DataDog · mcculls · Jul 11, 2026 · PerfectSlayer · Jul 15, 2026 · PerfectSlayer
@@ -26,6 +26,7 @@
 import datadog.instrument.utils.ClassLoaderValue;
 import datadog.metrics.api.statsd.StatsDClientManager;
 import datadog.trace.api.Config;
+import datadog.trace.api.InstrumenterConfig;
 import datadog.trace.api.Platform;
 import datadog.trace.api.WithGlobalTracer;
 import datadog.trace.api.appsec.AppSecEventTracker;
@@ -337,6 +338,10 @@ public static void start(
       StaticEventLogger.end("crashtracking");
     }
 
+    if (InstrumenterConfig.get().isLegacyContextManagerEnabled()) {
+      AgentTracer.installLegacyContextManager();
+    }
+
     startDatadogAgent(initTelemetry, inst);
 
     final EnumSet<Library> libraries = detectLibraries(log);

@@ -8,6 +8,8 @@
 import datadog.trace.agent.tooling.MeterInstaller;
 import datadog.trace.agent.tooling.ProfilerInstaller;
 import datadog.trace.agent.tooling.TracerInstaller;
+import datadog.trace.api.InstrumenterConfig;
+import datadog.trace.bootstrap.instrumentation.api.AgentTracer;
 import datadog.trace.bootstrap.instrumentation.api.ProfilingContextIntegration;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -18,6 +20,10 @@ public final class TracerActivation {
 
   public static void activate() {
     try {
+      // Bind legacy context manager (if enabled)
+      if (InstrumenterConfig.get().isLegacyContextManagerEnabled()) {
+        AgentTracer.installLegacyContextManager();
+      }
       // Initialize meter
       MeterInstaller.installMeter();
       // Initialize tracer

@@ -26,6 +26,7 @@ import com.datadog.debugger.sink.DebuggerSink
 import com.datadog.debugger.sink.ProbeStatusSink
 import com.google.common.collect.Sets
 import datadog.communication.ddagent.DDAgentFeaturesDiscovery
+import datadog.context.ContextManager
 import datadog.instrument.classinject.ClassInjector
 import datadog.metrics.agent.AgentMeter
 import datadog.metrics.api.Monitoring
@@ -43,6 +44,7 @@ import datadog.trace.agent.tooling.bytebuddy.matcher.ClassLoaderMatchers
 import datadog.trace.agent.tooling.bytebuddy.matcher.GlobalIgnores
 import datadog.trace.api.Config
 import datadog.trace.api.IdGenerationStrategy
+import datadog.trace.api.InstrumenterConfig
 import datadog.trace.api.Pair
 import datadog.trace.api.ProcessTags
 import datadog.trace.api.TraceConfig
@@ -351,18 +353,22 @@ abstract class InstrumentationSpecification extends DDSpecification implements A
   void setupSpec() {
     InstrumentationErrors.resetErrors()
 
-    AgentMeter.registerIfAbsent(
-    STATS_D_CLIENT,
-    new MonitoringImpl(STATS_D_CLIENT, 10, TimeUnit.SECONDS),
-    DDSketchHistograms.FACTORY
-    )
-
     // If this fails, it's likely the result of another test loading Config before it can be
     // injected into the bootstrap classpath. If one test extends AgentTestRunner in a module, all tests must extend
     assert Config.getClassLoader() == null: "Config must load on the bootstrap classpath."
 
     configurePreAgent()
 
+    if (InstrumenterConfig.get().isLegacyContextManagerEnabled()) {
+      AgentTracer.installLegacyContextManager()
+    }
+
+    AgentMeter.registerIfAbsent(
+    STATS_D_CLIENT,
+    new MonitoringImpl(STATS_D_CLIENT, 10, TimeUnit.SECONDS),
+    DDSketchHistograms.FACTORY
+    )
+
     TEST_DATA_STREAMS_WRITER = new RecordingDatastreamsPayloadWriter()
     DDAgentFeaturesDiscovery features = new MockFeaturesDiscovery(true)
 

