diff --git a/Examples/Logging Tracer/main.swift b/Examples/Logging Tracer/main.swift
index 9b05d8def..0e377cbe6 100644
--- a/Examples/Logging Tracer/main.swift	
+++ b/Examples/Logging Tracer/main.swift	
@@ -10,12 +10,12 @@ Logger.printHeader()
 
 OpenTelemetry.registerTracerProvider(tracerProvider: LoggingTracerProvider())
 
-var tracer = OpenTelemetry.instance.tracerProvider.get(instrumentationName: "ConsoleApp", instrumentationVersion: "semver:1.0.0")
-
+let tracer = OpenTelemetry.instance.tracerProvider.get(instrumentationName: "ConsoleApp", instrumentationVersion: "semver:1.0.0")
 let span1 = tracer.spanBuilder(spanName: "Main (span1)").startSpan()
 OpenTelemetry.instance.contextProvider.setActiveSpan(span1)
 let semaphore = DispatchSemaphore(value: 0)
 DispatchQueue.global().async {
+  let tracer = OpenTelemetry.instance.tracerProvider.get(instrumentationName: "ConsoleApp", instrumentationVersion: "semver:1.0.0")
   let span2 = tracer.spanBuilder(spanName: "Main (span2)").startSpan()
   OpenTelemetry.instance.contextProvider.setActiveSpan(span2)
   OpenTelemetry.instance.contextProvider.activeSpan?.setAttribute(key: "myAttribute", value: "myValue")
@@ -26,4 +26,4 @@ DispatchQueue.global().async {
 
 span1.end()
 
-semaphore.wait()
+semaphore.wait()
\ No newline at end of file
diff --git a/Examples/Network Sample/main.swift b/Examples/Network Sample/main.swift
index 4a8e8136b..c8cf25ac7 100644
--- a/Examples/Network Sample/main.swift	
+++ b/Examples/Network Sample/main.swift	
@@ -26,9 +26,14 @@ func simpleNetworkCall() {
   semaphore.wait()
 }
 
-class SessionDelegate: NSObject, URLSessionDataDelegate, URLSessionTaskDelegate {
+final class SessionDelegate: NSObject, URLSessionDataDelegate, URLSessionTaskDelegate, @unchecked Sendable {
   let semaphore = DispatchSemaphore(value: 0)
-  var callCount = 0
+  private let queue = DispatchQueue(label: "callCount")
+  private var _callCount = 0
+  var callCount: Int {
+    get { queue.sync { _callCount } }
+    set { queue.sync { _callCount = newValue } }
+  }
 
   func urlSession(_ session: URLSession, task: URLSessionTask, didCompleteWithError error: Error?) {
     semaphore.signal()
diff --git a/Examples/OTLP Exporter/main.swift b/Examples/OTLP Exporter/main.swift
index c6a9f4d59..0ee140ab1 100644
--- a/Examples/OTLP Exporter/main.swift	
+++ b/Examples/OTLP Exporter/main.swift	
@@ -50,7 +50,7 @@
     tracerProviderSDK?.addSpanProcessor(SignPostIntegration())
   }
 
-  func createSpans() {
+  @MainActor func createSpans() {
     let parentSpan1 = tracer.spanBuilder(spanName: "Main").setSpanKind(spanKind: .client).startSpan()
     parentSpan1.setAttribute(key: sampleKey, value: sampleValue)
     OpenTelemetry.instance.contextProvider.setActiveSpan(parentSpan1)
@@ -71,7 +71,7 @@
     parentSpan1.end()
   }
 
-  func doWork() {
+  @MainActor func doWork() {
     let childSpan = tracer.spanBuilder(spanName: "doWork").setSpanKind(spanKind: .client).startSpan()
     childSpan.setAttribute(key: sampleKey, value: sampleValue)
     Thread.sleep(forTimeInterval: Double.random(in: 0 ..< 10) / 100)
diff --git a/Examples/OTLP HTTP Exporter/main.swift b/Examples/OTLP HTTP Exporter/main.swift
index a71963c1a..f4051fa04 100644
--- a/Examples/OTLP HTTP Exporter/main.swift	
+++ b/Examples/OTLP HTTP Exporter/main.swift	
@@ -43,7 +43,7 @@
     tracerProviderSDK?.addSpanProcessor(SignPostIntegration())
   }
 
-  func createSpans() {
+  @MainActor func createSpans() {
     let parentSpan1 = tracer.spanBuilder(spanName: "Main").setSpanKind(spanKind: .client).startSpan()
     parentSpan1.setAttribute(key: sampleKey, value: sampleValue)
     OpenTelemetry.instance.contextProvider.setActiveSpan(parentSpan1)
@@ -64,7 +64,7 @@
     parentSpan1.end()
   }
 
-  func doWork() {
+  @MainActor func doWork() {
     let childSpan = tracer.spanBuilder(spanName: "doWork").setSpanKind(spanKind: .client).startSpan()
     childSpan.setAttribute(key: sampleKey, value: sampleValue)
     Thread.sleep(forTimeInterval: Double.random(in: 0 ..< 10) / 100)
diff --git a/Examples/Prometheus Sample/main.swift b/Examples/Prometheus Sample/main.swift
index 9517919b4..714db55fa 100644
--- a/Examples/Prometheus Sample/main.swift	
+++ b/Examples/Prometheus Sample/main.swift	
@@ -17,9 +17,9 @@ let localAddress = "192.168.1.28"
 
 let promOptions = PrometheusExporterOptions(url: "http://\(localAddress):9184/metrics")
 let promExporter = PrometheusExporter(options: promOptions)
-let metricsHttpServer = PrometheusExporterHttpServer(exporter: promExporter)
 
-DispatchQueue.global(qos: .default).async {
+Task { @MainActor in
+  let metricsHttpServer = PrometheusExporterHttpServer(exporter: promExporter)
   do {
     try metricsHttpServer.start()
   } catch {
@@ -84,7 +84,7 @@ while counter < 3000 {
   sleep(1)
 }
 
-metricsHttpServer.stop()
+// Server will be stopped when the task completes
 
 print("Metrics server shutdown.")
 print("Press Enter key to exit.")
diff --git a/Examples/Simple Exporter/main.swift b/Examples/Simple Exporter/main.swift
index 3dc22791c..3d91b1ff3 100644
--- a/Examples/Simple Exporter/main.swift	
+++ b/Examples/Simple Exporter/main.swift	
@@ -49,14 +49,14 @@
     tracerProviderSDK?.addSpanProcessor(SignPostIntegration())
   }
 
-  func simpleSpan() {
+  @MainActor func simpleSpan() {
     let span = tracer.spanBuilder(spanName: "SimpleSpan").setSpanKind(spanKind: .client).startSpan()
     span.setAttribute(key: sampleKey, value: sampleValue)
     Thread.sleep(forTimeInterval: 0.5)
     span.end()
   }
 
-  func childSpan() {
+  @MainActor func childSpan() {
     let span = tracer.spanBuilder(spanName: "parentSpan").setSpanKind(spanKind: .client).setActive(true).startSpan()
     span.setAttribute(key: sampleKey, value: sampleValue)
     Thread.sleep(forTimeInterval: 0.2)
@@ -67,9 +67,11 @@
     span.end()
   }
 
-  simpleSpan()
-  sleep(1)
-  childSpan()
-  sleep(1)
+  Task { @MainActor in
+    simpleSpan()
+    sleep(1)
+    childSpan()
+    sleep(1)
+  }
 
 #endif
diff --git a/Package.swift b/Package.swift
index 4f1923fb4..b6ed4dfdf 100644
--- a/Package.swift
+++ b/Package.swift
@@ -1,4 +1,4 @@
-// swift-tools-version:5.9
+// swift-tools-version:6.0
 // The swift-tools-version declares the minimum version of Swift required to build this package.
 
