executes the given operation within. The scope
-     * is automatically removed once the operation finishes or throws.
-     *
-     * @param callable $callback The callback to be executed
-     *
-     * @phpstan-template T
-     *
-     * @phpstan-param callable(Scope): T $callback
-     *
-     * @return mixed|void The callback's return value, upon successful execution
-     *
-     * @phpstan-return T
-     */
-    public function withScope(callable $callback);
-
-    /**
-     * Calls the given callback passing to it the current scope so that any
-     * operation can be run within its context.
-     */
-    public function configureScope(callable $callback): void;
-
-    /**
-     * Binds the given client to the current scope.
-     */
-    public function bindClient(ClientInterface $client): void;
-
-    /**
-     * Captures a message event and sends it to Sentry.
-     */
-    public function captureMessage(string $message, ?Severity $level = null, ?EventHint $hint = null): ?EventId;
-
-    /**
-     * Captures an exception event and sends it to Sentry.
-     */
-    public function captureException(\Throwable $exception, ?EventHint $hint = null): ?EventId;
-
-    /**
-     * Captures a new event using the provided data.
-     */
-    public function captureEvent(Event $event, ?EventHint $hint = null): ?EventId;
-
-    /**
-     * Captures an event that logs the last occurred error.
-     */
-    public function captureLastError(?EventHint $hint = null): ?EventId;
-
-    /**
-     * Records a new breadcrumb which will be attached to future events. They
-     * will be added to subsequent events to provide more context on user's
-     * actions prior to an error or crash.
-     */
-    public function addBreadcrumb(Breadcrumb $breadcrumb): bool;
-
-    /**
-     * Captures a check-in.
-     *
-     * @param int|float|null $duration
-     */
-    public function captureCheckIn(string $slug, CheckInStatus $status, $duration = null, ?MonitorConfig $monitorConfig = null, ?string $checkInId = null): ?string;
-
-    /**
-     * Gets the integration whose FQCN matches the given one if it's available on the current client.
-     *
-     * @param string $className The FQCN of the integration
-     *
-     * @phpstan-template T of IntegrationInterface
-     *
-     * @phpstan-param class-string<T> $className
-     *
-     * @phpstan-return T|null
-     */
-    public function getIntegration(string $className): ?IntegrationInterface;
-
-    /**
-     * Starts a new `Transaction` and returns it. This is the entry point to manual
-     * tracing instrumentation.
-     *
-     * A tree structure can be built by adding child spans to the transaction, and
-     * child spans to other spans. To start a new child span within the transaction
-     * or any span, call the respective `startChild()` method.
-     *
-     * Every child span must be finished before the transaction is finished,
-     * otherwise the unfinished spans are discarded.
-     *
-     * The transaction must be finished with a call to its `finish()` method, at
-     * which point the transaction with all its finished child spans will be sent to
-     * Sentry.
-     *
-     * @param array<string, mixed> $customSamplingContext Additional context that will be passed to the {@see SamplingContext}
-     */
-    public function startTransaction(TransactionContext $context, array $customSamplingContext = []): Transaction;
-
-    /**
-     * Returns the transaction that is on the Hub.
-     */
-    public function getTransaction(): ?Transaction;
-
-    /**
-     * Returns the span that is on the Hub.
-     */
-    public function getSpan(): ?Span;
-
-    /**
-     * Sets the span on the Hub.
-     */
-    public function setSpan(?Span $span): HubInterface;
-
-    /**
-     * Records a new attachment that will be attached to error and transaction events.
-     */
-    public function addAttachment(Attachment $attachment): bool;
-}
diff --git a/src/State/Layer.php b/src/State/Layer.php
deleted file mode 100644
index 3befbd80a..000000000
--- a/src/State/Layer.php
+++ /dev/null
@@ -1,82 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Sentry\State;
-
-use Sentry\ClientInterface;
-
-/**
- * This class holds a pair of client and scope instances for each element in the
- * stack of a {@see Hub}.
- *
- * @internal
- */
-final class Layer
-{
-    /**
-     * @var ClientInterface The client held by this layer
-     */
-    private $client;
-
-    /**
-     * @var Scope The scope held by this layer
-     */
-    private $scope;
-
-    /**
-     * Constructor.
-     *
-     * @param ClientInterface $client The client held by this layer
-     * @param Scope           $scope  The scope held by this layer
-     */
-    public function __construct(ClientInterface $client, Scope $scope)
-    {
-        $this->client = $client;
-        $this->scope = $scope;
-    }
-
-    /**
-     * Gets the client held by this layer.
-     */
-    public function getClient(): ClientInterface
-    {
-        return $this->client;
-    }
-
-    /**
-     * Sets the client held by this layer.
-     *
-     * @param ClientInterface $client The client instance
-     *
-     * @return $this
-     */
-    public function setClient(ClientInterface $client): self
-    {
-        $this->client = $client;
-
-        return $this;
-    }
-
-    /**
-     * Gets the scope held by this layer.
-     */
-    public function getScope(): Scope
-    {
-        return $this->scope;
-    }
-
-    /**
-     * Sets the scope held by this layer.