@@ -13,8 +13,10 @@
 import datadog.trace.agent.tooling.bytebuddy.matcher.ClassLoaderMatchers;
 import datadog.trace.api.Config;
 import datadog.trace.api.IdGenerationStrategy;
+import datadog.trace.api.InstrumenterConfig;
 import datadog.trace.bootstrap.InstrumentationErrors;
 import datadog.trace.bootstrap.instrumentation.api.AgentSpan;
+import datadog.trace.bootstrap.instrumentation.api.AgentTracer;
 import datadog.trace.bootstrap.instrumentation.api.AgentTracer.TracerAPI;
 import datadog.trace.common.writer.ListWriter;
 import datadog.trace.core.CoreTracer;
@@ -75,6 +77,10 @@ static void initAll() {
     // injected into the bootstrap classpath.
     assertNull(Config.class.getClassLoader(), "Config must load on the bootstrap classpath.");
 
+    if (InstrumenterConfig.get().isLegacyContextManagerEnabled()) {
+      AgentTracer.installLegacyContextManager();
+    }
+
     // Create shared test writer and tracer
     writer = new ListWriter();
     CoreTracer coreTracer =

@@ -38,6 +38,7 @@
 import org.junit.jupiter.api.AfterAll;
 import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 import software.amazon.awssdk.auth.credentials.AnonymousCredentialsProvider;
 import software.amazon.awssdk.core.SdkBytes;
@@ -529,6 +530,7 @@ boolean isDataStreamsEnabled() {
   }
 }
 
+@Disabled("TODO(APMLP-829): non-legacy ContextManager migration still in-progress")
 @WithConfig(key = GeneralConfig.DATA_STREAMS_ENABLED, value = "false")
 @WithConfig(key = TraceInstrumentationConfig.LEGACY_CONTEXT_MANAGER_ENABLED, value = "false")
 class SqsClientV0ContextSwapForkedTest extends SqsClientV0TestBase {}
@@ -756,6 +758,7 @@ class SqsClientV0ReceiveIterationTest extends SqsClientV0ReceiveIterationTestBas
 @WithConfig(key = GeneralConfig.DATA_STREAMS_ENABLED, value = "true")
 class SqsClientV0DataStreamsReceiveIterationTest extends SqsClientV0ReceiveIterationTestBase {}
 
+@Disabled("TODO(APMLP-829): non-legacy ContextManager migration still in-progress")
 @WithConfig(key = GeneralConfig.DATA_STREAMS_ENABLED, value = "false")
 @WithConfig(key = TraceInstrumentationConfig.LEGACY_CONTEXT_MANAGER_ENABLED, value = "false")
 class SqsClientV0ContextSwapReceiveIterationForkedTest extends SqsClientV0ReceiveIterationTestBase {

@@ -32,6 +32,7 @@ import javax.jms.TopicSession
 import jms10mock.Jms10ConnectionFactory
 import org.apache.activemq.command.ActiveMQTextMessage
 import org.apache.activemq.junit.EmbeddedActiveMQBroker
+import spock.lang.Ignore
 import spock.lang.Shared
 
 abstract class JMS1Test extends VersionedNamingTestBase {
@@ -1061,6 +1062,7 @@ class JMS1V0Test extends JMS1Test {
   }
 }
 
+@Ignore("TODO(APMLP-829): non-legacy ContextManager migration still in-progress")
 class JMSContextSwapForkedTest extends JMS1V0Test {
   @Override
   protected void configurePreAgent() {

@@ -42,6 +42,7 @@ import org.springframework.kafka.listener.MessageListener
 import org.springframework.kafka.test.rule.KafkaEmbedded
 import org.springframework.kafka.test.utils.ContainerTestUtils
 import org.springframework.kafka.test.utils.KafkaTestUtils
+import spock.lang.Ignore
 import spock.lang.Shared
 
 import java.util.concurrent.ExecutionException
@@ -1545,6 +1546,7 @@ class KafkaClientDataStreamsDisabledForkedTest extends KafkaClientTestBase {
   }
 }
 
+@Ignore("TODO(APMLP-829): non-legacy ContextManager migration still in-progress")
 class KafkaClientContextSwapForkedTest extends KafkaClientV0ForkedTest {
   void configurePreAgent() {
     super.configurePreAgent()

@@ -48,6 +48,8 @@ import static datadog.trace.agent.test.utils.TraceUtils.runUnderTrace
 import static datadog.trace.bootstrap.instrumentation.api.AgentTracer.activeSpan
 import static datadog.trace.bootstrap.instrumentation.api.AgentTracer.isAsyncPropagationEnabled
 