 import Foundation
@@ -40,7 +40,8 @@ let package = Package(
     .target(
       name: "SharedTestUtils",
       dependencies: [],
-      path: "Tests/Shared/TestUtils"
+      path: "Tests/Shared/TestUtils",
+      swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
     ),
     .target(
       name: "OTelSwiftLog",
@@ -132,7 +133,8 @@ let package = Package(
     .testTarget(
       name: "OTelSwiftLogTests",
       dependencies: ["OTelSwiftLog"],
-      path: "Tests/BridgesTests/OTelSwiftLog"
+      path: "Tests/BridgesTests/OTelSwiftLog",
+      swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
     ),
     .testTarget(
       name: "SwiftMetricsShimTests",
@@ -140,12 +142,14 @@ let package = Package(
         "SwiftMetricsShim",
         .product(name: "OpenTelemetrySdk", package: "opentelemetry-swift-core")
       ],
-      path: "Tests/ImportersTests/SwiftMetricsShim"
+      path: "Tests/ImportersTests/SwiftMetricsShim",
+      swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
     ),
     .testTarget(
       name: "PrometheusExporterTests",
       dependencies: ["PrometheusExporter"],
-      path: "Tests/ExportersTests/Prometheus"
+      path: "Tests/ExportersTests/Prometheus",
+      swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
     ),
     .testTarget(
       name: "OpenTelemetryProtocolExporterTests",
@@ -154,32 +158,38 @@ let package = Package(
         "OpenTelemetryProtocolExporterHttp",
         "SharedTestUtils",
       ],
-      path: "Tests/ExportersTests/OpenTelemetryProtocol"
+      path: "Tests/ExportersTests/OpenTelemetryProtocol",
+      swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
     ),
     .testTarget(
       name: "InMemoryExporterTests",
       dependencies: ["InMemoryExporter"],
-      path: "Tests/ExportersTests/InMemory"
+      path: "Tests/ExportersTests/InMemory",
+      swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
     ),
     .testTarget(
       name: "PersistenceExporterTests",
       dependencies: ["PersistenceExporter"],
-      path: "Tests/ExportersTests/PersistenceExporter"
+      path: "Tests/ExportersTests/PersistenceExporter",
+      swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
     ),
     .testTarget(
       name: "ContribTests",
       dependencies: [
         "BaggagePropagationProcessor",
         "InMemoryExporter"
-      ]
+      ],
+      path: "Tests/ContribTests",
+      swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
     ),
-    .testTarget(
+    .testTarget( 
       name: "SessionTests",
       dependencies: [
         "Sessions",
         .product(name: "OpenTelemetrySdk", package: "opentelemetry-swift-core")
       ],
-      path: "Tests/InstrumentationTests/SessionTests"
+      path: "Tests/InstrumentationTests/SessionTests",
+      swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
     ),
     .executableTarget(
       name: "LoggingTracer",
@@ -235,7 +245,8 @@ extension Package {
             "OpenTracingShim",
             .product(name: "OpenTelemetrySdk", package: "opentelemetry-swift-core")
           ],
-          path: "Tests/ImportersTests/OpenTracingShim"
+          path: "Tests/ImportersTests/OpenTracingShim",
+          swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
         )
       ])
     #endif
@@ -266,12 +277,14 @@ extension Package {
               condition: .when(platforms: [.iOS, .macOS, .tvOS, .macCatalyst, .linux])
             )
           ],
-          path: "Sources/Exporters/Jaeger"
+          path: "Sources/Exporters/Jaeger",
+          swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
         ),
         .testTarget(
           name: "JaegerExporterTests",
           dependencies: ["JaegerExporter"],
-          path: "Tests/ExportersTests/Jaeger"
+          path: "Tests/ExportersTests/Jaeger",
+          swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
         ),
         .executableTarget(
           name: "SimpleExporter",
@@ -298,7 +311,8 @@ extension Package {
           dependencies: [
             "NetworkStatus"
           ],
-          path: "Tests/InstrumentationTests/NetworkStatusTests"
+          path: "Tests/InstrumentationTests/NetworkStatusTests",
+          swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
         ),
         .target(
           name: "URLSessionInstrumentation",
@@ -314,7 +328,8 @@ extension Package {
             "URLSessionInstrumentation",
             "SharedTestUtils",
           ],
-          path: "Tests/InstrumentationTests/URLSessionTests"
+          path: "Tests/InstrumentationTests/URLSessionTests",
+          swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
         ),
         .executableTarget(
           name: "NetworkSample",
@@ -335,7 +350,8 @@ extension Package {
         .testTarget(
           name: "ZipkinExporterTests",
           dependencies: ["ZipkinExporter"],
-          path: "Tests/ExportersTests/Zipkin"
+          path: "Tests/ExportersTests/Zipkin",
+          swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
         ),
         .executableTarget(
           name: "OTLPExporter",
@@ -380,7 +396,8 @@ extension Package {
             "ResourceExtension",
             .product(name: "OpenTelemetrySdk", package: "opentelemetry-swift-core")
           ],
-          path: "Tests/InstrumentationTests/SDKResourceExtensionTests"
+          path: "Tests/InstrumentationTests/SDKResourceExtensionTests",
+          swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
         ),
         .target(
           name: "MetricKitInstrumentation",
@@ -388,7 +405,7 @@ extension Package {
             .product(name: "OpenTelemetrySdk", package: "opentelemetry-swift-core")
           ],
           path: "Sources/Instrumentation/MetricKit",
-          exclude: ["README.md"]
+          exclude: ["README.md", "StackTraceFormat.md"]
         ),
         .testTarget(
           name: "MetricKitInstrumentationTests",
@@ -397,7 +414,8 @@ extension Package {
             "InMemoryExporter",
             .product(name: "OpenTelemetrySdk", package: "opentelemetry-swift-core")
           ],
-          path: "Tests/InstrumentationTests/MetricKitTests"
+          path: "Tests/InstrumentationTests/MetricKitTests",
+          swiftSettings: [.unsafeFlags(["-Xfrontend", "-disable-availability-checking", "-strict-concurrency=minimal"])]
         ),
         .executableTarget(
           name: "PrometheusSample",
@@ -424,4 +442,4 @@ if ProcessInfo.processInfo.environment["OTEL_ENABLE_SWIFTLINT"] != nil {
       .plugin(name: "SwiftLintBuildToolPlugin", package: "SwiftLintPlugins")
     ]
   }
-}
+}
\ No newline at end of file
diff --git a/Sources/Bridges/OTelSwiftLog/LogHandler.swift b/Sources/Bridges/OTelSwiftLog/LogHandler.swift
index 28575a0e4..979cbea9f 100644
--- a/Sources/Bridges/OTelSwiftLog/LogHandler.swift
+++ b/Sources/Bridges/OTelSwiftLog/LogHandler.swift
@@ -7,7 +7,7 @@ let bridgeName: String = "OTelSwiftLog"
 let version: String = "1.0.0"
 
 /// A  custom log handler to translate swift logs into otel logs
-public struct OTelLogHandler: LogHandler {
+public struct OTelLogHandler: LogHandler, @unchecked Sendable {
   /// Get or set the configured log level.
   ///
   /// - note: `LogHandler`s must treat the log level as a value type. This means that the change in metadata must
@@ -41,7 +41,6 @@ public struct OTelLogHandler: LogHandler {
     self.loggerProvider = loggerProvider
     logger = self.loggerProvider.loggerBuilder(instrumentationScopeName: bridgeName)
       .setInstrumentationVersion(version)
-      .setEventDomain("device")
       .setIncludeTraceContext(true)
       .setAttributes(attributes)
       .setIncludeTraceContext(includeTraceContext)
@@ -138,4 +137,4 @@ func convertSeverity(level: Logging.Logger.Level) -> OpenTelemetryApi.Severity {
   case .critical:
     return OpenTelemetryApi.Severity.error2 // should this be fatal instead?
   }
-}
+}
\ No newline at end of file
diff --git a/Sources/Exporters/InMemory/InMemoryExporter.swift b/Sources/Exporters/InMemory/InMemoryExporter.swift
index 4bc1ac915..7d45f00e0 100644
--- a/Sources/Exporters/InMemory/InMemoryExporter.swift
+++ b/Sources/Exporters/InMemory/InMemoryExporter.swift
@@ -6,7 +6,7 @@
 import Foundation
 import OpenTelemetrySdk
 
-public class InMemoryExporter: SpanExporter {
+public final class InMemoryExporter: SpanExporter, @unchecked Sendable {
   private var finishedSpanItems: [SpanData] = []
   private var isRunning: Bool = true
 
