diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/DefaultCryptoService.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/DefaultCryptoService.kt
index 2ce517d79c..dbe9880111 100755
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/DefaultCryptoService.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/DefaultCryptoService.kt
@@ -97,6 +97,7 @@ import org.matrix.android.sdk.internal.crypto.tasks.GetDevicesTask
 import org.matrix.android.sdk.internal.crypto.tasks.SetDeviceNameTask
 import org.matrix.android.sdk.internal.crypto.tasks.UploadKeysTask
 import org.matrix.android.sdk.internal.crypto.verification.DefaultVerificationService
+import org.matrix.android.sdk.internal.crypto.verification.VerificationMessageProcessor
 import org.matrix.android.sdk.internal.di.DeviceId
 import org.matrix.android.sdk.internal.di.MoshiProvider
 import org.matrix.android.sdk.internal.di.UserId
@@ -183,6 +184,7 @@ internal class DefaultCryptoService @Inject constructor(
         private val taskExecutor: TaskExecutor,
         private val cryptoCoroutineScope: CoroutineScope,
         private val eventDecryptor: EventDecryptor,
+        private val verificationMessageProcessor: VerificationMessageProcessor,
         private val liveEventManager: Lazy<StreamEventsManager>
 ) : CryptoService {
 
@@ -197,7 +199,7 @@ internal class DefaultCryptoService @Inject constructor(
         }
     }
 
-    fun onLiveEvent(roomId: String, event: Event) {
+    fun onLiveEvent(roomId: String, event: Event, isInitialSync: Boolean) {
         // handle state events
         if (event.isStateEvent()) {
             when (event.type) {
@@ -206,6 +208,15 @@ internal class DefaultCryptoService @Inject constructor(
                 EventType.STATE_ROOM_HISTORY_VISIBILITY -> onRoomHistoryVisibilityEvent(roomId, event)
             }
         }
+
+        // handle verification
+        if (!isInitialSync) {
+            if (event.type != null && verificationMessageProcessor.shouldProcess(event.type)) {
+                cryptoCoroutineScope.launch(coroutineDispatchers.dmVerif) {
+                    verificationMessageProcessor.process(event)
+                }
+            }
+        }
     }
 
 //    val gossipingBuffer = mutableListOf<Event>()
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/tasks/EncryptEventTask.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/tasks/EncryptEventTask.kt
index 1e395796a9..ba64f0c0a5 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/tasks/EncryptEventTask.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/tasks/EncryptEventTask.kt
@@ -16,6 +16,7 @@
 package org.matrix.android.sdk.internal.crypto.tasks
 
 import org.matrix.android.sdk.api.crypto.MXCRYPTO_ALGORITHM_MEGOLM
+import dagger.Lazy
 import org.matrix.android.sdk.api.session.crypto.CryptoService
 import org.matrix.android.sdk.api.session.crypto.model.MXEncryptEventContentResult
 import org.matrix.android.sdk.api.session.crypto.model.MXEventDecryptionResult
@@ -39,7 +40,7 @@ internal interface EncryptEventTask : Task<EncryptEventTask.Params, Event> {
 
 internal class DefaultEncryptEventTask @Inject constructor(
         private val localEchoRepository: LocalEchoRepository,
-        private val cryptoService: CryptoService
+        private val cryptoService: Lazy<CryptoService>
 ) : EncryptEventTask {
     override suspend fun execute(params: EncryptEventTask.Params): Event {
         // don't want to wait for any query
@@ -59,7 +60,7 @@ internal class DefaultEncryptEventTask @Inject constructor(
 //        try {
         // let it throws
         awaitCallback<MXEncryptEventContentResult> {
-            cryptoService.encryptEventContent(localMutableContent, localEvent.type, params.roomId, it)
+            cryptoService.get().encryptEventContent(localMutableContent, localEvent.type, params.roomId, it)
         }.let { result ->
             val modifiedContent = HashMap(result.eventContent)
             params.keepKeys?.forEach { toKeep ->
@@ -80,7 +81,7 @@ internal class DefaultEncryptEventTask @Inject constructor(
                         ).toContent(),
                         forwardingCurve25519KeyChain = emptyList(),
                         senderCurve25519Key = result.eventContent["sender_key"] as? String,
-                        claimedEd25519Key = cryptoService.getMyDevice().fingerprint()
+                        claimedEd25519Key = cryptoService.get().getMyDevice().fingerprint()
                 )
             } else {
                 null
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/tasks/SendVerificationMessageTask.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/tasks/SendVerificationMessageTask.kt
index c4a6ba27d6..ca23bcd4c4 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/tasks/SendVerificationMessageTask.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/tasks/SendVerificationMessageTask.kt
@@ -47,7 +47,7 @@ internal class DefaultSendVerificationMessageTask @Inject constructor(
             localEchoRepository.updateSendState(localId, event.roomId, SendState.SENDING)
             val response = executeRequest(globalErrorReceiver) {
                 roomAPI.send(
-                        localId,
+                        txId = localId,
                         roomId = event.roomId ?: "",
                         content = event.content,
                         eventType = event.type ?: ""
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/DefaultVerificationService.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/DefaultVerificationService.kt
index 16f1f7d719..46d53355a8 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/DefaultVerificationService.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/DefaultVerificationService.kt
@@ -764,8 +764,15 @@ internal class DefaultVerificationService @Inject constructor(
             return
         }
 