+import spock.lang.Ignore
+
 abstract class KafkaClientTestBase extends VersionedNamingTestBase {
   static final SHARED_TOPIC = "shared.topic"
 
@@ -1211,6 +1213,7 @@ class KafkaClientDataStreamsDisabledForkedTest extends KafkaClientTestBase {
   }
 }
 
+@Ignore("TODO(APMLP-829): non-legacy ContextManager migration still in-progress")
 class KafkaClientContextSwapForkedTest extends KafkaClientV0ForkedTest {
   void configurePreAgent() {
     super.configurePreAgent()

@@ -107,9 +107,34 @@ public void setup() {
   }
 
   static ContextManager createManager(String type) {
-    return "Continuable".equals(type)
-        ? new ContinuableScopeManager(0, false)
-        : ThreadLocalContextManager.INSTANCE;
+    if ("Continuable".equals(type)) {
+      ContinuableScopeManager csm = new ContinuableScopeManager(0, false);
+      return new ContextManager() {
+        @Override
+        public Context current() {
+          return csm.current();
+        }
+
+        @Override
+        public ContextScope attach(Context ctx) {
+          return csm.attach(ctx);
+        }
+
+        @Override
+        public Context swap(Context ctx) {
+          return csm.swap(ctx);
+        }
+
+        @Override
+        public ContextContinuation capture(Context ctx) {
+          return csm.capture(ctx);
+        }
+
+        @Override
+        public void addListener(ContextListener l) {}
+      };
+    }
+    return ThreadLocalContextManager.INSTANCE;
   }
 
   static Context[] createContexts() {

@@ -22,6 +22,9 @@
 import datadog.communication.ddagent.DDAgentFeaturesDiscovery;
 import datadog.communication.ddagent.ExternalAgentLauncher;
 import datadog.communication.ddagent.SharedCommunicationObjects;
+import datadog.context.Context;
+import datadog.context.ContextContinuation;
+import datadog.context.ContextScope;
 import datadog.context.propagation.Propagators;
 import datadog.environment.ThreadSupport;
 import datadog.logging.RatelimitedLogger;
@@ -2465,4 +2468,24 @@ static TagMap withTracerTags(
     }
     return result.freeze();
   }
+
+  @Override
+  public Context currentContext() {
+    return scopeManager.current();
+  }
+
+  @Override
+  public ContextScope attach(Context context) {
+    return scopeManager.attach(context);
+  }
+
+  @Override
+  public Context swap(Context context) {
+    return scopeManager.swap(context);
+  }
+
+  @Override
+  public ContextContinuation capture(Context context) {
+    return scopeManager.capture(context);
+  }
 }
@@ -14,8 +14,6 @@
 
 import datadog.context.Context;
 import datadog.context.ContextContinuation;
-import datadog.context.ContextListener;
-import datadog.context.ContextManager;
 import datadog.context.ContextScope;
 import datadog.logging.RatelimitedLogger;
 import datadog.trace.api.Config;
@@ -47,7 +45,7 @@
  * from being reported even if all related spans are finished. It also delegates to other
  * ScopeInterceptors to provide additional functionality.
  */
-public final class ContinuableScopeManager implements ContextManager {
+public final class ContinuableScopeManager {
 
   static final Logger log = LoggerFactory.getLogger(ContinuableScopeManager.class);
   static final RatelimitedLogger ratelimitedLog = new RatelimitedLogger(log, 1, MINUTES);
@@ -95,8 +93,6 @@ public ContinuableScopeManager(
     this.profilingContextIntegration = profilingContextIntegration;
     this.profilingEnabled =
         !(profilingContextIntegration instanceof ProfilingContextIntegration.NoOp);
-
-    ContextManager.register(this);
   }
 
   public AgentScope activateSpan(final AgentSpan span) {
@@ -370,18 +366,15 @@ ScopeStack scopeStack() {
     return this.tlsScopeStack.get();
   }
 
-  @Override
   public Context current() {
     final ContinuableScope active = scopeStack().active();
     return active == null ? Context.root() : active.context;
   }
 
-  @Override
   public ContextScope attach(@NonNull Context context) {
     return activate(context);
   }
 
