diff --git a/embrace-android-sdk/src/main/java/io/embrace/android/embracesdk/capture/envelope/session/SessionPayloadSourceImpl.kt b/embrace-android-sdk/src/main/java/io/embrace/android/embracesdk/capture/envelope/session/SessionPayloadSourceImpl.kt
index 10be94e20..a775a83aa 100644
--- a/embrace-android-sdk/src/main/java/io/embrace/android/embracesdk/capture/envelope/session/SessionPayloadSourceImpl.kt
+++ b/embrace-android-sdk/src/main/java/io/embrace/android/embracesdk/capture/envelope/session/SessionPayloadSourceImpl.kt
@@ -1,7 +1,13 @@
 package io.embrace.android.embracesdk.capture.envelope.session
 
 import io.embrace.android.embracesdk.anr.ndk.NativeThreadSamplerService
+import io.embrace.android.embracesdk.arch.schema.AppTerminationCause
 import io.embrace.android.embracesdk.internal.payload.SessionPayload
+import io.embrace.android.embracesdk.internal.payload.Span
+import io.embrace.android.embracesdk.internal.payload.toNewPayload
+import io.embrace.android.embracesdk.internal.spans.CurrentSessionSpan
+import io.embrace.android.embracesdk.internal.spans.EmbraceSpanData
+import io.embrace.android.embracesdk.internal.spans.SpanSink
 import io.embrace.android.embracesdk.logging.InternalErrorService
 import io.embrace.android.embracesdk.session.captureDataSafely
 import io.embrace.android.embracesdk.session.orchestrator.SessionSnapshotType
@@ -9,12 +15,24 @@ import io.embrace.android.embracesdk.session.orchestrator.SessionSnapshotType
 internal class SessionPayloadSourceImpl(
     private val internalErrorService: InternalErrorService,
     private val nativeThreadSamplerService: NativeThreadSamplerService?,
+    private val spanSink: SpanSink,
+    private val currentSessionSpan: CurrentSessionSpan
 ) : SessionPayloadSource {
 
-    override fun getSessionPayload(endType: SessionSnapshotType) = SessionPayload(
-        spans = null,
-        spanSnapshots = null,
-        internalError = captureDataSafely { internalErrorService.currentExceptionError?.toNewPayload() },
-        sharedLibSymbolMapping = captureDataSafely { nativeThreadSamplerService?.getNativeSymbols() }
-    )
+    override fun getSessionPayload(endType: SessionSnapshotType): SessionPayload {
+        return SessionPayload(
+            spans = retrieveSpanData(endType),
+            spanSnapshots = null,
+            internalError = captureDataSafely { internalErrorService.currentExceptionError?.toNewPayload() },
+            sharedLibSymbolMapping = captureDataSafely { nativeThreadSamplerService?.getNativeSymbols() }
+        )
+    }
+
+    private fun retrieveSpanData(endType: SessionSnapshotType): List<Span>? = captureDataSafely {
+        when (endType) {
+            SessionSnapshotType.NORMAL_END -> currentSessionSpan.endSession(null)
+            SessionSnapshotType.PERIODIC_CACHE -> spanSink.completedSpans()
+            SessionSnapshotType.JVM_CRASH -> currentSessionSpan.endSession(AppTerminationCause.Crash)
+        }.map(EmbraceSpanData::toNewPayload)
+    }
 }
diff --git a/embrace-android-sdk/src/main/java/io/embrace/android/embracesdk/internal/payload/SpanMapper.kt b/embrace-android-sdk/src/main/java/io/embrace/android/embracesdk/internal/payload/SpanMapper.kt
index 42f05b720..144e841c2 100644
--- a/embrace-android-sdk/src/main/java/io/embrace/android/embracesdk/internal/payload/SpanMapper.kt
+++ b/embrace-android-sdk/src/main/java/io/embrace/android/embracesdk/internal/payload/SpanMapper.kt
@@ -1,32 +1,31 @@
 package io.embrace.android.embracesdk.internal.payload
 
-import io.opentelemetry.api.common.Attributes
+import io.embrace.android.embracesdk.internal.spans.EmbraceSpanData
+import io.embrace.android.embracesdk.spans.EmbraceSpanEvent
 import io.opentelemetry.api.trace.StatusCode
-import io.opentelemetry.sdk.trace.data.EventData
-import io.opentelemetry.sdk.trace.data.SpanData
 
-internal fun SpanData.toNewPayload() = Span(
+internal fun EmbraceSpanData.toNewPayload() = Span(
     traceId = traceId,
     spanId = spanId,
     parentSpanId = parentSpanId,
     name = name,
-    startTimeUnixNano = startEpochNanos,
-    endTimeUnixNano = endEpochNanos,
-    status = when (status.statusCode) {
+    startTimeUnixNano = startTimeNanos,
+    endTimeUnixNano = endTimeNanos,
+    status = when (status) {
         StatusCode.UNSET -> Span.Status.UNSET
         StatusCode.OK -> Span.Status.OK
         StatusCode.ERROR -> Span.Status.ERROR
         else -> Span.Status.UNSET
     },
-    events = events.map(EventData::toNewPayload),
+    events = events.map(EmbraceSpanEvent::toNewPayload),
     attributes = attributes.toNewPayload()
 )
 
