DataDog · danyal002 · Aug 26, 2026 · Aug 25, 2026
@@ -437,6 +437,7 @@ typedef enum ddog_RemoteConfigProduct {
   DDOG_REMOTE_CONFIG_PRODUCT_FFE_FLAGS,
   DDOG_REMOTE_CONFIG_PRODUCT_LIVE_DEBUGGING,
   DDOG_REMOTE_CONFIG_PRODUCT_LIVE_DEBUGGING_SYMBOL_DB,
+  DDOG_REMOTE_CONFIG_PRODUCT_DEBUG,
 } ddog_RemoteConfigProduct;
 
 typedef enum ddog_SpanProbeTarget {
@@ -1246,6 +1247,8 @@ typedef struct ddog_FfeExposure {
   ddog_CharSlice subject_attributes_json;
   ddog_CharSlice allocation_key;
   ddog_CharSlice variant;
+  int32_t serial_id;
+  bool has_serial_id;
 } ddog_FfeExposure;
 
 typedef struct ddog_Slice_FfeExposure {

@@ -307,6 +307,27 @@ ddog_MaybeError ddog_sidecar_send_trace_v04_bytes(struct ddog_SidecarTransport *
                                                   ddog_CharSlice data,
                                                   const struct ddog_TracerHeaderTags *tracer_header_tags);
 
+/**
+ * Sends a V1-encoded trace to the sidecar via shared memory. The sidecar decodes the V1
+ * `TracerPayload`, can inspect it, and re-encodes it as V1 msgpack on the way to the agent's
+ * `/v1.0/traces` endpoint.
+ */
+ddog_MaybeError ddog_sidecar_send_trace_v1_shm(struct ddog_SidecarTransport **transport,
+                                               const struct ddog_InstanceId *instance_id,
+                                               struct ddog_ShmHandle *shm_handle,
+                                               uintptr_t len,
+                                               const struct ddog_TracerHeaderTags *tracer_header_tags);
+
+/**
+ * Sends a V1-encoded trace as bytes to the sidecar. The sidecar decodes the V1 `TracerPayload`,
+ * can inspect it, and re-encodes it as V1 msgpack on the way to the agent's `/v1.0/traces`
+ * endpoint.
+ */
+ddog_MaybeError ddog_sidecar_send_trace_v1_bytes(struct ddog_SidecarTransport **transport,
+                                                 const struct ddog_InstanceId *instance_id,
+                                                 ddog_CharSlice data,
+                                                 const struct ddog_TracerHeaderTags *tracer_header_tags);
+
 ddog_MaybeError ddog_sidecar_send_debugger_data(struct ddog_SidecarTransport **transport,
                                                 const struct ddog_InstanceId *instance_id,
                                                 ddog_QueueId queue_id,

@@ -31,6 +31,8 @@ typedef struct {
     zend_string *subject_attributes_json;
     zend_string *allocation_key;
     zend_string *variant;
+    int32_t serial_id;
+    bool has_serial_id;
 } dd_ffe_exposure;
 
 static void dd_ffe_release_metric(dd_ffe_metric *metric) {
@@ -168,7 +170,9 @@ void ddtrace_ffe_record_exposure(
     zend_string *targeting_key,
     zend_string *subject_attributes_json,
     zend_string *allocation_key,
-    zend_string *variant
+    zend_string *variant,
+    int32_t serial_id,
+    bool has_serial_id
 ) {
     if (ZSTR_LEN(flag_key) == 0 || ZSTR_LEN(variant) == 0) {
         return;
@@ -200,6 +204,8 @@ void ddtrace_ffe_record_exposure(
     exposure->subject_attributes_json = zend_string_copy(subject_attributes_json);
     exposure->allocation_key = zend_string_copy(allocation_key);
     exposure->variant = zend_string_copy(variant);
+    exposure->serial_id = serial_id;
+    exposure->has_serial_id = has_serial_id;
 }
 
 bool ddtrace_ffe_flush_exposures(void) {
@@ -224,6 +230,8 @@ bool ddtrace_ffe_flush_exposures(void) {
             .subject_attributes_json = dd_zend_string_to_CharSlice(buffer[i].subject_attributes_json),
             .allocation_key = dd_zend_string_to_CharSlice(buffer[i].allocation_key),
             .variant = dd_zend_string_to_CharSlice(buffer[i].variant),
+            .serial_id = buffer[i].serial_id,
+            .has_serial_id = buffer[i].has_serial_id,
         };
     }
 

@@ -3,12 +3,13 @@
 
 #include <stdbool.h>
 #include <stddef.h>
+#include <stdint.h>
 #include <zend.h>
 
 bool ddtrace_ffe_record_evaluation_metric(zend_string *flag_key, zend_string *variant, const char *reason, const char *error_type, zend_string *allocation_key);
 bool ddtrace_ffe_flush_evaluation_metrics(void);
 