-     *
-     * @param Scope $scope The scope instance
-     *
-     * @return $this
-     */
-    public function setScope(Scope $scope): self
-    {
-        $this->scope = $scope;
-
-        return $this;
-    }
-}
diff --git a/tests/SentrySdkTest.php b/tests/SentrySdkTest.php
index dcb705292..d72be230f 100644
--- a/tests/SentrySdkTest.php
+++ b/tests/SentrySdkTest.php
@@ -11,7 +11,6 @@
 use Sentry\NoOpClient;
 use Sentry\Options;
 use Sentry\SentrySdk;
-use Sentry\State\Hub;
 use Sentry\Tracing\Span;
 use Sentry\Tracing\SpanContext;
 use Sentry\Tracing\TransactionContext;
@@ -22,32 +21,21 @@
 
 final class SentrySdkTest extends TestCase
 {
-    public function testInit(): void
+    public function testInitResetsRuntimeContext(): void
     {
-        $hub1 = SentrySdk::init();
-        $hub2 = SentrySdk::getCurrentHub();
+        $previousScope = SentrySdk::getIsolationScope();
+        $previousScope->setTag('runtime', 'old');
 
-        $this->assertSame($hub1, $hub2);
-        $this->assertSame(SentrySdk::init(), SentrySdk::init());
-    }
-
-    public function testGetCurrentHub(): void
-    {
         SentrySdk::init();
 
-        $hub2 = SentrySdk::getCurrentHub();
-        $hub3 = SentrySdk::getCurrentHub();
+        $currentScope = SentrySdk::getIsolationScope();
 
-        $this->assertSame($hub2, $hub3);
-    }
+        $this->assertNotSame($previousScope, $currentScope);
 
-    public function testSetCurrentHub(): void
-    {
-        $client = $this->createMock(ClientInterface::class);
-        $hub = new Hub($client);
+        $event = $currentScope->applyToEvent(Event::createEvent());
 
-        $this->assertSame($hub, SentrySdk::setCurrentHub($hub));
-        $this->assertSame($client, SentrySdk::getClient());
+        $this->assertNotNull($event);
+        $this->assertSame([], $event->getTags());
     }
 
     public function testGetGlobalScope(): void
diff --git a/tests/State/HubAdapterTest.php b/tests/State/HubAdapterTest.php
deleted file mode 100644
index 149ba203f..000000000
--- a/tests/State/HubAdapterTest.php
+++ /dev/null
@@ -1,303 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Sentry\Tests\State;
-
-use PHPUnit\Framework\TestCase;
-use Sentry\Breadcrumb;
-use Sentry\CheckInStatus;
-use Sentry\ClientInterface;
-use Sentry\Event;
-use Sentry\EventHint;
-use Sentry\EventId;
-use Sentry\Integration\IntegrationInterface;
-use Sentry\MonitorConfig;
-use Sentry\MonitorSchedule;
-use Sentry\Options;
-use Sentry\SentrySdk;
-use Sentry\Severity;
-use Sentry\State\HubAdapter;
-use Sentry\State\Scope;
-use Sentry\Tracing\Span;
-use Sentry\Tracing\TransactionContext;
-use Sentry\Util\SentryUid;
-
-final class HubAdapterTest extends TestCase
-{
-    public function testGetInstance(): void
-    {
-        $this->assertSame(HubAdapter::getInstance(), HubAdapter::getInstance());
-    }
-
-    public function testGetInstanceReturnsUncloneableInstance(): void
-    {
-        $this->expectException(\BadMethodCallException::class);
-        $this->expectExceptionMessage('Cloning is forbidden.');
-
-        clone HubAdapter::getInstance();
-    }
-
-    public function testHubAdapterThrowsExceptionOnSerialization(): void
-    {
-        $this->expectException(\BadMethodCallException::class);
-        $this->expectExceptionMessage('Serializing instances of this class is forbidden.');
-
-        serialize(HubAdapter::getInstance());
-    }
-
-    public function testHubAdapterThrowsExceptionOnUnserialization(): void
-    {
-        $this->expectException(\BadMethodCallException::class);
-        $this->expectExceptionMessage('Unserializing instances of this class is forbidden.');
-
-        unserialize('O:23:"Sentry\State\HubAdapter":0:{}');
-    }
-
-    public function testGetClient(): void
-    {
-        $client = $this->createMock(ClientInterface::class);
-
-        HubAdapter::getInstance()->bindClient($client);
-
-        $this->assertSame($client, HubAdapter::getInstance()->getClient());
-    }
-
-    public function testGetLastEventId(): void
-    {
-        $event = Event::createEvent();
-
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('captureEvent')
-            ->willReturn($event->getId());
-
-        SentrySdk::getGlobalScope()->setClient($client);
-
-        HubAdapter::getInstance()->captureEvent($event);
-
-        $this->assertSame($event->getId(), HubAdapter::getInstance()->getLastEventId());
-    }
-
-    public function testWithScope(): void
-    {
-        $baseScope = SentrySdk::getIsolationScope();
-
-        $returnValue = HubAdapter::getInstance()->withScope(static function (Scope $scope): string {
-            $scope->setTag('nested', 'yes');
-
-            return 'foobarbaz';
-        });
-
-        $this->assertSame('foobarbaz', $returnValue);
-        $this->assertSame($baseScope, SentrySdk::getIsolationScope());
-
-        $event = $baseScope->applyToEvent(Event::createEvent());
-        $this->assertNotNull($event);
-        $this->assertArrayNotHasKey('nested', $event->getTags());
-    }
-
-    public function testConfigureScope(): void
-    {
-        HubAdapter::getInstance()->configureScope(static function (Scope $scope): void {
-            $scope->setTag('foo', 'bar');
-        });
-
-        $event = SentrySdk::getIsolationScope()->applyToEvent(Event::createEvent());
-
-        $this->assertNotNull($event);
-        $this->assertSame(['foo' => 'bar'], $event->getTags());
-    }
-
-    /**
-     * @dataProvider captureMessageDataProvider
-     */
-    public function testCaptureMessage(array $expectedFunctionCallArgs): void
-    {
-        $eventId = EventId::generate();
-
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('captureMessage')
-            ->with($expectedFunctionCallArgs[0], $expectedFunctionCallArgs[1], $this->isInstanceOf(Scope::class), $expectedFunctionCallArgs[2] ?? null)
-            ->willReturn($eventId);
-
-        SentrySdk::getGlobalScope()->setClient($client);
-
-        $this->assertSame($eventId, HubAdapter::getInstance()->captureMessage(...$expectedFunctionCallArgs));
-    }
-
-    public static function captureMessageDataProvider(): \Generator
-    {
-        yield [['foo', Severity::debug()]];
-        yield [['foo', Severity::debug(), new EventHint()]];
-    }
-
-    /**
-     * @dataProvider captureExceptionDataProvider
-     */
-    public function testCaptureException(array $expectedFunctionCallArgs): void
-    {
-        $eventId = EventId::generate();
-
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('captureException')
-            ->with($expectedFunctionCallArgs[0], $this->isInstanceOf(Scope::class), $expectedFunctionCallArgs[1] ?? null)