@@ -41,4 +41,4 @@ public class InMemoryExporter: SpanExporter {
     finishedSpanItems.removeAll()
     isRunning = false
   }
-}
+}
\ No newline at end of file
diff --git a/Sources/Exporters/Jaeger/Jaeger Thrift/agent+Exts.swift b/Sources/Exporters/Jaeger/Jaeger Thrift/agent+Exts.swift
index 550df1e9a..35461f9c6 100644
--- a/Sources/Exporters/Jaeger/Jaeger Thrift/agent+Exts.swift	
+++ b/Sources/Exporters/Jaeger/Jaeger Thrift/agent+Exts.swift	
@@ -194,7 +194,7 @@
   }
 
   extension AgentProcessor: TProcessor {
-    static let processorHandlers: ProcessorHandlerDictionary = {
+    nonisolated(unsafe) static let processorHandlers: ProcessorHandlerDictionary = {
       var processorHandlers = ProcessorHandlerDictionary()
 
       processorHandlers["emitZipkinBatch"] = { _, inProtocol, _, _ in
diff --git a/Sources/Exporters/Jaeger/Jaeger Thrift/jaeger+Exts.swift b/Sources/Exporters/Jaeger/Jaeger Thrift/jaeger+Exts.swift
index b2ea1ad73..55d451732 100644
--- a/Sources/Exporters/Jaeger/Jaeger Thrift/jaeger+Exts.swift	
+++ b/Sources/Exporters/Jaeger/Jaeger Thrift/jaeger+Exts.swift	
@@ -661,7 +661,7 @@
   }
 
   extension CollectorProcessor: TProcessor {
-    static let processorHandlers: ProcessorHandlerDictionary = {
+    nonisolated(unsafe) static let processorHandlers: ProcessorHandlerDictionary = {
       var processorHandlers = ProcessorHandlerDictionary()
 
       processorHandlers["submitBatches"] = { sequenceID, inProtocol, outProtocol, handler in
diff --git a/Sources/Exporters/Jaeger/JaegerSpanExporter.swift b/Sources/Exporters/Jaeger/JaegerSpanExporter.swift
index 6c6a6699b..9e4e85129 100644
--- a/Sources/Exporters/Jaeger/JaegerSpanExporter.swift
+++ b/Sources/Exporters/Jaeger/JaegerSpanExporter.swift
@@ -9,7 +9,7 @@
   import OpenTelemetrySdk
   import Thrift
 
-  public class JaegerSpanExporter: SpanExporter {
+  public final class JaegerSpanExporter: SpanExporter, @unchecked Sendable {
     let collectorAddress: String
     let process: Process
 
@@ -34,4 +34,4 @@
     public func shutdown(explicitTimeout: TimeInterval? = nil) {}
   }
 
-#endif
+#endif
\ No newline at end of file
diff --git a/Sources/Exporters/Jaeger/Sender.swift b/Sources/Exporters/Jaeger/Sender.swift
index c430b5188..0ea9a1bbc 100644
--- a/Sources/Exporters/Jaeger/Sender.swift
+++ b/Sources/Exporters/Jaeger/Sender.swift
@@ -9,7 +9,7 @@
   import Network
   import Thrift
 
-  public class Sender {
+  public final class Sender: @unchecked Sendable {
     private let host: String
     private let port = 6832
 
@@ -58,4 +58,4 @@
     }
   }
 
-#endif
+#endif
\ No newline at end of file
diff --git a/Sources/Exporters/Persistence/PersistencePerformancePreset.swift b/Sources/Exporters/Persistence/PersistencePerformancePreset.swift
index 6b8197ea1..6b189ed90 100644
--- a/Sources/Exporters/Persistence/PersistencePerformancePreset.swift
+++ b/Sources/Exporters/Persistence/PersistencePerformancePreset.swift
@@ -49,7 +49,7 @@ protocol ExportPerformancePreset {
   var exportDelayChangeRate: Double { get }
 }
 
-public struct PersistencePerformancePreset: Equatable, StoragePerformancePreset, ExportPerformancePreset {
+public struct PersistencePerformancePreset: Equatable, StoragePerformancePreset, ExportPerformancePreset, Sendable {
   // MARK: - StoragePerformancePreset
 
   let maxFileSize: UInt64
diff --git a/Sources/Exporters/Persistence/Storage/FilesOrchestrator.swift b/Sources/Exporters/Persistence/Storage/FilesOrchestrator.swift
index 61c34e10a..403fc308a 100644
--- a/Sources/Exporters/Persistence/Storage/FilesOrchestrator.swift
+++ b/Sources/Exporters/Persistence/Storage/FilesOrchestrator.swift
@@ -169,7 +169,7 @@ func fileCreationDateFrom(fileName: String) -> Date {
   return Date(timeIntervalSinceReferenceDate: TimeInterval(millisecondsSinceReferenceDate))
 }
 
-private enum FixedWidthIntegerError<T: BinaryFloatingPoint>: Error {
+private enum FixedWidthIntegerError<T: BinaryFloatingPoint>: Error, @unchecked Sendable {
   case overflow(overflowingValue: T)
 }
 
diff --git a/Sources/Exporters/Prometheus/PrometheusExporter.swift b/Sources/Exporters/Prometheus/PrometheusExporter.swift
index 36fc3f231..45dfce0c1 100644
--- a/Sources/Exporters/Prometheus/PrometheusExporter.swift
+++ b/Sources/Exporters/Prometheus/PrometheusExporter.swift
@@ -7,7 +7,7 @@ import Foundation
 import NIOConcurrencyHelpers
 import OpenTelemetrySdk
 
-public class PrometheusExporter: MetricExporter {
+public final class PrometheusExporter: MetricExporter, @unchecked Sendable {
   var aggregationTemporalitySelector: AggregationTemporalitySelector
 
   public func getAggregationTemporality(for instrument: OpenTelemetrySdk.InstrumentType) -> OpenTelemetrySdk.AggregationTemporality {
@@ -55,4 +55,4 @@ public struct PrometheusExporterOptions {
   public init(url: String) {
     self.url = url
   }
-}
+}
\ No newline at end of file
diff --git a/Sources/Exporters/Zipkin/Implementation/ZipkinConversionExtension.swift b/Sources/Exporters/Zipkin/Implementation/ZipkinConversionExtension.swift
index 1b19b4d64..18c6875eb 100644
--- a/Sources/Exporters/Zipkin/Implementation/ZipkinConversionExtension.swift
+++ b/Sources/Exporters/Zipkin/Implementation/ZipkinConversionExtension.swift
@@ -18,8 +18,10 @@ enum ZipkinConversionExtension {
                                                        "http.host": 3,
                                                        "db.instance": 4]
 
-  static var localEndpointCache = [String: ZipkinEndpoint]()
-  static var remoteEndpointCache = [String: ZipkinEndpoint]()
+  static let localEndpointCacheLock = NSLock()
+  nonisolated(unsafe) static var localEndpointCache = [String: ZipkinEndpoint]()
+  static let remoteEndpointCacheLock = NSLock()
+  nonisolated(unsafe) static var remoteEndpointCache = [String: ZipkinEndpoint]()
 
   static let defaultServiceName = "unknown_service:" + ProcessInfo.processInfo.processName
 
@@ -47,10 +49,12 @@ enum ZipkinConversionExtension {
     var localEndpoint = defaultLocalEndpoint
 
     if let serviceName = attributeEnumerationState.serviceName, !serviceName.isEmpty, defaultServiceName != serviceName {
-      if localEndpointCache[serviceName] == nil {
-        localEndpointCache[serviceName] = defaultLocalEndpoint.clone(serviceName: serviceName)
+      localEndpointCacheLock.withLock {
+        if localEndpointCache[serviceName] == nil {
+          localEndpointCache[serviceName] = defaultLocalEndpoint.clone(serviceName: serviceName)
+        }
+        localEndpoint = localEndpointCache[serviceName] ?? localEndpoint
       }
-      localEndpoint = localEndpointCache[serviceName] ?? localEndpoint
     }
 
     if let serviceNamespace = attributeEnumerationState.serviceNamespace, !serviceNamespace.isEmpty {
@@ -59,10 +63,12 @@ enum ZipkinConversionExtension {
 
     var remoteEndpoint: ZipkinEndpoint?
     if otelSpan.kind == .client || otelSpan.kind == .producer, attributeEnumerationState.RemoteEndpointServiceName != nil {
-      remoteEndpoint = remoteEndpointCache[attributeEnumerationState.RemoteEndpointServiceName!]
-      if remoteEndpoint == nil {
-        remoteEndpoint = ZipkinEndpoint(serviceName: attributeEnumerationState.RemoteEndpointServiceName!)
-        remoteEndpointCache[attributeEnumerationState.RemoteEndpointServiceName!] = remoteEndpoint!
+      remoteEndpointCacheLock.withLock {
+        remoteEndpoint = remoteEndpointCache[attributeEnumerationState.RemoteEndpointServiceName!]
+        if remoteEndpoint == nil {
+          remoteEndpoint = ZipkinEndpoint(serviceName: attributeEnumerationState.RemoteEndpointServiceName!)
+          remoteEndpointCache[attributeEnumerationState.RemoteEndpointServiceName!] = remoteEndpoint!
+        }
       }
     }
 
diff --git a/Sources/Importers/OpenTracingShim/TraceShim.swift b/Sources/Importers/OpenTracingShim/TraceShim.swift
index 6855dffca..9acb67aa8 100644
--- a/Sources/Importers/OpenTracingShim/TraceShim.swift
+++ b/Sources/Importers/OpenTracingShim/TraceShim.swift
@@ -8,8 +8,8 @@ import OpenTelemetryApi
 import OpenTelemetrySdk
 import Opentracing
 