-internal fun EventData.toNewPayload() = SpanEvent(
+internal fun EmbraceSpanEvent.toNewPayload() = SpanEvent(
     name = name,
-    timeUnixNano = epochNanos,
+    timeUnixNano = timestampNanos,
     attributes = attributes.toNewPayload()
 )
 
-internal fun Attributes.toNewPayload(): List<Attribute> =
-    asMap().map { (key, value) -> Attribute(key.key, value.toString()) }
+internal fun Map<String, String>.toNewPayload(): List<Attribute> =
+    map { (key, value) -> Attribute(key, value) }
diff --git a/embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/capture/envelope/SessionEnvelopeSourceTest.kt b/embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/capture/envelope/SessionEnvelopeSourceTest.kt
index 930d6466e..995788b27 100644
--- a/embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/capture/envelope/SessionEnvelopeSourceTest.kt
+++ b/embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/capture/envelope/SessionEnvelopeSourceTest.kt
@@ -1,8 +1,10 @@
 package io.embrace.android.embracesdk.capture.envelope
 
 import io.embrace.android.embracesdk.capture.envelope.session.SessionPayloadSourceImpl
+import io.embrace.android.embracesdk.fakes.FakeCurrentSessionSpan
 import io.embrace.android.embracesdk.fakes.FakeInternalErrorService
 import io.embrace.android.embracesdk.fakes.FakeNativeThreadSamplerService
+import io.embrace.android.embracesdk.internal.spans.SpanSinkImpl
 import io.embrace.android.embracesdk.session.orchestrator.SessionSnapshotType
 import org.junit.Test
 
@@ -13,7 +15,9 @@ internal class SessionEnvelopeSourceTest {
         SessionEnvelopeSource(
             SessionPayloadSourceImpl(
                 FakeInternalErrorService(),
-                FakeNativeThreadSamplerService()
+                FakeNativeThreadSamplerService(),
+                SpanSinkImpl(),
+                FakeCurrentSessionSpan()
             )
         ).getEnvelope(SessionSnapshotType.NORMAL_END)
     }
diff --git a/embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/capture/envelope/session/SessionPayloadSourceImplTest.kt b/embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/capture/envelope/session/SessionPayloadSourceImplTest.kt
index c3ad2c53b..71422798e 100644
--- a/embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/capture/envelope/session/SessionPayloadSourceImplTest.kt
+++ b/embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/capture/envelope/session/SessionPayloadSourceImplTest.kt
@@ -1,18 +1,26 @@
 package io.embrace.android.embracesdk.capture.envelope.session
 
 import io.embrace.android.embracesdk.fakes.FakeClock
+import io.embrace.android.embracesdk.fakes.FakeCurrentSessionSpan
 import io.embrace.android.embracesdk.fakes.FakeInternalErrorService
 import io.embrace.android.embracesdk.fakes.FakeNativeThreadSamplerService
+import io.embrace.android.embracesdk.fakes.FakeSpanData
 import io.embrace.android.embracesdk.internal.payload.SessionPayload
+import io.embrace.android.embracesdk.internal.spans.EmbraceSpanData
+import io.embrace.android.embracesdk.internal.spans.SpanSinkImpl
 import io.embrace.android.embracesdk.payload.LegacyExceptionError
 import io.embrace.android.embracesdk.session.orchestrator.SessionSnapshotType
 import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNull
 import org.junit.Before
 import org.junit.Test
 
 internal class SessionPayloadSourceImplTest {
 
     private lateinit var impl: SessionPayloadSourceImpl
+    private lateinit var sink: SpanSinkImpl
+    private lateinit var currentSessionSpan: FakeCurrentSessionSpan
+    private val cacheSpan = FakeSpanData(name = "cache-span")
 
     @Before
     fun setUp() {
@@ -21,9 +29,17 @@ internal class SessionPayloadSourceImplTest {
                 addException(RuntimeException(), "test", FakeClock())
             }
         }
+        sink = SpanSinkImpl().apply {
+            storeCompletedSpans(listOf(cacheSpan))
+        }
+        currentSessionSpan = FakeCurrentSessionSpan().apply {
+            spanData = listOf(EmbraceSpanData(FakeSpanData("my-span")))
+        }
         impl = SessionPayloadSourceImpl(
             errorService,
-            FakeNativeThreadSamplerService()
+            FakeNativeThreadSamplerService(),
+            sink,
+            currentSessionSpan
         )
     }
 
@@ -31,23 +47,30 @@ internal class SessionPayloadSourceImplTest {
     fun `session crash`() {
         val payload = impl.getSessionPayload(SessionSnapshotType.JVM_CRASH)
         assertPayloadPopulated(payload)
+        val span = checkNotNull(payload.spans?.single())
+        assertEquals("my-span", span.name)
     }
 