-            ->willReturn($eventId);
-
-        SentrySdk::getGlobalScope()->setClient($client);
-
-        $this->assertSame($eventId, HubAdapter::getInstance()->captureException(...$expectedFunctionCallArgs));
-    }
-
-    public static function captureExceptionDataProvider(): \Generator
-    {
-        yield [[new \Exception('foo')]];
-        yield [[new \Exception('foo'), new EventHint()]];
-    }
-
-    public function testCaptureEvent(): void
-    {
-        $event = Event::createEvent();
-        $hint = EventHint::fromArray([]);
-
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('captureEvent')
-            ->with($event, $hint, $this->isInstanceOf(Scope::class))
-            ->willReturn($event->getId());
-
-        SentrySdk::getGlobalScope()->setClient($client);
-
-        $this->assertSame($event->getId(), HubAdapter::getInstance()->captureEvent($event, $hint));
-    }
-
-    /**
-     * @dataProvider captureLastErrorDataProvider
-     */
-    public function testCaptureLastError(array $expectedFunctionCallArgs): void
-    {
-        $eventId = EventId::generate();
-
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('captureLastError')
-            ->with($this->isInstanceOf(Scope::class), $expectedFunctionCallArgs[0] ?? null)
-            ->willReturn($eventId);
-
-        SentrySdk::getGlobalScope()->setClient($client);
-
-        $this->assertSame($eventId, HubAdapter::getInstance()->captureLastError(...$expectedFunctionCallArgs));
-    }
-
-    public static function captureLastErrorDataProvider(): \Generator
-    {
-        yield [[]];
-        yield [[new EventHint()]];
-    }
-
-    public function testCaptureCheckIn(): void
-    {
-        $checkInId = SentryUid::generate();
-
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options([
-                'environment' => Event::DEFAULT_ENVIRONMENT,
-                'release' => '1.1.8',
-            ]));
-        $client->expects($this->once())
-            ->method('captureEvent')
-            ->with($this->callback(static function (Event $event) use ($checkInId): bool {
-                $checkIn = $event->getCheckIn();
-
-                return $checkIn !== null && $checkIn->getId() === $checkInId;
-            }), null, $this->isInstanceOf(Scope::class));
-
-        SentrySdk::getGlobalScope()->setClient($client);
-
-        $this->assertSame($checkInId, HubAdapter::getInstance()->captureCheckIn(
-            'test-crontab',
-            CheckInStatus::ok(),
-            10,
-            new MonitorConfig(
-                MonitorSchedule::crontab('*/5 * * * *'),
-                5,
-                30,
-                'UTC'
-            ),
-            $checkInId
-        ));
-    }
-
-    public function testAddBreadcrumb(): void
-    {
-        $breadcrumb = new Breadcrumb(Breadcrumb::LEVEL_DEBUG, Breadcrumb::TYPE_ERROR, 'user');
-
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options());
-
-        SentrySdk::getGlobalScope()->setClient($client);
-
-        $this->assertTrue(HubAdapter::getInstance()->addBreadcrumb($breadcrumb));
-    }
-
-    public function testGetIntegration(): void
-    {
-        $integration = $this->createMock(IntegrationInterface::class);
-
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getIntegration')
-            ->with(\get_class($integration))
-            ->willReturn($integration);
-
-        SentrySdk::getGlobalScope()->setClient($client);
-
-        $this->assertSame($integration, HubAdapter::getInstance()->getIntegration(\get_class($integration)));
-    }
-
-    public function testStartTransaction(): void
-    {
-        $transactionContext = new TransactionContext('test-transaction');
-
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options());
-
-        SentrySdk::getGlobalScope()->setClient($client);
-
-        $transaction = HubAdapter::getInstance()->startTransaction($transactionContext);
-
-        $this->assertSame('test-transaction', $transaction->getName());
-    }
-
-    public function testGetTransaction(): void
-    {
-        $transaction = HubAdapter::getInstance()->startTransaction(new TransactionContext());
-        SentrySdk::getIsolationScope()->setSpan($transaction);
-
-        $this->assertSame($transaction, HubAdapter::getInstance()->getTransaction());
-    }
-
-    public function testGetSpan(): void
-    {
-        $span = new Span();
-        SentrySdk::getIsolationScope()->setSpan($span);
-
-        $this->assertSame($span, HubAdapter::getInstance()->getSpan());
-    }
-
-    public function testSetSpan(): void
-    {
-        $span = new Span();
-
-        $this->assertSame(HubAdapter::getInstance(), HubAdapter::getInstance()->setSpan($span));
-        $this->assertSame($span, SentrySdk::getIsolationScope()->getSpan());
-    }
-}
diff --git a/tests/State/HubTest.php b/tests/State/HubTest.php
deleted file mode 100644
index 5e9bd9837..000000000
--- a/tests/State/HubTest.php
+++ /dev/null
@@ -1,1055 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Sentry\Tests\State;
-
-use PHPUnit\Framework\MockObject\MockObject;
-use PHPUnit\Framework\TestCase;
-use Sentry\Breadcrumb;
-use Sentry\CheckIn;
-use Sentry\CheckInStatus;
-use Sentry\ClientInterface;
-use Sentry\Event;
-use Sentry\EventHint;
-use Sentry\EventId;
-use Sentry\Integration\IntegrationInterface;
-use Sentry\MonitorConfig;
-use Sentry\MonitorSchedule;
-use Sentry\NoOpClient;
-use Sentry\Options;
-use Sentry\Severity;
-use Sentry\State\Hub;
-use Sentry\State\Scope;
-use Sentry\Tracing\DynamicSamplingContext;
-use Sentry\Tracing\PropagationContext;
-use Sentry\Tracing\SamplingContext;
-use Sentry\Tracing\TransactionContext;
-use Sentry\Tracing\TransactionMetadata;
-use Sentry\Util\SentryUid;
-
-final class HubTest extends TestCase
-{
-    public function testGetClient(): void
-    {
-        /** @var ClientInterface&MockObject $client */
-        $client = $this->createMock(ClientInterface::class);
-        $hub = new Hub($client);
-
-        $this->assertSame($client, $hub->getClient());
-    }
-
-    public function testGetScope(): void
-    {
-        $callbackInvoked = false;
-        $scope = new Scope();
-        $hub = new Hub($this->createMock(ClientInterface::class), $scope);
-
-        $hub->configureScope(function (Scope $scopeArg) use (&$callbackInvoked, $scope) {
-            $this->assertSame($scope, $scopeArg);
-
-            $callbackInvoked = true;
-        });
-
-        $this->assertTrue($callbackInvoked);
-    }
-
-    public function testGetLastEventId(): void
-    {
-        $eventId = EventId::generate();
-