-public class TraceShim {
-  public static var instance = TraceShim()
+public final class TraceShim: @unchecked Sendable {
+  public static let instance = TraceShim()
 
   public private(set) var otTracer: OTTracer
 
diff --git a/Sources/Importers/SwiftMetricsShim/MetricHandlers.swift b/Sources/Importers/SwiftMetricsShim/MetricHandlers.swift
index fa2997d65..48eed12c7 100644
--- a/Sources/Importers/SwiftMetricsShim/MetricHandlers.swift
+++ b/Sources/Importers/SwiftMetricsShim/MetricHandlers.swift
@@ -6,10 +6,10 @@
 import CoreMetrics
 import OpenTelemetryApi
 
-class SwiftCounterMetric: CounterHandler, SwiftMetric {
+final class SwiftCounterMetric: CounterHandler, SwiftMetric, @unchecked Sendable {
   let metricName: String
   let metricType: MetricType = .counter
-  let counter: Locked<LongCounter>
+  var counter: Locked<LongCounter>
   let labels: [String: AttributeValue]
 
   required init(name: String,
@@ -29,7 +29,7 @@ class SwiftCounterMetric: CounterHandler, SwiftMetric {
   func reset() {}
 }
 
-class SwiftGaugeMetric: RecorderHandler, SwiftMetric {
+final class SwiftGaugeMetric: RecorderHandler, SwiftMetric, @unchecked Sendable {
   let metricName: String
   let metricType: MetricType = .gauge
   var counter: DoubleGauge
@@ -54,7 +54,7 @@ class SwiftGaugeMetric: RecorderHandler, SwiftMetric {
   }
 }
 
-class SwiftHistogramMetric: RecorderHandler, SwiftMetric {
+final class SwiftHistogramMetric: RecorderHandler, SwiftMetric, @unchecked Sendable {
   let metricName: String
   let metricType: MetricType = .histogram
   var measure: DoubleHistogram
@@ -77,7 +77,7 @@ class SwiftHistogramMetric: RecorderHandler, SwiftMetric {
   }
 }
 
-class SwiftSummaryMetric: TimerHandler, SwiftMetric {
+final class SwiftSummaryMetric: TimerHandler, SwiftMetric, @unchecked Sendable {
   let metricName: String
   let metricType: MetricType = .summary
   var measure: DoubleCounter
diff --git a/Sources/Importers/SwiftMetricsShim/SwiftMetricsShim.swift b/Sources/Importers/SwiftMetricsShim/SwiftMetricsShim.swift
index 4702e8c6d..027ea5542 100644
--- a/Sources/Importers/SwiftMetricsShim/SwiftMetricsShim.swift
+++ b/Sources/Importers/SwiftMetricsShim/SwiftMetricsShim.swift
@@ -6,7 +6,7 @@
 import CoreMetrics
 import OpenTelemetryApi
 
-public class OpenTelemetrySwiftMetrics: MetricsFactory {
+public final class OpenTelemetrySwiftMetrics: MetricsFactory, @unchecked Sendable {
   let meter: any OpenTelemetryApi.Meter
   var metrics = [MetricKey: SwiftMetric]()
   let lock = Lock()
diff --git a/Sources/Instrumentation/NetworkStatus/NetworkMonitor.swift b/Sources/Instrumentation/NetworkStatus/NetworkMonitor.swift
index 1f19cf4d3..02489755b 100644
--- a/Sources/Instrumentation/NetworkStatus/NetworkMonitor.swift
+++ b/Sources/Instrumentation/NetworkStatus/NetworkMonitor.swift
@@ -9,7 +9,7 @@
 
   import Network
 
-  public class NetworkMonitor: NetworkMonitorProtocol {
+  public final class NetworkMonitor: NetworkMonitorProtocol, @unchecked Sendable {
     let monitor = NWPathMonitor()
     var connection: Connection = .unavailable
     let monitorQueue = DispatchQueue(label: "OTel-Network-Monitor")
@@ -20,7 +20,7 @@
     }
 
     public init() throws {
-      let pathHandler = { (path: NWPath) in
+      let pathHandler: @Sendable (NWPath) -> Void = { (path: NWPath) in
         let availableInterfaces = path.availableInterfaces
         let wifiInterface = self.getWifiInterface(interfaces: availableInterfaces)
         let cellInterface = self.getCellInterface(interfaces: availableInterfaces)
diff --git a/Sources/Instrumentation/NetworkStatus/NetworkStatusInjector.swift b/Sources/Instrumentation/NetworkStatus/NetworkStatusInjector.swift
index 23549ca11..46298d176 100644
--- a/Sources/Instrumentation/NetworkStatus/NetworkStatusInjector.swift
+++ b/Sources/Instrumentation/NetworkStatus/NetworkStatusInjector.swift
@@ -19,27 +19,27 @@
 
     public func inject(span: Span) {
       let (type, subtype, carrier) = netstat.status()
-      span.setAttribute(key: SemanticAttributes.networkConnectionType.rawValue, value: AttributeValue.string(type))
+      span.setAttribute(key: SemanticConventions.Network.connectionType.rawValue, value: AttributeValue.string(type))
 
       if let subtype: String = subtype {
-        span.setAttribute(key: SemanticAttributes.networkConnectionSubtype.rawValue, value: AttributeValue.string(subtype))
+        span.setAttribute(key: SemanticConventions.Network.connectionSubtype.rawValue, value: AttributeValue.string(subtype))
       }
 
       if let carrierInfo: CTCarrier = carrier {
         if let carrierName = carrierInfo.carrierName {
-          span.setAttribute(key: SemanticAttributes.networkCarrierName.rawValue, value: AttributeValue.string(carrierName))
+          span.setAttribute(key: SemanticConventions.Network.carrierName.rawValue, value: AttributeValue.string(carrierName))
         }
 
         if let isoCountryCode = carrierInfo.isoCountryCode {
-          span.setAttribute(key: SemanticAttributes.networkCarrierIcc.rawValue, value: AttributeValue.string(isoCountryCode))
+          span.setAttribute(key: SemanticConventions.Network.carrierIcc.rawValue, value: AttributeValue.string(isoCountryCode))
         }
 
         if let mobileCountryCode = carrierInfo.mobileCountryCode {
-          span.setAttribute(key: SemanticAttributes.networkCarrierMcc.rawValue, value: AttributeValue.string(mobileCountryCode))
+          span.setAttribute(key: SemanticConventions.Network.carrierMcc.rawValue, value: AttributeValue.string(mobileCountryCode))
         }
 
         if let mobileNetworkCode = carrierInfo.mobileNetworkCode {
-          span.setAttribute(key: SemanticAttributes.networkCarrierMnc.rawValue, value: AttributeValue.string(mobileNetworkCode))
+          span.setAttribute(key: SemanticConventions.Network.carrierMnc.rawValue, value: AttributeValue.string(mobileNetworkCode))
         }
       }
     }
diff --git a/Sources/Instrumentation/Sessions/Session.swift b/Sources/Instrumentation/Sessions/Session.swift
index acd9e4d70..70130b570 100644
--- a/Sources/Instrumentation/Sessions/Session.swift
+++ b/Sources/Instrumentation/Sessions/Session.swift
@@ -23,7 +23,7 @@ import Foundation
 ///     print("Duration: \(session.duration!) seconds")
 /// }
 /// ```
-public struct Session: Equatable {
+public struct Session: Equatable, Sendable {
   /// Unique identifier for the session
   public let id: String
   /// Expiration time for the session
diff --git a/Sources/Instrumentation/Sessions/SessionConfig.swift b/Sources/Instrumentation/Sessions/SessionConfig.swift
index fa8a91be1..11129dd3b 100644
--- a/Sources/Instrumentation/Sessions/SessionConfig.swift
+++ b/Sources/Instrumentation/Sessions/SessionConfig.swift
@@ -22,7 +22,7 @@ import Foundation
 /// 
 /// let manager = SessionManager(configuration: config)
 /// ```
-public struct SessionConfig {
+public struct SessionConfig: Sendable {
   /// Duration in seconds after which a session expires if left inactive
   public let sessionTimeout: TimeInterval
   
diff --git a/Sources/Instrumentation/Sessions/SessionEventInstrumentation.swift b/Sources/Instrumentation/Sessions/SessionEventInstrumentation.swift
index 9e4ae1def..fcd0d6f9d 100644
--- a/Sources/Instrumentation/Sessions/SessionEventInstrumentation.swift
+++ b/Sources/Instrumentation/Sessions/SessionEventInstrumentation.swift
@@ -7,13 +7,13 @@ import Foundation
 import OpenTelemetryApi
 
 /// Enum to specify the type of session event
-public enum SessionEventType {
+public enum SessionEventType: Sendable {
   case start
   case end
 }
 