     @Test
     fun `session cache`() {
         val payload = impl.getSessionPayload(SessionSnapshotType.PERIODIC_CACHE)
         assertPayloadPopulated(payload)
+        val span = checkNotNull(payload.spans?.single())
+        assertEquals("cache-span", span.name)
     }
 
     @Test
     fun `session lifecycle change`() {
         val payload = impl.getSessionPayload(SessionSnapshotType.NORMAL_END)
         assertPayloadPopulated(payload)
+        val span = checkNotNull(payload.spans?.single())
+        assertEquals("my-span", span.name)
     }
 
     private fun assertPayloadPopulated(payload: SessionPayload) {
         val err = checkNotNull(payload.internalError)
         assertEquals(1, err.count)
         assertEquals(mapOf("armeabi-v7a" to "my-symbols"), payload.sharedLibSymbolMapping)
+        assertNull(payload.spanSnapshots)
     }
 }
diff --git a/embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/fakes/FakeCurrentSessionSpan.kt b/embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/fakes/FakeCurrentSessionSpan.kt
index 98739a5fc..a87ef46a5 100644
--- a/embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/fakes/FakeCurrentSessionSpan.kt
+++ b/embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/fakes/FakeCurrentSessionSpan.kt
@@ -12,6 +12,7 @@ internal class FakeCurrentSessionSpan : CurrentSessionSpan {
     var initializedCallCount = 0
     var addedEvents = mutableListOf<SpanEventData>()
     var addedAttributes = mutableListOf<SpanAttributeData>()
+    var spanData = listOf<EmbraceSpanData>()
 
     override fun initializeService(sdkInitStartTimeMs: Long) {
     }
@@ -32,7 +33,7 @@ internal class FakeCurrentSessionSpan : CurrentSessionSpan {
     }
 
     override fun endSession(appTerminationCause: AppTerminationCause?): List<EmbraceSpanData> {
-        return emptyList()
+        return spanData
     }
 
     override fun canStartNewSpan(parent: EmbraceSpan?, internal: Boolean): Boolean {
diff --git a/embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/internal/payload/SpanMapperTest.kt b/embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/internal/payload/SpanMapperTest.kt
index b709b2aa1..ad46f0958 100644
--- a/embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/internal/payload/SpanMapperTest.kt
+++ b/embrace-android-sdk/src/test/java/io/embrace/android/embracesdk/internal/payload/SpanMapperTest.kt
@@ -1,7 +1,7 @@
 package io.embrace.android.embracesdk.internal.payload
 
 import io.embrace.android.embracesdk.fakes.FakeSpanData
-import io.opentelemetry.sdk.trace.data.SpanData
+import io.embrace.android.embracesdk.internal.spans.EmbraceSpanData
 import org.junit.Assert.assertEquals
 import org.junit.Test
 
@@ -9,33 +9,33 @@ internal class SpanMapperTest {
 
     @Test
     fun toSpan() {
-        val input: SpanData = FakeSpanData()
+        val input = EmbraceSpanData(FakeSpanData())
         val output = input.toNewPayload()
 
         assertEquals(input.traceId, output.traceId)
         assertEquals(input.spanId, output.spanId)
         assertEquals(input.parentSpanId, output.parentSpanId)
         assertEquals(input.name, output.name)
-        assertEquals(input.startEpochNanos, output.startTimeUnixNano)
-        assertEquals(input.endEpochNanos, output.endTimeUnixNano)
-        assertEquals(input.status.statusCode.name, checkNotNull(output.status).name)
+        assertEquals(input.startTimeNanos, output.startTimeUnixNano)
+        assertEquals(input.endTimeNanos, output.endTimeUnixNano)
+        assertEquals(input.status.name, checkNotNull(output.status).name)
 
         // validate event copied
         val inputEvent = input.events.single()
         val outputEvent = checkNotNull(output.events).single()
         assertEquals(inputEvent.name, outputEvent.name)
-        assertEquals(inputEvent.epochNanos, outputEvent.timeUnixNano)
+        assertEquals(inputEvent.timestampNanos, outputEvent.timeUnixNano)
 
         // test event attributes
-        val inputEventAttrs = checkNotNull(inputEvent.attributes?.asMap())
+        val inputEventAttrs = checkNotNull(inputEvent.attributes)
         val outputEventAttrs = checkNotNull(outputEvent.attributes?.single())
-        assertEquals(inputEventAttrs.keys.single().key, outputEventAttrs.key)
+        assertEquals(inputEventAttrs.keys.single(), outputEventAttrs.key)
         assertEquals(inputEventAttrs.values.single(), outputEventAttrs.data)
 
         // test attributes
-        val inputAttrs = checkNotNull(input.attributes?.asMap())
+        val inputAttrs = checkNotNull(input.attributes)
         val outputAttrs = checkNotNull(output.attributes?.single())
-        assertEquals(inputAttrs.keys.single().key, outputAttrs.key)
+        assertEquals(inputAttrs.keys.single(), outputAttrs.key)
         assertEquals(inputAttrs.values.single(), outputAttrs.data)
     }
 }