-        /** @var ClientInterface&MockObject $client */
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('captureMessage')
-            ->willReturn($eventId);
-
-        $hub = new Hub($client);
-
-        $this->assertNull($hub->getLastEventId());
-        $this->assertSame($hub->captureMessage('foo'), $hub->getLastEventId());
-        $this->assertSame($eventId, $hub->getLastEventId());
-    }
-
-    public function testPushScope(): void
-    {
-        /** @var ClientInterface&MockObject $client1 */
-        $client1 = $this->createMock(ClientInterface::class);
-        $scope1 = new Scope();
-        $hub = new Hub($client1, $scope1);
-
-        $this->assertSame($client1, $hub->getClient());
-
-        $scope2 = $hub->pushScope();
-
-        $this->assertSame($client1, $hub->getClient());
-        $this->assertNotSame($scope1, $scope2);
-
-        $hub->configureScope(function (Scope $scopeArg) use (&$callbackInvoked, $scope2): void {
-            $this->assertSame($scope2, $scopeArg);
-
-            $callbackInvoked = true;
-        });
-
-        $this->assertTrue($callbackInvoked);
-    }
-
-    public function testPopScope(): void
-    {
-        /** @var ClientInterface&MockObject $client */
-        $client = $this->createMock(ClientInterface::class);
-        $scope1 = new Scope();
-        $hub = new Hub($client, $scope1);
-
-        $this->assertFalse($hub->popScope());
-
-        $scope2 = $hub->pushScope();
-
-        $callbackInvoked = false;
-
-        $hub->configureScope(function (Scope $scopeArg) use ($scope2, &$callbackInvoked): void {
-            $this->assertSame($scope2, $scopeArg);
-
-            $callbackInvoked = true;
-        });
-
-        $this->assertTrue($callbackInvoked);
-        $this->assertSame($client, $hub->getClient());
-
-        $this->assertTrue($hub->popScope());
-
-        $callbackInvoked = false;
-
-        $hub->configureScope(function (Scope $scopeArg) use ($scope1, &$callbackInvoked): void {
-            $this->assertSame($scope1, $scopeArg);
-
-            $callbackInvoked = true;
-        });
-
-        $this->assertTrue($callbackInvoked);
-        $this->assertSame($client, $hub->getClient());
-
-        $this->assertFalse($hub->popScope());
-
-        $callbackInvoked = false;
-
-        $hub->configureScope(function (Scope $scopeArg) use ($scope1, &$callbackInvoked): void {
-            $this->assertSame($scope1, $scopeArg);
-
-            $callbackInvoked = true;
-        });
-
-        $this->assertTrue($callbackInvoked);
-        $this->assertSame($client, $hub->getClient());
-    }
-
-    public function testWithScope(): void
-    {
-        $scope = new Scope();
-        $hub = new Hub(new NoOpClient(), $scope);
-
-        $callbackReturn = $hub->withScope(function (Scope $scopeArg) use ($scope): string {
-            $this->assertNotSame($scope, $scopeArg);
-
-            return 'foobarbaz';
-        });
-
-        $this->assertSame('foobarbaz', $callbackReturn);
-
-        $callbackInvoked = false;
-
-        $hub->configureScope(function (Scope $scopeArg) use (&$callbackInvoked, $scope): void {
-            $this->assertSame($scope, $scopeArg);
-
-            $callbackInvoked = true;
-        });
-
-        $this->assertTrue($callbackInvoked);
-    }
-
-    public function testWithScopeWhenExceptionIsThrown(): void
-    {
-        $scope = new Scope();
-        $hub = new Hub($this->createMock(ClientInterface::class), $scope);
-        $callbackInvoked = false;
-
-        try {
-            $hub->withScope(function (Scope $scopeArg) use ($scope, &$callbackInvoked): void {
-                $this->assertNotSame($scope, $scopeArg);
-
-                $callbackInvoked = true;
-
-                // We throw to test that the scope is correctly popped form the
-                // stack regardless
-                throw new \RuntimeException();
-            });
-        } catch (\RuntimeException $exception) {
-            // Do nothing, we catch this exception to not make the test fail
-        }
-
-        $this->assertTrue($callbackInvoked);
-
-        $callbackInvoked = false;
-
-        $hub->configureScope(function (Scope $scopeArg) use (&$callbackInvoked, $scope): void {
-            $this->assertSame($scope, $scopeArg);
-
-            $callbackInvoked = true;
-        });
-
-        $this->assertTrue($callbackInvoked);
-    }
-
-    public function testConfigureScope(): void
-    {
-        $scope = new Scope();
-        $hub = new Hub(new NoOpClient(), $scope);
-
-        $callbackInvoked = false;
-
-        $hub->configureScope(function (Scope $scopeArg) use ($scope, &$callbackInvoked): void {
-            $this->assertSame($scope, $scopeArg);
-
-            $callbackInvoked = true;
-        });
-
-        $this->assertTrue($callbackInvoked);
-    }
-
-    public function testBindClient(): void
-    {
-        /** @var ClientInterface&MockObject $client1 */
-        $client1 = $this->createMock(ClientInterface::class);
-
-        /** @var ClientInterface&MockObject $client2 */
-        $client2 = $this->createMock(ClientInterface::class);
-
-        $hub = new Hub($client1);
-
-        $this->assertSame($client1, $hub->getClient());
-
-        $hub->bindClient($client2);
-
-        $this->assertSame($client2, $hub->getClient());
-    }
-
-    /**
-     * @dataProvider captureMessageDataProvider
-     */
-    public function testCaptureMessage(array $functionCallArgs, array $expectedFunctionCallArgs, PropagationContext $propagationContext): void
-    {
-        $eventId = EventId::generate();
-        $hub = new Hub(new NoOpClient());
-
-        $hub->configureScope(static function (Scope $scope) use ($propagationContext): void {
-            $scope->setPropagationContext($propagationContext);
-        });
-
-        /** @var ClientInterface&MockObject $client */
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('captureMessage')
-            ->with(...$expectedFunctionCallArgs)
-            ->willReturn($eventId);
-
-        $this->assertNull($hub->captureMessage('foo'));
-
-        $hub->bindClient($client);
-
-        $this->assertSame($eventId, $hub->captureMessage(...$functionCallArgs));
-    }
-
-    public static function captureMessageDataProvider(): \Generator
-    {
-        $propagationContext = PropagationContext::fromDefaults();
-
-        yield [
-            [
-                'foo',
-                Severity::debug(),
-            ],
-            [
-                'foo',
-                Severity::debug(),
-                new Scope($propagationContext),
-            ],
-            $propagationContext,
-        ];