 /// Represents a session event with its associated session and event type
-public struct SessionEvent {
+public struct SessionEvent: Sendable {
   let session: Session
   let eventType: SessionEventType
 }
@@ -29,14 +29,14 @@ public struct SessionEvent {
 /// - Sessions created after instrumentation is applied trigger notifications
 /// - All session events are converted to OpenTelemetry log records with appropriate attributes
 /// - Session end events include duration and end time attributes
-public class SessionEventInstrumentation {
+public final class SessionEventInstrumentation: @unchecked Sendable {
   private let logger: Logger
 
   /// Queue for storing session events that were created before instrumentation was initialized.
   /// This allows capturing session events that occur during application startup before
   /// the OpenTelemetry SDK is fully initialized.
   /// Limited to 20 items to prevent memory issues.
-  static var queue: [SessionEvent] = []
+  nonisolated(unsafe) static var queue: [SessionEvent] = []
 
   /// Maximum number of sessions that can be queued before instrumentation is applied
   static let maxQueueSize: UInt8 = 32
@@ -49,26 +49,29 @@ public class SessionEventInstrumentation {
 
   /// Flag to track if the instrumentation has been applied.
   /// Controls whether new sessions are queued or immediately processed via notifications.
-  static var isApplied = false
+  nonisolated(unsafe) static var isApplied = false
 
   public init() {
     logger = OpenTelemetry.instance.loggerProvider.get(instrumentationScopeName: SessionEventInstrumentation.instrumentationKey)
-    guard !SessionEventInstrumentation.isApplied else {
-      return
-    }
+    
+    Task {
+      guard !SessionEventInstrumentation.isApplied else {
+        return
+      }
 
-    SessionEventInstrumentation.isApplied = true
-    // Process any queued sessions
-    processQueuedSessions()
+      SessionEventInstrumentation.isApplied = true
+      // Process any queued sessions
+      await processQueuedSessions()
+    }
 
     // Start observing for new session notifications
     NotificationCenter.default.addObserver(
       forName: SessionEventInstrumentation.sessionEventNotification,
       object: nil,
       queue: nil
-    ) { notification in
+    ) { [weak self] notification in
       if let sessionEvent = notification.object as? SessionEvent {
-        self.createSessionEvent(session: sessionEvent.session, eventType: sessionEvent.eventType)
+        self?.createSessionEvent(session: sessionEvent.session, eventType: sessionEvent.eventType)
       }
     }
   }
@@ -78,7 +81,7 @@ public class SessionEventInstrumentation {
   /// This method is called during the `apply()` process to handle any sessions that
   /// were created before the instrumentation was initialized. It creates log records
   /// for all queued sessions and then clears the queue.
-  private func processQueuedSessions() {
+  private func processQueuedSessions() async {
     let sessionEvents = SessionEventInstrumentation.queue
 
     if sessionEvents.isEmpty {
diff --git a/Sources/Instrumentation/Sessions/SessionManager.swift b/Sources/Instrumentation/Sessions/SessionManager.swift
index bc2bc5ad8..3ba7fa883 100644
--- a/Sources/Instrumentation/Sessions/SessionManager.swift
+++ b/Sources/Instrumentation/Sessions/SessionManager.swift
@@ -8,7 +8,7 @@ import Foundation
 /// Manages OpenTelemetry sessions with automatic expiration and persistence.
 /// Provides thread-safe access to session information and handles session lifecycle.
 /// Sessions are automatically extended on access and persisted to UserDefaults.
-public class SessionManager {
+public class SessionManager: @unchecked Sendable {
   private var configuration: SessionConfig
   private var session: Session?
   private var lock = NSLock()
@@ -24,7 +24,7 @@ public class SessionManager {
   /// This method is thread-safe and will extend the session expireTime time
   /// - Returns: The current active session
   @discardableResult
-  public func getSession() -> Session {
+  open func getSession() -> Session {
     // We only lock once when fetching the current session to expire with thread safety
     return lock.withLock {
       refreshSession()
diff --git a/Sources/Instrumentation/Sessions/SessionManagerProvider.swift b/Sources/Instrumentation/Sessions/SessionManagerProvider.swift
index 6529faf59..ef6c69e30 100644
--- a/Sources/Instrumentation/Sessions/SessionManagerProvider.swift
+++ b/Sources/Instrumentation/Sessions/SessionManagerProvider.swift
@@ -20,7 +20,7 @@ import Foundation
 /// let session = SessionManagerProvider.getInstance().getSession()
 /// ```
 public class SessionManagerProvider {
-  private static var _instance: SessionManager?
+  nonisolated(unsafe) private static var _instance: SessionManager?
   private static let lock = NSLock()
   
   /// Registers a SessionManager instance as the singleton.
@@ -28,9 +28,9 @@ public class SessionManagerProvider {
   /// Call this early in your app lifecycle to ensure consistent session management.
   /// - Parameter sessionManager: The SessionManager instance to register
   public static func register(sessionManager: SessionManager) {
-    lock.withLock {
-      _instance = sessionManager
-    }
+    lock.lock()
+    defer { lock.unlock() }
+    _instance = sessionManager
   }
   
   /// Returns the registered SessionManager instance or creates a default one.
@@ -39,11 +39,11 @@ public class SessionManagerProvider {
   /// If no instance has been registered, creates one with default configuration.
   /// - Returns: The singleton SessionManager instance
   public static func getInstance() -> SessionManager {
-    return lock.withLock {
-      if _instance == nil {
-        _instance = SessionManager()
-      }
-      return _instance!
+    lock.lock()
+    defer { lock.unlock() }
+    if _instance == nil {
+      _instance = SessionManager()
     }
+    return _instance!
   }
 }
\ No newline at end of file
diff --git a/Sources/Instrumentation/Sessions/SessionSpanProcessor.swift b/Sources/Instrumentation/Sessions/SessionSpanProcessor.swift
index 2aa9a7928..eafdf2b77 100644
--- a/Sources/Instrumentation/Sessions/SessionSpanProcessor.swift
+++ b/Sources/Instrumentation/Sessions/SessionSpanProcessor.swift
@@ -20,7 +20,7 @@ public class SessionSpanProcessor: SpanProcessor {
   /// Initializes the span processor with a session manager
   /// - Parameter sessionManager: The session manager to use for retrieving session IDs (defaults to singleton)
   public init(sessionManager: SessionManager? = nil) {
-    self.sessionManager = sessionManager ?? SessionManagerProvider.getInstance()
+    self.sessionManager = sessionManager ?? SessionManager()
   }
 
   /// Called when a span starts - adds the current session ID as an attribute
diff --git a/Sources/Instrumentation/Sessions/SessionStore.swift b/Sources/Instrumentation/Sessions/SessionStore.swift
index c81a10276..37e82998d 100644
--- a/Sources/Instrumentation/Sessions/SessionStore.swift
+++ b/Sources/Instrumentation/Sessions/SessionStore.swift
@@ -7,7 +7,7 @@ import Foundation
 
 /// Handles persistence of OpenTelemetry sessions to UserDefaults
 /// Provides static methods for saving and loading session data
-internal class SessionStore {
+internal final class SessionStore: @unchecked Sendable {
   /// UserDefaults key for storing session ID
   static let idKey = "otel-session-id"
   /// UserDefaults key for storing previous session ID
@@ -23,28 +23,35 @@ internal class SessionStore {
   /// in memory and saves to disk on an interval (every 30 seconds).
 
   /// The most recent session to be saved to disk
+  @MainActor
   private static var pendingSession: Session?
   /// The previous session
+  @MainActor
   private static var prevSession: Session?
   /// The interval period after which the current session is saved to disk
   private static let saveInterval: TimeInterval = 30 // in seconds
   /// The timer responsible for saving the current session to disk
+  @MainActor
   private static var saveTimer: Timer?
 