+        val roomId = event.roomId
+        if (roomId == null) {
+            Timber.e("## SAS Verification missing roomId for event")
+            // TODO cancel?
+            return
+        }
+
         handleReadyReceived(event.senderId, readyReq) {
-            verificationTransportRoomMessageFactory.createTransport(event.roomId!!, it)
+            verificationTransportRoomMessageFactory.createTransport(roomId, it)
         }
     }
 
@@ -1171,6 +1178,7 @@ internal class DefaultVerificationService @Inject constructor(
         }
                 .distinct()
 
+        requestsForUser.add(verificationRequest)
         transport.sendVerificationRequest(methodValues, validLocalId, otherUserId, roomId, null) { syncedId, info ->
             // We need to update with the syncedID
             updatePendingRequest(verificationRequest.copy(
@@ -1180,7 +1188,6 @@ internal class DefaultVerificationService @Inject constructor(
             ))
         }
 
-        requestsForUser.add(verificationRequest)
         dispatchRequestAdded(verificationRequest)
 
         return verificationRequest
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/SendVerificationMessageWorker.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/SendVerificationMessageWorker.kt
deleted file mode 100644
index 0a175ae3ca..0000000000
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/SendVerificationMessageWorker.kt
+++ /dev/null
@@ -1,88 +0,0 @@
-/*
- * Copyright 2020 The Matrix.org Foundation C.I.C.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.matrix.android.sdk.internal.crypto.verification
-
-import android.content.Context
-import androidx.work.Data
-import androidx.work.WorkerParameters
-import com.squareup.moshi.JsonClass
-import org.matrix.android.sdk.api.failure.shouldBeRetried
-import org.matrix.android.sdk.internal.SessionManager
-import org.matrix.android.sdk.internal.crypto.tasks.SendVerificationMessageTask
-import org.matrix.android.sdk.internal.session.SessionComponent
-import org.matrix.android.sdk.internal.session.room.send.CancelSendTracker
-import org.matrix.android.sdk.internal.session.room.send.LocalEchoRepository
-import org.matrix.android.sdk.internal.worker.SessionSafeCoroutineWorker
-import org.matrix.android.sdk.internal.worker.SessionWorkerParams
-import timber.log.Timber
-import javax.inject.Inject
-
-/**
- * Possible previous worker: None
- * Possible next worker    : None
- */
-internal class SendVerificationMessageWorker(context: Context, params: WorkerParameters, sessionManager: SessionManager) :
-        SessionSafeCoroutineWorker<SendVerificationMessageWorker.Params>(context, params, sessionManager, Params::class.java) {
-
-    @JsonClass(generateAdapter = true)
-    internal data class Params(
-            override val sessionId: String,
-            val eventId: String,
-            override val lastFailureMessage: String? = null
-    ) : SessionWorkerParams
-
-    @Inject lateinit var sendVerificationMessageTask: SendVerificationMessageTask
-    @Inject lateinit var localEchoRepository: LocalEchoRepository
-    @Inject lateinit var cancelSendTracker: CancelSendTracker
-
-    override fun injectWith(injector: SessionComponent) {
-        injector.inject(this)
-    }
-
-    override suspend fun doSafeWork(params: Params): Result {
-        val localEvent = localEchoRepository.getUpToDateEcho(params.eventId) ?: return buildErrorResult(params, "Event not found")
-        val localEventId = localEvent.eventId ?: ""
-        val roomId = localEvent.roomId ?: ""
-
-        if (cancelSendTracker.isCancelRequestedFor(localEventId, roomId)) {
-            return Result.success()
-                    .also {
-                        cancelSendTracker.markCancelled(localEventId, roomId)
-                        Timber.e("## SendEvent: Event sending has been cancelled $localEventId")
-                    }
-        }
-
-        return try {
-            val resultEventId = sendVerificationMessageTask.execute(
-                    SendVerificationMessageTask.Params(
-                            event = localEvent
-                    )
-            )
-
-            Result.success(Data.Builder().putString(localEventId, resultEventId).build())
-        } catch (throwable: Throwable) {
-            if (throwable.shouldBeRetried()) {
-                Result.retry()
-            } else {
-                buildErrorResult(params, throwable.localizedMessage ?: "error")
-            }
-        }
-    }
-
-    override fun buildErrorParams(params: Params, message: String): Params {
-        return params.copy(lastFailureMessage = params.lastFailureMessage ?: message)
-    }
-}
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/VerificationMessageProcessor.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/VerificationMessageProcessor.kt
index 52166761ab..7e756e8914 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/VerificationMessageProcessor.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/VerificationMessageProcessor.kt
@@ -15,13 +15,9 @@
  */
 package org.matrix.android.sdk.internal.crypto.verification
 