-
-        yield [
-            [
-                'foo',
-                Severity::debug(),
-                new EventHint(),
-            ],
-            [
-                'foo',
-                Severity::debug(),
-                new Scope($propagationContext),
-                new EventHint(),
-            ],
-            $propagationContext,
-        ];
-    }
-
-    /**
-     * @dataProvider captureExceptionDataProvider
-     */
-    public function testCaptureException(array $functionCallArgs, array $expectedFunctionCallArgs, PropagationContext $propagationContext): void
-    {
-        $eventId = EventId::generate();
-        $hub = new Hub(new NoOpClient());
-
-        $hub->configureScope(static function (Scope $scope) use ($propagationContext): void {
-            $scope->setPropagationContext($propagationContext);
-        });
-
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('captureException')
-            ->with(...$expectedFunctionCallArgs)
-            ->willReturn($eventId);
-
-        $this->assertNull($hub->captureException(new \RuntimeException()));
-
-        $hub->bindClient($client);
-
-        $this->assertSame($eventId, $hub->captureException(...$functionCallArgs));
-    }
-
-    public static function captureExceptionDataProvider(): \Generator
-    {
-        $propagationContext = PropagationContext::fromDefaults();
-
-        yield [
-            [
-                new \Exception('foo'),
-            ],
-            [
-                new \Exception('foo'),
-                new Scope($propagationContext),
-                null,
-            ],
-            $propagationContext,
-        ];
-
-        yield [
-            [
-                new \Exception('foo'),
-                new EventHint(),
-            ],
-            [
-                new \Exception('foo'),
-                new Scope($propagationContext),
-                new EventHint(),
-            ],
-            $propagationContext,
-        ];
-    }
-
-    /**
-     * @dataProvider captureLastErrorDataProvider
-     */
-    public function testCaptureLastError(array $functionCallArgs, array $expectedFunctionCallArgs, PropagationContext $propagationContext): void
-    {
-        $eventId = EventId::generate();
-        $hub = new Hub(new NoOpClient());
-
-        $hub->configureScope(static function (Scope $scope) use ($propagationContext): void {
-            $scope->setPropagationContext($propagationContext);
-        });
-
-        /** @var ClientInterface&MockObject $client */
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('captureLastError')
-            ->with(...$expectedFunctionCallArgs)
-            ->willReturn($eventId);
-
-        $this->assertNull($hub->captureLastError(...$functionCallArgs));
-
-        $hub->bindClient($client);
-
-        $this->assertSame($eventId, $hub->captureLastError(...$functionCallArgs));
-    }
-
-    public static function captureLastErrorDataProvider(): \Generator
-    {
-        $propagationContext = PropagationContext::fromDefaults();
-
-        yield [
-            [],
-            [
-                new Scope($propagationContext),
-                null,
-            ],
-            $propagationContext,
-        ];
-
-        yield [
-            [
-                new EventHint(),
-            ],
-            [
-                new Scope($propagationContext),
-                new EventHint(),
-            ],
-            $propagationContext,
-        ];
-    }
-
-    public function testCaptureCheckIn(): void
-    {
-        $expectedCheckIn = new CheckIn(
-            'test-crontab',
-            CheckInStatus::ok(),
-            SentryUid::generate(),
-            '0.0.1-dev',
-            Event::DEFAULT_ENVIRONMENT,
-            10,
-            new MonitorConfig(
-                MonitorSchedule::crontab('*/5 * * * *'),
-                5,
-                30,
-                'UTC'
-            )
-        );
-
-        /** @var ClientInterface&MockObject $client */
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options([
-                'environment' => Event::DEFAULT_ENVIRONMENT,
-                'release' => '0.0.1-dev',
-            ]));
-
-        $client->expects($this->once())
-            ->method('captureEvent')
-            ->with($this->callback(static function (Event $event) use ($expectedCheckIn): bool {
-                return $event->getCheckIn() == $expectedCheckIn;
-            }));
-
-        $hub = new Hub($client);
-
-        $this->assertSame($expectedCheckIn->getId(), $hub->captureCheckIn(
-            $expectedCheckIn->getMonitorSlug(),
-            $expectedCheckIn->getStatus(),
-            $expectedCheckIn->getDuration(),
-            $expectedCheckIn->getMonitorConfig(),
-            $expectedCheckIn->getId()
-        ));
-    }
-
-    public function testCaptureEvent(): void
-    {
-        $hub = new Hub(new NoOpClient());
-        $event = Event::createEvent();
-
-        /** @var ClientInterface&MockObject $client */
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('captureEvent')
-            ->with($event)
-            ->willReturn($event->getId());
-
-        $this->assertNull($hub->captureEvent($event));
-
-        $hub->bindClient($client);
-
-        $this->assertSame($event->getId(), $hub->captureEvent($event));
-    }
-
-    public function testAddBreadcrumb(): void
-    {
-        /** @var ClientInterface&MockObject $client */
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options());
-
-        $callbackInvoked = false;
-        $hub = new Hub(new NoOpClient());
-        $breadcrumb = new Breadcrumb(Breadcrumb::LEVEL_ERROR, Breadcrumb::TYPE_ERROR, 'error_reporting');
-
-        $hub->addBreadcrumb($breadcrumb);
-        $hub->configureScope(function (Scope $scope): void {
-            $event = $scope->applyToEvent(Event::createEvent());
-
-            $this->assertNotNull($event);
-            $this->assertEmpty($event->getBreadcrumbs());
-        });
-
-        $hub->bindClient($client);
-        $hub->addBreadcrumb($breadcrumb);
-        $hub->configureScope(function (Scope $scope) use (&$callbackInvoked, $breadcrumb): void {
-            $event = $scope->applyToEvent(Event::createEvent());
-
-            $this->assertNotNull($event);
-            $this->assertSame([$breadcrumb], $event->getBreadcrumbs());
-
-            $callbackInvoked = true;
-        });
-
-        $this->assertTrue($callbackInvoked);
-    }
-
-    public function testAddBreadcrumbDoesNothingIfMaxBreadcrumbsLimitIsZero(): void
-    {
-        /** @var ClientInterface&MockObject $client */