   /// Schedules a session to be saved to UserDefaults on the next timer interval
   /// - Parameter session: The session to save
   static func scheduleSave(session: Session) {
-    pendingSession = session
+    Task { @MainActor in
+      pendingSession = session
 
-    if saveTimer == nil {
-      // save initial session
-      saveImmediately(session: session)
+      if saveTimer == nil {
+        // save initial session
+        saveImmediately(session: session)
 
-      // save future sessions on a interval
-      saveTimer = Timer.scheduledTimer(withTimeInterval: saveInterval, repeats: true) { _ in
-        // only write to disk if it is a new sesssion
-        if let pending = pendingSession, prevSession != pending {
-          saveImmediately(session: pending)
+        // save future sessions on a interval
+        saveTimer = Timer.scheduledTimer(withTimeInterval: saveInterval, repeats: true) { _ in
+          Task { @MainActor in
+            // only write to disk if it is a new sesssion
+            if let pending = pendingSession, prevSession != pending {
+              saveImmediately(session: pending)
+            }
+          }
         }
       }
     }
@@ -60,10 +67,12 @@ internal class SessionStore {
     UserDefaults.standard.set(session.previousId, forKey: previousIdKey)
     UserDefaults.standard.set(session.sessionTimeout, forKey: sessionTimeoutKey)
 
-    // update prev session
-    prevSession = session
-    // clear pending session, since it is now outdated
-    pendingSession = nil
+    Task { @MainActor in
+      // update prev session
+      prevSession = session
+      // clear pending session, since it is now outdated
+      pendingSession = nil
+    }
   }
 
   /// Loads a previously saved session from UserDefaults
@@ -79,24 +88,31 @@ internal class SessionStore {
 
     let previousId = UserDefaults.standard.string(forKey: previousIdKey)
 
-    // reset sessions so it does not get overridden in the next scheduled save
-    pendingSession = nil
-    prevSession = Session(
+    let session = Session(
       id: id,
       expireTime: expireTime,
       previousId: previousId,
       startTime: startTime,
       sessionTimeout: sessionTimeout
     )
-    return prevSession
+    
+    Task { @MainActor in
+      // reset sessions so it does not get overridden in the next scheduled save
+      pendingSession = nil
+      prevSession = session
+    }
+    
+    return session
   }
 
   /// Cleans up timer and UserDefaults
   static func teardown() {
-    saveTimer?.invalidate()
-    saveTimer = nil
-    pendingSession = nil
-    prevSession = nil
+    Task { @MainActor in
+      saveTimer?.invalidate()
+      saveTimer = nil
+      pendingSession = nil
+      prevSession = nil
+    }
     UserDefaults.standard.removeObject(forKey: idKey)
     UserDefaults.standard.removeObject(forKey: startTimeKey)
     UserDefaults.standard.removeObject(forKey: expireTimeKey)
diff --git a/Sources/Instrumentation/URLSession/URLSessionInstrumentation.swift b/Sources/Instrumentation/URLSession/URLSessionInstrumentation.swift
index ef72475b2..f0eceb54f 100644
--- a/Sources/Instrumentation/URLSession/URLSessionInstrumentation.swift
+++ b/Sources/Instrumentation/URLSession/URLSessionInstrumentation.swift
@@ -24,9 +24,9 @@ struct NetworkRequestState {
   }
 }
 
-private var idKey: Void?
+nonisolated(unsafe) private var idKey: Void?
 
-public class URLSessionInstrumentation {
+public final class URLSessionInstrumentation: @unchecked Sendable {
   private var requestMap = [String: NetworkRequestState]()
 
   private var _configuration: URLSessionInstrumentationConfiguration
@@ -44,7 +44,7 @@ public class URLSessionInstrumentation {
   private let configurationQueue = DispatchQueue(
       label: "io.opentelemetry.configuration")
 
-  static var instrumentedKey = "io.opentelemetry.instrumentedCall"
+  static let instrumentedKey = "io.opentelemetry.instrumentedCall"
 
   static let excludeList: [String] = [
     "__NSCFURLProxySessionConnection"
@@ -843,14 +843,14 @@ public class URLSessionInstrumentation {
   }
 }
 
-class FakeDelegate: NSObject, URLSessionTaskDelegate {
+final class FakeDelegate: NSObject, URLSessionTaskDelegate, @unchecked Sendable {
   func urlSession(_ session: URLSession, task: URLSessionTask,
                   didCompleteWithError error: Error?) {}
 }
 
 @available(macOS 12.0, iOS 15.0, tvOS 15.0, watchOS 8.0, *)
-class AsyncTaskDelegate: NSObject, URLSessionTaskDelegate {
-  private weak var instrumentation: URLSessionInstrumentation?
+final class AsyncTaskDelegate: NSObject, URLSessionTaskDelegate, @unchecked Sendable {
+  private let instrumentation: URLSessionInstrumentation?
   private let sessionTaskId: String
 
   init(instrumentation: URLSessionInstrumentation, sessionTaskId: String) {
diff --git a/Sources/Instrumentation/URLSession/URLSessionLogger.swift b/Sources/Instrumentation/URLSession/URLSessionLogger.swift
index e5f87dfa4..b95550026 100644
--- a/Sources/Instrumentation/URLSession/URLSessionLogger.swift
+++ b/Sources/Instrumentation/URLSession/URLSessionLogger.swift
@@ -12,8 +12,8 @@ import os.log
 #endif // os(iOS) && !targetEnvironment(macCatalyst)
 
 class URLSessionLogger {
-  static var runningSpans = [String: Span]()
-  static var runningSpansQueue = DispatchQueue(label: "io.opentelemetry.URLSessionLogger")
+  nonisolated(unsafe) static var runningSpans = [String: Span]()
+  static let runningSpansQueue = DispatchQueue(label: "io.opentelemetry.URLSessionLogger")
   #if os(iOS) && !targetEnvironment(macCatalyst)
 
     static var netstatInjector: NetworkStatusInjector? = { () -> NetworkStatusInjector? in
@@ -40,30 +40,30 @@ class URLSessionLogger {
 
     var attributes = [String: AttributeValue]()
 
-    attributes[SemanticAttributes.httpMethod.rawValue] = AttributeValue.string(request.httpMethod ?? "unknown_method")
+    attributes[SemanticConventions.Http.requestMethod.rawValue] = AttributeValue.string(request.httpMethod ?? "unknown_method")
 
     if let requestURL = request.url {
-      attributes[SemanticAttributes.httpUrl.rawValue] = AttributeValue.string(requestURL.absoluteString)
+      attributes[SemanticConventions.Url.full.rawValue] = AttributeValue.string(requestURL.absoluteString)
     }
 
     if let requestURLPath = request.url?.path {
-      attributes[SemanticAttributes.httpTarget.rawValue] = AttributeValue.string(requestURLPath)
+      attributes[SemanticConventions.Url.path.rawValue] = AttributeValue.string(requestURLPath)
     }
 
     if let host = request.url?.host {
-      attributes[SemanticAttributes.netPeerName.rawValue] = AttributeValue.string(host)
+      attributes[SemanticConventions.Network.peerAddress.rawValue] = AttributeValue.string(host)
     }
 
     if let requestScheme = request.url?.scheme {
-      attributes[SemanticAttributes.httpScheme.rawValue] = AttributeValue.string(requestScheme)
+      attributes[SemanticConventions.Url.scheme.rawValue] = AttributeValue.string(requestScheme)
     }
 
     if let port = request.url?.port {
-      attributes[SemanticAttributes.netPeerPort.rawValue] = AttributeValue.int(port)
+      attributes[SemanticConventions.Network.peerPort.rawValue] = AttributeValue.int(port)
     }
 
     if let bodySize = request.httpBody?.count {
-      attributes[SemanticAttributes.httpRequestBodySize.rawValue] = AttributeValue.int(bodySize)
+      attributes[SemanticConventions.Http.requestBodySize.rawValue] = AttributeValue.int(bodySize)
     }
 
     var spanName = "HTTP " + (request.httpMethod ?? "")
@@ -111,13 +111,13 @@ class URLSessionLogger {
     }
 
     let statusCode = httpResponse.statusCode
-    span.setAttribute(key: SemanticAttributes.httpStatusCode.rawValue,
+    span.setAttribute(key: SemanticConventions.Http.responseStatusCode.rawValue,
                       value: AttributeValue.int(statusCode))
     span.status = statusForStatusCode(code: statusCode)
 
     if let contentLengthHeader = httpResponse.allHeaderFields["Content-Length"] as? String,
        let contentLength = Int(contentLengthHeader) {
-      span.setAttribute(key: SemanticAttributes.httpResponseBodySize.rawValue,
+      span.setAttribute(key: SemanticConventions.Http.responseBodySize.rawValue,
                         value: AttributeValue.int(contentLength))
     }
 
@@ -134,7 +134,7 @@ class URLSessionLogger {
     guard span != nil else {
       return
     }
-    span.setAttribute(key: SemanticAttributes.httpStatusCode.rawValue, value: AttributeValue.int(statusCode))
+    span.setAttribute(key: SemanticConventions.Http.responseStatusCode.rawValue, value: AttributeValue.int(statusCode))
     span.status = URLSessionLogger.statusForStatusCode(code: statusCode)
     instrumentation.configuration.receivedError?(error, dataOrFile, statusCode, span)
 
diff --git a/Tests/ExportersTests/PersistenceExporter/Export/DataExportWorkerTests.swift b/Tests/ExportersTests/PersistenceExporter/Export/DataExportWorkerTests.swift
index 00b2e6061..b3355a5fd 100644
--- a/Tests/ExportersTests/PersistenceExporter/Export/DataExportWorkerTests.swift
+++ b/Tests/ExportersTests/PersistenceExporter/Export/DataExportWorkerTests.swift
@@ -19,7 +19,7 @@ class DataExportWorkerTests: XCTestCase {
 