-import io.realm.Realm
-import org.matrix.android.sdk.api.session.crypto.MXCryptoError
-import org.matrix.android.sdk.api.session.crypto.model.OlmDecryptionResult
 import org.matrix.android.sdk.api.session.crypto.verification.VerificationService
 import org.matrix.android.sdk.api.session.events.model.Event
 import org.matrix.android.sdk.api.session.events.model.EventType
-import org.matrix.android.sdk.api.session.events.model.LocalEcho
 import org.matrix.android.sdk.api.session.events.model.toModel
 import org.matrix.android.sdk.api.session.room.model.message.MessageContent
 import org.matrix.android.sdk.api.session.room.model.message.MessageRelationContent
@@ -29,20 +25,16 @@ import org.matrix.android.sdk.api.session.room.model.message.MessageType
 import org.matrix.android.sdk.api.session.room.model.message.MessageVerificationReadyContent
 import org.matrix.android.sdk.api.session.room.model.message.MessageVerificationRequestContent
 import org.matrix.android.sdk.api.session.room.model.message.MessageVerificationStartContent
-import org.matrix.android.sdk.internal.crypto.EventDecryptor
-import org.matrix.android.sdk.internal.database.model.EventInsertType
 import org.matrix.android.sdk.internal.di.DeviceId
 import org.matrix.android.sdk.internal.di.UserId
-import org.matrix.android.sdk.internal.session.EventInsertLiveProcessor
 import timber.log.Timber
 import javax.inject.Inject
 
 internal class VerificationMessageProcessor @Inject constructor(
-        private val eventDecryptor: EventDecryptor,
         private val verificationService: DefaultVerificationService,
         @UserId private val userId: String,
         @DeviceId private val deviceId: String?
-) : EventInsertLiveProcessor {
+) {
 
     private val transactionsHandledByOtherDevice = ArrayList<String>()
 
@@ -58,41 +50,20 @@ internal class VerificationMessageProcessor @Inject constructor(
             EventType.ENCRYPTED
     )
 
-    override fun shouldProcess(eventId: String, eventType: String, insertType: EventInsertType): Boolean {
-        if (insertType != EventInsertType.INCREMENTAL_SYNC) {
-            return false
-        }
-        return allowedTypes.contains(eventType) && !LocalEcho.isLocalEchoId(eventId)
+    fun shouldProcess(eventType: String): Boolean {
+        return allowedTypes.contains(eventType)
     }
 
-    override suspend fun process(realm: Realm, event: Event) {
-        Timber.v("## SAS Verification live observer: received msgId: ${event.eventId} msgtype: ${event.type} from ${event.senderId}")
+    suspend fun process(event: Event) {
+        Timber.v("## SAS Verification live observer: received msgId: ${event.eventId} msgtype: ${event.getClearType()} from ${event.senderId}")
 
         // If the request is in the future by more than 5 minutes or more than 10 minutes in the past,
         // the message should be ignored by the receiver.
 
-        if (!VerificationService.isValidRequest(event.ageLocalTs
-                        ?: event.originServerTs)) return Unit.also {
-            Timber.d("## SAS Verification live observer: msgId: ${event.eventId} is outdated")
+        if (event.ageLocalTs != null && !VerificationService.isValidRequest(event.ageLocalTs)) return Unit.also {
+            Timber.d("## SAS Verification live observer: msgId: ${event.eventId} is outdated age:$event.ageLocalTs ms")
         }
 