-  @Override
   public Context swap(@NonNull Context context) {
     ScopeStack oldStack = tlsScopeStack.get();
     ContinuableScope oldScope = oldStack.top;
@@ -412,7 +405,6 @@ public Context swap(@NonNull Context context) {
     return new ScopeContext(oldStack);
   }
 
-  @Override
   public ContextContinuation capture(@NonNull Context context) {
     // respect async propagation flag for Context.current().capture()
     ContinuableScope activeScope = scopeStack().active();
@@ -431,12 +423,6 @@ public ContextContinuation capture(@NonNull Context context) {
     return new ScopeContinuation(this, context, CONTEXT, traceCollector).register();
   }
 
-  @Override
-  public void addListener(@NonNull ContextListener unused) {
-    // this new API is not expected to be used in legacy mode...
-    log.warn("Unexpected call to ContextManager.addListener(...)");
-  }
-
   static final class ScopeStackThreadLocal extends ThreadLocal<ScopeStack> {
 
     private final ProfilingContextIntegration profilingContextIntegration;

@@ -2,8 +2,8 @@
 
 import static datadog.trace.bootstrap.instrumentation.api.AgentTracer.noopContinuation;
 import static datadog.trace.bootstrap.instrumentation.api.AgentTracer.noopSpan;
-import static datadog.trace.core.scopemanager.ScopeManagerTest.EVENT.ACTIVATE;
-import static datadog.trace.core.scopemanager.ScopeManagerTest.EVENT.CLOSE;
+import static datadog.trace.core.scopemanager.ScopeManagerForkedTest.EVENT.ACTIVATE;
+import static datadog.trace.core.scopemanager.ScopeManagerForkedTest.EVENT.CLOSE;
 import static datadog.trace.test.util.GCUtils.awaitGC;
 import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 import static org.junit.jupiter.api.Assertions.assertEquals;
@@ -36,6 +36,7 @@
 import datadog.trace.api.scopemanager.ScopeListener;
 import datadog.trace.bootstrap.instrumentation.api.AgentScope;
 import datadog.trace.bootstrap.instrumentation.api.AgentSpan;
+import datadog.trace.bootstrap.instrumentation.api.AgentTracer;
 import datadog.trace.bootstrap.instrumentation.api.ProfilingContextIntegration;
 import datadog.trace.common.writer.ListWriter;
 import datadog.trace.context.TraceScope;
@@ -56,13 +57,14 @@
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReference;
 import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeAll;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.ValueSource;
 import org.tabletest.junit.TableTest;
 
-class ScopeManagerTest extends DDCoreJavaSpecification {
+class ScopeManagerForkedTest extends DDCoreJavaSpecification {
 
   enum EVENT {
     ACTIVATE,
@@ -83,6 +85,11 @@ protected boolean useStrictTraceWrites() {
   ProfilingContextIntegration profilingContext;
   Stateful state;
 
+  @BeforeAll
+  static void installLegacyContextManager() {
+    AgentTracer.installLegacyContextManager();
+  }
+
   @BeforeEach
   void setup() {
     state = mock(Stateful.class);
@@ -91,6 +98,7 @@ void setup() {
     when(profilingContext.name()).thenReturn("mock");
     writer = new ListWriter();
     tracer = tracerBuilder().writer(writer).profilingContextIntegration(profilingContext).build();
+    AgentTracer.forceRegister(tracer);
     scopeManager = ScopeManagerTestBridge.getScopeManager(tracer);
     eventCountingListener = new EventCountingListener();
     scopeManager.addScopeListener(eventCountingListener);

@@ -91,6 +91,7 @@ extra["excludedClassesCoverage"] = listOf(
   "datadog.trace.bootstrap.instrumentation.api.AgentSpan",
   "datadog.trace.bootstrap.instrumentation.api.AgentSpanContext",
   "datadog.trace.bootstrap.instrumentation.api.AgentTracer",
+  "datadog.trace.bootstrap.instrumentation.api.AgentTracer.LegacyContextManager",
   "datadog.trace.bootstrap.instrumentation.api.AgentTracer.NoopAgentHistogram",
   "datadog.trace.bootstrap.instrumentation.api.AgentTracer.NoopAgentTraceCollector",
   "datadog.trace.bootstrap.instrumentation.api.AgentTracer.NoopTraceConfig",