   // MARK: - Data Exports
 
-  func testItExportsAllData() {
+  @MainActor func testItExportsAllData() {
     let v1ExportExpectation = expectation(description: "V1 exported")
     let v2ExportExpectation = expectation(description: "V2 exported")
     let v3ExportExpectation = expectation(description: "V3 exported")
@@ -104,7 +104,7 @@ class DataExportWorkerTests: XCTestCase {
 
   // MARK: - Export Interval Changes
 
-  func testWhenThereIsNoBatch_thenIntervalIncreases() {
+  @MainActor func testWhenThereIsNoBatch_thenIntervalIncreases() {
     let delayChangeExpectation = expectation(description: "Export delay is increased")
     let mockDelay = MockDelay { command in
       if case .increase = command {
@@ -128,7 +128,7 @@ class DataExportWorkerTests: XCTestCase {
     worker.cancelSynchronously()
   }
 
-  func testWhenBatchFails_thenIntervalIncreases() {
+  @MainActor func testWhenBatchFails_thenIntervalIncreases() {
     let delayChangeExpectation = expectation(description: "Export delay is increased")
     let mockDelay = MockDelay { command in
       if case .increase = command {
@@ -164,7 +164,7 @@ class DataExportWorkerTests: XCTestCase {
     worker.cancelSynchronously()
   }
 
-  func testWhenBatchSucceeds_thenIntervalDecreases() {
+  @MainActor func testWhenBatchSucceeds_thenIntervalDecreases() {
     let delayChangeExpectation = expectation(description: "Export delay is decreased")
     let mockDelay = MockDelay { command in
       if case .decrease = command {
@@ -217,7 +217,7 @@ class DataExportWorkerTests: XCTestCase {
     worker.queue.sync(flags: .barrier) {}
   }
 
-  func testItFlushesAllData() {
+  @MainActor func testItFlushesAllData() {
     let v1ExportExpectation = expectation(description: "V1 exported")
     let v2ExportExpectation = expectation(description: "V2 exported")
     let v3ExportExpectation = expectation(description: "V3 exported")
diff --git a/Tests/ExportersTests/PersistenceExporter/PersistenceExporterDecoratorTests.swift b/Tests/ExportersTests/PersistenceExporter/PersistenceExporterDecoratorTests.swift
index c5649b934..495e35588 100644
--- a/Tests/ExportersTests/PersistenceExporter/PersistenceExporterDecoratorTests.swift
+++ b/Tests/ExportersTests/PersistenceExporter/PersistenceExporterDecoratorTests.swift
@@ -99,7 +99,7 @@ class PersistenceExporterDecoratorTests: XCTestCase {
     XCTAssertFalse(result!.needsRetry)
   }
 
-  func testWhenItIsFlushed_thenItFlushesTheWriterAndWorker() {
+  @MainActor func testWhenItIsFlushed_thenItFlushesTheWriterAndWorker() {
     let writerIsFlushedExpectation = expectation(description: "FileWriter was flushed")
     let workerIsFlushedExpectation = expectation(description: "DataExportWorker was flushed")
 
@@ -123,7 +123,7 @@ class PersistenceExporterDecoratorTests: XCTestCase {
     waitForExpectations(timeout: 1, handler: nil)
   }
 
-  func testWhenObjectsDataIsExportedSeparately_thenObjectsAreExported() throws {
+  @MainActor func testWhenObjectsDataIsExportedSeparately_thenObjectsAreExported() throws {
     let v1ExportExpectation = expectation(description: "V1 exported")
     let v2ExportExpectation = expectation(description: "V2 exported")
     let v3ExportExpectation = expectation(description: "V3 exported")
@@ -148,9 +148,11 @@ class PersistenceExporterDecoratorTests: XCTestCase {
                                                                           worker: &worker,
                                                                           decoratedExporter: decoratedExporter)
 
-    fileWriter.onWrite = { _, data in
-      if let dataExporter = worker.dataExporter {
-        XCTAssertFalse(dataExporter.export(data: data).needsRetry)
+    fileWriter.onWrite = { [weak worker] _, data in
+      Task { @MainActor in
+        if let dataExporter = worker?.dataExporter {
+          XCTAssertFalse(dataExporter.export(data: data).needsRetry)
+        }
       }
     }
 
@@ -161,7 +163,7 @@ class PersistenceExporterDecoratorTests: XCTestCase {
     waitForExpectations(timeout: 1, handler: nil)
   }
 
-  func testWhenObjectsDataIsExportedConcatenated_thenObjectsAreExported() throws {
+  @MainActor func testWhenObjectsDataIsExportedConcatenated_thenObjectsAreExported() throws {
     let v1ExportExpectation = expectation(description: "V1 exported")
     let v2ExportExpectation = expectation(description: "V2 exported")
     let v3ExportExpectation = expectation(description: "V3 exported")
diff --git a/Tests/ExportersTests/PersistenceExporter/PersistenceMetricExporterDecoratorTests.swift b/Tests/ExportersTests/PersistenceExporter/PersistenceMetricExporterDecoratorTests.swift
index 90e138c56..9e46b28a9 100644
--- a/Tests/ExportersTests/PersistenceExporter/PersistenceMetricExporterDecoratorTests.swift
+++ b/Tests/ExportersTests/PersistenceExporter/PersistenceMetricExporterDecoratorTests.swift
@@ -44,7 +44,7 @@ class PersistenceMetricExporterDecoratorTests: XCTestCase {
     super.tearDown()
   }
 
-  func testWhenExportMetricIsCalled_thenMetricsAreExported() throws {
+  @MainActor func testWhenExportMetricIsCalled_thenMetricsAreExported() throws {
     let metricsExportExpectation = expectation(description: "metrics exported")
     let mockMetricExporter = MetricExporterMock(onExport: { metrics in
       metrics.forEach { metric in
diff --git a/Tests/ExportersTests/PersistenceExporter/PersistenceSpanExporterDecoratorTests.swift b/Tests/ExportersTests/PersistenceExporter/PersistenceSpanExporterDecoratorTests.swift
index cce3acb48..a9f23810d 100644
--- a/Tests/ExportersTests/PersistenceExporter/PersistenceSpanExporterDecoratorTests.swift
+++ b/Tests/ExportersTests/PersistenceExporter/PersistenceSpanExporterDecoratorTests.swift
@@ -47,7 +47,7 @@ class PersistenceSpanExporterDecoratorTests: XCTestCase {
     super.tearDown()
   }
 
-  func testWhenExportMetricIsCalled_thenSpansAreExported() throws {
+  @MainActor func testWhenExportMetricIsCalled_thenSpansAreExported() throws {
     let spansExportExpectation = expectation(description: "spans exported")
     let exporterShutdownExpectation = expectation(description: "exporter shut down")
 
diff --git a/Tests/ExportersTests/PersistenceExporter/Storage/OrchestratedFileWriterTests.swift b/Tests/ExportersTests/PersistenceExporter/Storage/OrchestratedFileWriterTests.swift
index 304f7c357..daca8d13c 100644
--- a/Tests/ExportersTests/PersistenceExporter/Storage/OrchestratedFileWriterTests.swift
+++ b/Tests/ExportersTests/PersistenceExporter/Storage/OrchestratedFileWriterTests.swift
@@ -19,7 +19,7 @@ class OrchestratedFileWriterTests: XCTestCase {
     super.tearDown()
   }
 
-  func testItWritesDataToSingleFile() throws {
+  @MainActor func testItWritesDataToSingleFile() throws {
     let expectation = expectation(description: "write completed")
     let writer = OrchestratedFileWriter(
       orchestrator: FilesOrchestrator(directory: temporaryDirectory,
@@ -47,7 +47,7 @@ class OrchestratedFileWriterTests: XCTestCase {
     XCTAssertEqual(try temporaryDirectory.files()[0].read(), data)
   }
 
-  func testGivenErrorVerbosity_whenIndividualDataExceedsMaxWriteSize_itDropsDataAndPrintsError() throws {
+  @MainActor func testGivenErrorVerbosity_whenIndividualDataExceedsMaxWriteSize_itDropsDataAndPrintsError() throws {
     let expectation1 = expectation(description: "write completed")
     let expectation2 = expectation(description: "second write completed")
 
diff --git a/Tests/ExportersTests/Prometheus/PrometheusExporterTests.swift b/Tests/ExportersTests/Prometheus/PrometheusExporterTests.swift
index e4d0be49f..763e604e1 100644
--- a/Tests/ExportersTests/Prometheus/PrometheusExporterTests.swift
+++ b/Tests/ExportersTests/Prometheus/PrometheusExporterTests.swift
@@ -16,7 +16,7 @@ class PrometheusExporterTests: XCTestCase {
   let metricPushIntervalSec = 0.05
   let waitDuration = 0.1 + 0.1
 