-        // decrypt if needed?
-        if (event.isEncrypted() && event.mxDecryptionResult == null) {
-            // TODO use a global event decryptor? attache to session and that listen to new sessionId?
-            // for now decrypt sync
-            try {
-                val result = eventDecryptor.decryptEvent(event, "")
-                event.mxDecryptionResult = OlmDecryptionResult(
-                        payload = result.clearEvent,
-                        senderKey = result.senderCurve25519Key,
-                        keysClaimed = result.claimedEd25519Key?.let { mapOf("ed25519" to it) },
-                        forwardingCurve25519KeyChain = result.forwardingCurve25519KeyChain
-                )
-            } catch (e: MXCryptoError) {
-                Timber.e("## SAS Failed to decrypt event: ${event.eventId}")
-                verificationService.onPotentiallyInterestingEventRoomFailToDecrypt(event)
-            }
-        }
         Timber.v("## SAS Verification live observer: received msgId: ${event.eventId} type: ${event.getClearType()}")
 
         // Relates to is not encrypted
@@ -101,7 +72,6 @@ internal class VerificationMessageProcessor @Inject constructor(
         if (event.senderId == userId) {
             // If it's send from me, we need to keep track of Requests or Start
             // done from another device of mine
-
             if (EventType.MESSAGE == event.getClearType()) {
                 val msgType = event.getClearContent().toModel<MessageContent>()?.msgType
                 if (MessageType.MSGTYPE_VERIFICATION_REQUEST == msgType) {
@@ -136,6 +106,8 @@ internal class VerificationMessageProcessor @Inject constructor(
                     transactionsHandledByOtherDevice.remove(it)
                     verificationService.onRoomRequestHandledByOtherDevice(event)
                 }
+            } else if (EventType.ENCRYPTED == event.getClearType()) {
+                verificationService.onPotentiallyInterestingEventRoomFailToDecrypt(event)
             }
 
             Timber.v("## SAS Verification ignoring message sent by me: ${event.eventId} type: ${event.getClearType()}")
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/VerificationTransportRoomMessage.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/VerificationTransportRoomMessage.kt
index 49235c5744..b6eba6b3b4 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/VerificationTransportRoomMessage.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/VerificationTransportRoomMessage.kt
@@ -15,14 +15,9 @@
  */
 package org.matrix.android.sdk.internal.crypto.verification
 
-import androidx.lifecycle.Observer
-import androidx.work.BackoffPolicy
-import androidx.work.Data
-import androidx.work.ExistingWorkPolicy
-import androidx.work.Operation
-import androidx.work.WorkInfo
 import kotlinx.coroutines.CoroutineScope
-import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.SupervisorJob
+import kotlinx.coroutines.asCoroutineDispatcher
 import kotlinx.coroutines.launch
 import org.matrix.android.sdk.api.session.crypto.verification.CancelCode
 import org.matrix.android.sdk.api.session.crypto.verification.ValidVerificationInfoRequest
@@ -45,25 +40,25 @@ import org.matrix.android.sdk.api.session.room.model.message.MessageVerification
 import org.matrix.android.sdk.api.session.room.model.relation.RelationDefaultContent
 import org.matrix.android.sdk.internal.crypto.model.rest.VERIFICATION_METHOD_RECIPROCATE
 import org.matrix.android.sdk.internal.crypto.model.rest.VERIFICATION_METHOD_SAS
-import org.matrix.android.sdk.internal.di.WorkManagerProvider
+import org.matrix.android.sdk.internal.crypto.tasks.SendVerificationMessageTask
 import org.matrix.android.sdk.internal.session.room.send.LocalEchoEventFactory
-import org.matrix.android.sdk.internal.worker.SessionSafeCoroutineWorker
-import org.matrix.android.sdk.internal.worker.WorkerParamsFactory
+import org.matrix.android.sdk.internal.task.SemaphoreCoroutineSequencer
 import timber.log.Timber
-import java.util.UUID
-import java.util.concurrent.TimeUnit
+import java.util.concurrent.Executors
 
 internal class VerificationTransportRoomMessage(
-        private val workManagerProvider: WorkManagerProvider,
-        private val sessionId: String,
+        private val sendVerificationMessageTask: SendVerificationMessageTask,
         private val userId: String,
         private val userDeviceId: String?,
         private val roomId: String,
         private val localEchoEventFactory: LocalEchoEventFactory,
-        private val tx: DefaultVerificationTransaction?,
-        private val coroutineScope: CoroutineScope
+        private val tx: DefaultVerificationTransaction?
 ) : VerificationTransport {
 
+    private val dispatcher = Executors.newSingleThreadExecutor().asCoroutineDispatcher()
+    private val verificationSenderScope = CoroutineScope(SupervisorJob() + dispatcher)
+    private val sequencer = SemaphoreCoroutineSequencer()
+
     override fun <T> sendToOther(type: String,
                                  verificationInfo: VerificationInfo<T>,
                                  nextState: VerificationTxState,
@@ -77,68 +72,22 @@ internal class VerificationTransportRoomMessage(
                 content = verificationInfo.toEventContent()!!
         )
 