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options(['max_breadcrumbs' => 0]));
-
-        $hub = new Hub($client);
-
-        $hub->addBreadcrumb(new Breadcrumb(Breadcrumb::LEVEL_ERROR, Breadcrumb::TYPE_ERROR, 'error_reporting'));
-        $hub->configureScope(function (Scope $scope): void {
-            $event = $scope->applyToEvent(Event::createEvent());
-
-            $this->assertNotNull($event);
-            $this->assertEmpty($event->getBreadcrumbs());
-        });
-    }
-
-    public function testAddBreadcrumbRespectsMaxBreadcrumbsLimit(): void
-    {
-        /** @var ClientInterface&MockObject $client */
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->any())
-            ->method('getOptions')
-            ->willReturn(new Options(['max_breadcrumbs' => 2]));
-
-        $hub = new Hub($client);
-        $breadcrumb1 = new Breadcrumb(Breadcrumb::LEVEL_WARNING, Breadcrumb::TYPE_ERROR, 'error_reporting', 'foo');
-        $breadcrumb2 = new Breadcrumb(Breadcrumb::LEVEL_WARNING, Breadcrumb::TYPE_ERROR, 'error_reporting', 'bar');
-        $breadcrumb3 = new Breadcrumb(Breadcrumb::LEVEL_WARNING, Breadcrumb::TYPE_ERROR, 'error_reporting', 'baz');
-
-        $hub->addBreadcrumb($breadcrumb1);
-        $hub->addBreadcrumb($breadcrumb2);
-
-        $hub->configureScope(function (Scope $scope) use ($breadcrumb1, $breadcrumb2): void {
-            $event = $scope->applyToEvent(Event::createEvent());
-
-            $this->assertNotNull($event);
-            $this->assertSame([$breadcrumb1, $breadcrumb2], $event->getBreadcrumbs());
-        });
-
-        $hub->addBreadcrumb($breadcrumb3);
-
-        $hub->configureScope(function (Scope $scope) use ($breadcrumb2, $breadcrumb3): void {
-            $event = $scope->applyToEvent(Event::createEvent());
-
-            $this->assertNotNull($event);
-            $this->assertSame([$breadcrumb2, $breadcrumb3], $event->getBreadcrumbs());
-        });
-    }
-
-    public function testAddBreadcrumbDoesNothingWhenBeforeBreadcrumbCallbackReturnsNull(): void
-    {
-        /** @var ClientInterface&MockObject $client */
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options([
-                'before_breadcrumb' => static function () {
-                    return null;
-                },
-            ]));
-
-        $hub = new Hub($client);
-
-        $hub->addBreadcrumb(new Breadcrumb(Breadcrumb::LEVEL_ERROR, Breadcrumb::TYPE_ERROR, 'error_reporting'));
-        $hub->configureScope(function (Scope $scope): void {
-            $event = $scope->applyToEvent(Event::createEvent());
-
-            $this->assertNotNull($event);
-            $this->assertEmpty($event->getBreadcrumbs());
-        });
-    }
-
-    public function testAddBreadcrumbStoresBreadcrumbReturnedByBeforeBreadcrumbCallback(): void
-    {
-        $callbackInvoked = false;
-        $breadcrumb1 = new Breadcrumb(Breadcrumb::LEVEL_ERROR, Breadcrumb::TYPE_ERROR, 'error_reporting');
-        $breadcrumb2 = new Breadcrumb(Breadcrumb::LEVEL_ERROR, Breadcrumb::TYPE_ERROR, 'error_reporting');
-
-        /** @var ClientInterface&MockObject $client */
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options([
-                'before_breadcrumb' => static function () use ($breadcrumb2): Breadcrumb {
-                    return $breadcrumb2;
-                },
-            ]));
-
-        $hub = new Hub($client);
-
-        $hub->addBreadcrumb($breadcrumb1);
-        $hub->configureScope(function (Scope $scope) use (&$callbackInvoked, $breadcrumb2): void {
-            $event = $scope->applyToEvent(Event::createEvent());
-
-            $this->assertNotNull($event);
-            $this->assertSame([$breadcrumb2], $event->getBreadcrumbs());
-
-            $callbackInvoked = true;
-        });
-
-        $this->assertTrue($callbackInvoked);
-    }
-
-    public function testGetIntegration(): void
-    {
-        /** @var IntegrationInterface&MockObject $integration */
-        $integration = $this->createMock(IntegrationInterface::class);
-
-        /** @var ClientInterface&MockObject $client */
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getIntegration')
-            ->with('Foo\\Bar')
-            ->willReturn($integration);
-
-        $hub = new Hub(new NoOpClient());
-
-        $this->assertNull($hub->getIntegration('Foo\\Bar'));
-
-        $hub->bindClient($client);
-
-        $this->assertSame($integration, $hub->getIntegration('Foo\\Bar'));
-    }
-
-    /**
-     * @dataProvider startTransactionDataProvider
-     */
-    public function testStartTransactionWithTracesSampler(Options $options, TransactionContext $transactionContext, bool $expectedSampled): void
-    {
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn($options);
-
-        $hub = new Hub($client);
-        $transaction = $hub->startTransaction($transactionContext);
-
-        $this->assertSame($expectedSampled, $transaction->getSampled());
-    }
-
-    public function testStartTransactionIgnoresBaggageSampleRateWithoutSentryTrace(): void
-    {
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options([
-                'traces_sample_rate' => 0.0,
-            ]));
-
-        $hub = new Hub($client);
-        $transactionContext = TransactionContext::fromHeaders('', 'sentry-sample_rate=1');
-        $transaction = $hub->startTransaction($transactionContext);
-
-        $this->assertFalse($transaction->getSampled());
-    }
-
-    public static function startTransactionDataProvider(): iterable
-    {
-        yield 'Acceptable float value returned from traces_sampler' => [
-            new Options([
-                'traces_sampler' => static function (): float {
-                    return 1.0;
-                },
-            ]),
-            new TransactionContext(),
-            true,
-        ];
-
-        yield 'Acceptable but too low float value returned from traces_sampler' => [
-            new Options([
-                'traces_sampler' => static function (): float {
-                    return 0.0;
-                },
-            ]),
-            new TransactionContext(),
-            false,
-        ];
-
-        yield 'Acceptable integer value returned from traces_sampler' => [
-            new Options([
-                'traces_sampler' => static function (): int {
-                    return 1;
-                },
-            ]),
-            new TransactionContext(),
-            true,
-        ];
-
-        yield 'Acceptable but too low integer value returned from traces_sampler' => [
-            new Options([
-                'traces_sampler' => static function (): int {
-                    return 0;