-void ddtrace_ffe_record_exposure(zend_string *flag_key, zend_string *targeting_key, zend_string *subject_attributes_json, zend_string *allocation_key, zend_string *variant);
+void ddtrace_ffe_record_exposure(zend_string *flag_key, zend_string *targeting_key, zend_string *subject_attributes_json, zend_string *allocation_key, zend_string *variant, int32_t serial_id, bool has_serial_id);
 bool ddtrace_ffe_flush_exposures(void);
 
 #endif // DDTRACE_FFE_H
@@ -1900,7 +1900,9 @@ PHP_FUNCTION(DDTrace_ffe_evaluate) {
             targeting_key,
             subject_attributes_json,
             allocation_key,
-            variant
+            variant,
+            result.serial_id,
+            result.has_serial_id
         );
         zend_string_release(subject_attributes_json);
     }
+1 −3		.github/CODEOWNERS
+27 −0		.github/workflows/cargo-deny-bans.yml
+2 −2		.github/workflows/pr-metadata-docs-and-deps.yml
+2 −2		.github/workflows/release-proposal-dispatch.yml
+2 −2		.github/workflows/release-proposal-test.yml
+13 −1		.github/workflows/test.yml
+88 −4		Cargo.lock
+1 −0		Cargo.toml
+6 −0		LICENSE-3rdparty.csv
+67 −0		bin_tests/src/modes/behavior.rs
+13 −25		bin_tests/src/modes/unix/test_002_sigchld.rs
+13 −23		bin_tests/src/modes/unix/test_003_sigchld_with_exec.rs
+13 −25		bin_tests/src/modes/unix/test_006_sigchld_sigstack.rs
+2 −2		builder/Cargo.toml
+104 −0		datadog-sidecar-ffi/src/lib.rs
+1 −5		datadog-sidecar/Cargo.toml
+43 −0		datadog-sidecar/src/service/blocking.rs
+1 −0		datadog-sidecar/src/service/ffe_exposures_flusher.rs
+43 −0		datadog-sidecar/src/service/sender.rs
+51 −0		datadog-sidecar/src/service/sidecar_interface.rs
+273 −12		datadog-sidecar/src/service/sidecar_server.rs
+28 −9		datadog-sidecar/src/tracer.rs
+22 −18		docs/RFCs/0015-crashtracker-all-thread-collection.md
+9 −2		libdd-crashtracker/src/receiver/entry_points.rs
+53 −11		libdd-crashtracker/src/receiver/mod.rs
+10 −5		libdd-crashtracker/src/receiver/receive_report.rs
+5 −0		libdd-data-pipeline/Cargo.toml
+5 −1		libdd-data-pipeline/src/trace_exporter/mod.rs
+8 −8		libdd-data-pipeline/src/trace_exporter/trace_serializer.rs
+146 −0		libdd-ffe/src/telemetry/exposures.rs
+6 −1		libdd-profiling/Cargo.toml
+9 −1		libdd-profiling/src/pprof/test_utils.rs
+97 −2		libdd-profiling/src/profiles/compressor.rs
+10 −3		libdd-remote-config/Cargo.toml
+56 −13		libdd-remote-config/src/fetch/agentless.rs
+15 −0		libdd-remote-config/src/fetch/agentless/integration_tests.rs
+1 −1		libdd-remote-config/src/fetch/fetcher.rs
+16 −0		libdd-remote-config/src/fetch/mod.rs
+4 −3		libdd-remote-config/src/fetch/multitarget.rs
+2 −2		libdd-remote-config/src/fetch/shared.rs
+4 −4		libdd-remote-config/src/fetch/single.rs
+21 −12		libdd-sampling/benches/sampling_bench.rs
+23 −14		libdd-sampling/src/v04_span.rs
+55 −39		libdd-trace-stats/src/span_concentrator/aggregation.rs
+28 −27		libdd-trace-stats/src/span_concentrator/tests.rs
+16 −12		libdd-trace-stats/src/stats_exporter.rs
+5 −1		libdd-trace-utils/Cargo.toml
+42 −2		libdd-trace-utils/benches/deserialization.rs
+20 −14		libdd-trace-utils/src/change_buffer/mod.rs
+8 −4		libdd-trace-utils/src/msgpack_encoder/v04/mod.rs
+91 −6		libdd-trace-utils/src/send_with_retry/compression.rs
+18 −8		libdd-trace-utils/src/span/mod.rs
+27 −18		libdd-trace-utils/src/span/v04/mod.rs
+20 −0		tests/wasm/Cargo.toml
+110 −0		tests/wasm/tests/compression.rs