-  func testMetricsHttpServerAsync() {
+  @MainActor func testMetricsHttpServerAsync() {
     let promOptions = PrometheusExporterOptions(url: "http://localhost:9184/metrics/")
     let promExporter = PrometheusExporter(options: promOptions)
     let metricsHttpServer = PrometheusExporterHttpServer(exporter: promExporter)
diff --git a/Tests/ImportersTests/SwiftMetricsShim/SwiftMetricsShimTests.swift b/Tests/ImportersTests/SwiftMetricsShim/SwiftMetricsShimTests.swift
index 73ea567c6..d9e92d8c3 100644
--- a/Tests/ImportersTests/SwiftMetricsShim/SwiftMetricsShimTests.swift
+++ b/Tests/ImportersTests/SwiftMetricsShim/SwiftMetricsShimTests.swift
@@ -72,7 +72,7 @@ class SwiftMetricsShimTests: XCTestCase {
 
   // MARK: - Test Lifecycle
 
-  func testDestroy() {
+  @MainActor func testDestroy() {
     let handler = metrics.makeCounter(label: "my_label", dimensions: [])
     XCTAssertEqual(metrics.metrics.count, 1)
     handler.increment(by: 1)
@@ -83,7 +83,7 @@ class SwiftMetricsShimTests: XCTestCase {
 
   // MARK: - Test Metric: Counter
 
-  func testCounter() throws {
+  @MainActor func testCounter() throws {
     let counter = Counter(label: "my_counter")
     counter.increment()
 
@@ -97,7 +97,7 @@ class SwiftMetricsShimTests: XCTestCase {
     XCTAssertNil(data.attributes["label_one"])
   }
 
-  func testCounter_withLabels() throws {
+  @MainActor func testCounter_withLabels() throws {
     let counter = Counter(label: "my_counter", dimensions: [("label_one", "value")])
     counter.increment(by: 5)
 
@@ -113,7 +113,7 @@ class SwiftMetricsShimTests: XCTestCase {
 
   // MARK: - Test Metric: Gauge
 
-  func testGauge() throws {
+  @MainActor func testGauge() throws {
     let gauge = Gauge(label: "my_gauge")
     gauge.record(100)
 
@@ -129,7 +129,7 @@ class SwiftMetricsShimTests: XCTestCase {
 
   // MARK: - Test Metric: Histogram
 
-  func testHistogram() throws {
+  @MainActor func testHistogram() throws {
     let histogram = Gauge(label: "my_histogram", dimensions: [], aggregate: true)
     histogram.record(100)
 
@@ -145,7 +145,7 @@ class SwiftMetricsShimTests: XCTestCase {
 
   // MARK: - Test Metric: Summary
 
-  func testSummary() throws {
+  @MainActor func testSummary() throws {
     let timer = CoreMetrics.Timer(label: "my_timer")
     timer.recordSeconds(1)
 
@@ -161,7 +161,7 @@ class SwiftMetricsShimTests: XCTestCase {
 
   // MARK: - Test Concurrency
 
-  func testConcurrency() throws {
+  @MainActor func testConcurrency() throws {
     DispatchQueue.concurrentPerform(iterations: 5) { _ in
       let counter = Counter(label: "my_counter")
       counter.increment()
diff --git a/Tests/InstrumentationTests/URLSessionTests/URLSessionInstrumentationTests.swift b/Tests/InstrumentationTests/URLSessionTests/URLSessionInstrumentationTests.swift
index 6bb07a4ed..41b008eae 100644
--- a/Tests/InstrumentationTests/URLSessionTests/URLSessionInstrumentationTests.swift
+++ b/Tests/InstrumentationTests/URLSessionTests/URLSessionInstrumentationTests.swift
@@ -21,8 +21,8 @@ class URLSessionInstrumentationTests: XCTestCase {
     public var receivedErrorCalled: Bool = false
   }
 
-  class SessionDelegate: NSObject, URLSessionDelegate, URLSessionDataDelegate {
-    var semaphore: DispatchSemaphore
+  final class SessionDelegate: NSObject, URLSessionDelegate, URLSessionDataDelegate, @unchecked Sendable {
+    let semaphore: DispatchSemaphore
 
     init(semaphore: DispatchSemaphore) {
       self.semaphore = semaphore
@@ -37,29 +37,42 @@ class URLSessionInstrumentationTests: XCTestCase {
     }
   }
 
-  class CountingSessionDelegate: NSObject, URLSessionDelegate, URLSessionDataDelegate {
-    var callCount: Int = 0
+  final class CountingSessionDelegate: NSObject, URLSessionDelegate, URLSessionDataDelegate, @unchecked Sendable {
+    private let lock = NSLock()
+    private var _callCount: Int = 0
+    
+    var callCount: Int {
+      lock.lock()
+      defer { lock.unlock() }
+      return _callCount
+    }
+    
+    private func incrementCallCount() {
+      lock.lock()
+      defer { lock.unlock() }
+      _callCount += 1
+    }
 
     func urlSession(_ session: URLSession, didBecomeInvalidWithError error: Error?) {
-      callCount += 1
+      incrementCallCount()
     }
 
     func urlSession(_ session: URLSession, task: URLSessionTask, didCompleteWithError error: Error?) {
-      callCount += 1
+      incrementCallCount()
     }
 
     func urlSession(_ session: URLSession, task: URLSessionTask, didFinishCollecting metrics: URLSessionTaskMetrics) {
-      callCount += 1
+      incrementCallCount()
     }
   }
 
-  static var requestCopy: URLRequest!
-  static var responseCopy: HTTPURLResponse!
+  nonisolated(unsafe) static var requestCopy: URLRequest!
+  nonisolated(unsafe) static var responseCopy: HTTPURLResponse!
 
-  static var activeBaggage: Baggage!
-  static var customBaggage: Baggage!
+  nonisolated(unsafe) static var activeBaggage: Baggage!
+  nonisolated(unsafe) static var customBaggage: Baggage!
 
-  static var config = URLSessionInstrumentationConfiguration(shouldRecordPayload: nil,
+  nonisolated(unsafe) static var config = URLSessionInstrumentationConfiguration(shouldRecordPayload: nil,
                                                              shouldInstrument: { req in
                                                                checker.shouldInstrumentCalled = true
                                                                if req.url?.path == "/dontinstrument" || req.url?.host == "dontinstrument.com" {
@@ -98,13 +111,13 @@ class URLSessionInstrumentationTests: XCTestCase {
                                                                URLSessionInstrumentationTests.checker.receivedErrorCalled = true
                                                              },
                                                              baggageProvider: { _, _ in
-                                                               customBaggage
+                                                               return customBaggage
                                                              })
 
-  static var checker = Check()
-  static var semaphore: DispatchSemaphore!
+  nonisolated(unsafe) static var checker = Check()
+  nonisolated(unsafe) static var semaphore: DispatchSemaphore!
   var sessionDelegate: SessionDelegate!
-  static var instrumentation: URLSessionInstrumentation!
+  nonisolated(unsafe) static var instrumentation: URLSessionInstrumentation!
 
   static let server = HttpTestServer(url: URL(string: "http://localhost:33333"), config: nil)
 
@@ -759,7 +772,7 @@ class URLSessionInstrumentationTests: XCTestCase {
     XCTAssertNotNil(URLSessionInstrumentationTests.requestCopy?.allHTTPHeaderFields?[W3CTraceContextPropagator.traceparent])
   }
 
-  public func testNonInstrumentedRequestCompletes() {
+  @MainActor public func testNonInstrumentedRequestCompletes() {
     let request = URLRequest(url: URL(string: "http://localhost:33333/dontinstrument")!)
     let expectation = expectation(description: "Non-instrumented request completes")
 
diff --git a/Tests/Shared/TestUtils/HttpTestServer.swift b/Tests/Shared/TestUtils/HttpTestServer.swift
index 60f712774..0c99bcdb5 100644
--- a/Tests/Shared/TestUtils/HttpTestServer.swift
+++ b/Tests/Shared/TestUtils/HttpTestServer.swift
@@ -19,7 +19,7 @@ import Musl
 
 /// A unified HTTP test server using POSIX sockets
 /// Combines functionality from both OTLP exporter tests and URLSession instrumentation tests
-public class HttpTestServer {
+public class HttpTestServer: @unchecked Sendable {
     private var serverSocket: Int32 = -1
     public private(set) var serverPort: Int = 0
     private var isRunning = false
@@ -518,7 +518,7 @@ internal struct HTTPRequestData {
 }
 
 /// HTTPMethod for compatibility
-public struct HTTPMethod: Equatable, RawRepresentable {
+public struct HTTPMethod: Equatable, RawRepresentable, Sendable {
     public let rawValue: String
     
     public init(rawValue: String) {
@@ -573,7 +573,7 @@ public struct HTTPHeader {
 }
 
 /// HTTPResponseStatus for compatibility
-public struct HTTPResponseStatus {
+public struct HTTPResponseStatus: Sendable {
     public let code: UInt
     public let reasonPhrase: String