-                },
-            ]),
-            new TransactionContext(),
-            false,
-        ];
-
-        yield 'Acceptable float value returned from traces_sample_rate' => [
-            new Options([
-                'traces_sample_rate' => 1.0,
-            ]),
-            new TransactionContext(),
-            true,
-        ];
-
-        yield 'Acceptable but too low float value returned from traces_sample_rate' => [
-            new Options([
-                'traces_sample_rate' => 0.0,
-            ]),
-            new TransactionContext(),
-            false,
-        ];
-
-        yield 'Acceptable integer value returned from traces_sample_rate' => [
-            new Options([
-                'traces_sample_rate' => 1,
-            ]),
-            new TransactionContext(),
-            true,
-        ];
-
-        yield 'Acceptable but too low integer value returned from traces_sample_rate' => [
-            new Options([
-                'traces_sample_rate' => 0,
-            ]),
-            new TransactionContext(),
-            false,
-        ];
-
-        yield 'Acceptable but too low value returned from traces_sample_rate which is preferred over sample_rate' => [
-            new Options([
-                'sample_rate' => 1.0,
-                'traces_sample_rate' => 0.0,
-            ]),
-            new TransactionContext(),
-            false,
-        ];
-
-        yield 'Acceptable value returned from traces_sample_rate which is preferred over sample_rate' => [
-            new Options([
-                'sample_rate' => 0.0,
-                'traces_sample_rate' => 1.0,
-            ]),
-            new TransactionContext(),
-            true,
-        ];
-
-        yield 'Acceptable value returned from SamplingContext::getParentSampled() which is preferred over traces_sample_rate (x1)' => [
-            new Options([
-                'traces_sample_rate' => 0.5,
-            ]),
-            new TransactionContext(TransactionContext::DEFAULT_NAME, true),
-            true,
-        ];
-
-        yield 'Acceptable value returned from SamplingContext::getParentSampled() which is preferred over traces_sample_rate (x2)' => [
-            new Options([
-                'traces_sample_rate' => 1.0,
-            ]),
-            new TransactionContext(TransactionContext::DEFAULT_NAME, false),
-            false,
-        ];
-
-        yield 'Invalid incoming sample_rand is ignored' => [
-            new Options([
-                'traces_sample_rate' => 1.0,
-            ]),
-            TransactionContext::fromHeaders(
-                '566e3688a61d4bc888951642d6f14a19-566e3688a61d4bc8',
-                'sentry-sample_rand=2.0'
-            ),
-            true,
-        ];
-
-        yield 'Out of range sample rate returned from traces_sampler (lower than minimum)' => [
-            new Options([
-                'traces_sampler' => static function (): float {
-                    return -1.0;
-                },
-            ]),
-            new TransactionContext(TransactionContext::DEFAULT_NAME, false),
-            false,
-        ];
-
-        yield 'Out of range sample rate returned from traces_sampler (greater than maximum)' => [
-            new Options([
-                'traces_sampler' => static function (): float {
-                    return 1.1;
-                },
-            ]),
-            new TransactionContext(TransactionContext::DEFAULT_NAME, false),
-            false,
-        ];
-
-        yield 'Invalid type returned from traces_sampler' => [
-            new Options([
-                'traces_sampler' => static function (): string {
-                    return 'foo';
-                },
-            ]),
-            new TransactionContext(TransactionContext::DEFAULT_NAME, false),
-            false,
-        ];
-    }
-
-    public function testStartTransactionDoesNothingIfTracingIsNotEnabled(): void
-    {
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options());
-
-        $hub = new Hub($client);
-        $transaction = $hub->startTransaction(new TransactionContext());
-
-        $this->assertFalse($transaction->getSampled());
-    }
-
-    public function testStartTransactionWithCustomSamplingContext(): void
-    {
-        $customSamplingContext = ['a' => 'b'];
-
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options([
-                'traces_sampler' => function (SamplingContext $samplingContext) use ($customSamplingContext): float {
-                    $this->assertSame($samplingContext->getAdditionalContext(), $customSamplingContext);
-
-                    return 1.0;
-                },
-            ]));
-
-        $hub = new Hub($client);
-        $hub->startTransaction(new TransactionContext(), $customSamplingContext);
-    }
-
-    public function testStartTransactionStartsProfilerWithProfilesSampler(): void
-    {
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options([
-                'traces_sample_rate' => 1.0,
-                'profiles_sampler' => static function (): float {
-                    return 1.0;
-                },
-            ]));
-
-        $hub = new Hub($client);
-        $transaction = $hub->startTransaction(new TransactionContext());
-
-        $this->assertTrue($transaction->getSampled());
-        $this->assertNotNull($transaction->getProfiler());
-    }
-
-    public function testStartTransactionDoesNotStartProfilerWhenProfilesSamplerReturnsZero(): void
-    {
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options([
-                'traces_sample_rate' => 1.0,
-                'profiles_sampler' => static function (): float {
-                    return 0.0;
-                },
-            ]));
-
-        $hub = new Hub($client);
-        $transaction = $hub->startTransaction(new TransactionContext());
-
-        $this->assertTrue($transaction->getSampled());
-        $this->assertNull($transaction->getProfiler());
-    }
-
-    public function testStartTransactionPrefersProfilesSamplerOverProfilesSampleRate(): void
-    {
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options([
-                'traces_sample_rate' => 1.0,
-                'profiles_sample_rate' => 1.0,
-                'profiles_sampler' => static function (): float {
-                    return 0.0;
-                },
-            ]));
-
-        $hub = new Hub($client);
-        $transaction = $hub->startTransaction(new TransactionContext());
-
-        $this->assertTrue($transaction->getSampled());
-        $this->assertNull($transaction->getProfiler());
-    }
-
-    public function testStartTransactionWithProfilesSamplerReceivesCustomSamplingContext(): void
-    {
-        $customSamplingContext = ['a' => 'b'];
-
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options([
-                'traces_sample_rate' => 1.0,
-                'profiles_sampler' => function (SamplingContext $samplingContext) use ($customSamplingContext): float {
-                    $this->assertSame($samplingContext->getAdditionalContext(), $customSamplingContext);
-
-                    return 0.0;
-                },
-            ]));
-
-        $hub = new Hub($client);
-        $hub->startTransaction(new TransactionContext(), $customSamplingContext);
-    }
-
-    public function testStartTransactionDoesNotStartProfilerWhenProfilesSamplerReturnsInvalidValue(): void
-    {
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options([
-                'traces_sample_rate' => 1.0,
-                'profiles_sampler' => static function (): string {
-                    return 'foo';
-                },
-            ]));
-
-        $hub = new Hub($client);
-        $transaction = $hub->startTransaction(new TransactionContext());
-
-        $this->assertTrue($transaction->getSampled());
-        $this->assertNull($transaction->getProfiler());
-    }
-
-    public function testStartTransactionDoesNotCallProfilesSamplerWhenTransactionIsNotSampled(): void
-    {
-        $profilesSamplerInvoked = false;
-
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options([
-                'traces_sample_rate' => 0.0,
-                'profiles_sampler' => static function () use (&$profilesSamplerInvoked): float {
-                    $profilesSamplerInvoked = true;
-
-                    return 1.0;
-                },
-            ]));
-
-        $hub = new Hub($client);
-        $transaction = $hub->startTransaction(new TransactionContext());
-
-        $this->assertFalse($transaction->getSampled());
-        $this->assertFalse($profilesSamplerInvoked);
-        $this->assertNull($transaction->getProfiler());
-    }
-
-    public function testStartTransactionUpdatesTheDscSampleRate(): void
-    {
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options([
-                'traces_sampler' => static function (SamplingContext $samplingContext): float {
-                    return 1.0;
-                },
-            ]));
-
-        $hub = new Hub($client);
-
-        $dsc = DynamicSamplingContext::fromHeader('sentry-trace_id=d49d9bf66f13450b81f65bc51cf49c03,sentry-public_key=public');
-        $transactionMetaData = new TransactionMetadata(null, $dsc);
-        $transactionContext = new TransactionContext(TransactionContext::DEFAULT_NAME, null, $transactionMetaData);
-
-        $transaction = $hub->startTransaction($transactionContext);
-        $this->assertSame('1', $transaction->getMetadata()->getDynamicSamplingContext()->get('sample_rate'));
-    }
-
-    public function testGetTransactionReturnsInstanceSetOnTheScopeIfTransactionIsNotSampled(): void
-    {
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options(['traces_sample_rate' => 1]));
-
-        $hub = new Hub($client);
-        $transaction = $hub->startTransaction(new TransactionContext(TransactionContext::DEFAULT_NAME, false));
-
-        $hub->configureScope(static function (Scope $scope) use ($transaction): void {
-            $scope->setSpan($transaction);
-        });
-
-        $this->assertSame($transaction, $hub->getTransaction());
-    }
-
-    public function testGetTransactionReturnsInstanceSetOnTheScopeIfTransactionIsSampled(): void
-    {
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options(['traces_sample_rate' => 1]));
-
-        $hub = new Hub($client);
-        $transaction = $hub->startTransaction(new TransactionContext(TransactionContext::DEFAULT_NAME, true));
-
-        $hub->configureScope(static function (Scope $scope) use ($transaction): void {
-            $scope->setSpan($transaction);
-        });
-
-        $this->assertSame($transaction, $hub->getTransaction());
-    }
-
-    public function testGetTransactionReturnsNullIfNoTransactionIsSetOnTheScope(): void
-    {
-        $client = $this->createMock(ClientInterface::class);
-        $client->expects($this->once())
-            ->method('getOptions')
-            ->willReturn(new Options(['traces_sample_rate' => 1]));
-
-        $hub = new Hub($client);
-        $hub->startTransaction(new TransactionContext(TransactionContext::DEFAULT_NAME, true));
-
-        $this->assertNull($hub->getTransaction());
-    }
-
-    public function testEventTraceContextIsAlwaysFilled(): void
-    {
-        $hub = new Hub(new NoOpClient());
-
-        $event = Event::createEvent();
-
-        $hub->configureScope(function (Scope $scope) use ($event): void {
-            $event = $scope->applyToEvent($event);
-
-            $this->assertNotEmpty($event->getContexts()['trace']);
-        });
-    }
-
-    public function testEventTraceContextIsNotOverridenWhenPresent(): void
-    {
-        $hub = new Hub(new NoOpClient());
-
-        $traceContext = ['foo' => 'bar'];
-
-        $event = Event::createEvent();
-        $event->setContext('trace', $traceContext);
-
-        $hub->configureScope(function (Scope $scope) use ($event, $traceContext): void {
-            $event = $scope->applyToEvent($event);
-
-            $this->assertEquals($event->getContexts()['trace'], $traceContext);
-        });
-    }
-}
diff --git a/tests/State/LayerTest.php b/tests/State/LayerTest.php
deleted file mode 100644
index 501f0e579..000000000
--- a/tests/State/LayerTest.php
+++ /dev/null
@@ -1,37 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Sentry\Tests\State;
-
-use PHPUnit\Framework\MockObject\MockObject;
-use PHPUnit\Framework\TestCase;
-use Sentry\ClientInterface;
-use Sentry\State\Layer;
-use Sentry\State\Scope;
-
-final class LayerTest extends TestCase
-{
-    public function testGettersAndSetters(): void
-    {
-        /** @var ClientInterface|MockObject $client1 */
-        $client1 = $this->createMock(ClientInterface::class);
-
-        /** @var ClientInterface|MockObject $client2 */
-        $client2 = $this->createMock(ClientInterface::class);
-
-        $scope1 = new Scope();
-        $scope2 = new Scope();
-
-        $layer = new Layer($client1, $scope1);
-
-        $this->assertSame($client1, $layer->getClient());
-        $this->assertSame($scope1, $layer->getScope());
-
-        $layer->setClient($client2);
-        $layer->setScope($scope2);
-
-        $this->assertSame($client2, $layer->getClient());
-        $this->assertSame($scope2, $layer->getScope());
-    }
-}