-        val workerParams = WorkerParamsFactory.toData(SendVerificationMessageWorker.Params(
-                sessionId = sessionId,
-                eventId = event.eventId ?: ""
-        ))
-        val enqueueInfo = enqueueSendWork(workerParams)
-
-        // I cannot just listen to the given work request, because when used in a uniqueWork,
-        // The callback is called while it is still Running ...
-
-//        Futures.addCallback(enqueueInfo.first.result, object : FutureCallback<Operation.State.SUCCESS> {
-//            override fun onSuccess(result: Operation.State.SUCCESS?) {
-//                if (onDone != null) {
-//                    onDone()
-//                } else {
-//                    tx?.state = nextState
-//                }
-//            }
-//
-//            override fun onFailure(t: Throwable) {
-//                Timber.e("## SAS verification [${tx?.transactionId}] failed to send toDevice in state : ${tx?.state}, reason: ${t.localizedMessage}")
-//                tx?.cancel(onErrorReason)
-//            }
-//        }, listenerExecutor)
-
-        val workLiveData = workManagerProvider.workManager
-                .getWorkInfosForUniqueWorkLiveData(uniqueQueueName())
-
-        val observer = object : Observer<List<WorkInfo>> {
-            override fun onChanged(workInfoList: List<WorkInfo>?) {
-                workInfoList
-                        ?.firstOrNull { it.id == enqueueInfo.second }
-                        ?.let { wInfo ->
-                            when (wInfo.state) {
-                                WorkInfo.State.FAILED    -> {
-                                    tx?.cancel(onErrorReason)
-                                    workLiveData.removeObserver(this)
-                                }
-                                WorkInfo.State.SUCCEEDED -> {
-                                    if (SessionSafeCoroutineWorker.hasFailed(wInfo.outputData)) {
-                                        Timber.e("## SAS verification [${tx?.transactionId}] failed to send verification message in state : ${tx?.state}")
-                                        tx?.cancel(onErrorReason)
-                                    } else {
-                                        if (onDone != null) {
-                                            onDone()
-                                        } else {
-                                            tx?.state = nextState
-                                        }
-                                    }
-                                    workLiveData.removeObserver(this)
-                                }
-                                else                     -> {
-                                    // nop
-                                }
-                            }
-                        }
+        verificationSenderScope.launch {
+            sequencer.post {
+                try {
+                    val params = SendVerificationMessageTask.Params(event)
+                    sendVerificationMessageTask.executeRetry(params, 5)
+                    // Do I need to update local echo state to sent?
+                    if (onDone != null) {
+                        onDone()
+                    } else {
+                        tx?.state = nextState
+                    }
+                } catch (failure: Throwable) {
+                    tx?.cancel(onErrorReason)
+                }
             }
         }
-
-        // TODO listen to DB to get synced info
-        coroutineScope.launch(Dispatchers.Main) {
-            workLiveData.observeForever(observer)
-        }
     }
 
     override fun sendVerificationRequest(supportedMethods: List<String>,
@@ -169,58 +118,24 @@ internal class VerificationTransportRoomMessage(
         val content = info.toContent()
 
         val event = createEventAndLocalEcho(
-                localId,
-                EventType.MESSAGE,
-                roomId,
-                content
+                localId = localId,
+                type = EventType.MESSAGE,
+                roomId = roomId,
+                content = content
         )
 
-        val workerParams = WorkerParamsFactory.toData(SendVerificationMessageWorker.Params(
-                sessionId = sessionId,
-                eventId = event.eventId ?: ""
-        ))
-
-        val workRequest = workManagerProvider.matrixOneTimeWorkRequestBuilder<SendVerificationMessageWorker>()
-                .setConstraints(WorkManagerProvider.workConstraints)
-                .setInputData(workerParams)
-                .setBackoffCriteria(BackoffPolicy.LINEAR, WorkManagerProvider.BACKOFF_DELAY_MILLIS, TimeUnit.MILLISECONDS)
-                .build()
-
-        workManagerProvider.workManager
-                .beginUniqueWork("${roomId}_VerificationWork", ExistingWorkPolicy.APPEND_OR_REPLACE, workRequest)
-                .enqueue()
-
-        // I cannot just listen to the given work request, because when used in a uniqueWork,
-        // The callback is called while it is still Running ...
-
-        val workLiveData = workManagerProvider.workManager
-                .getWorkInfosForUniqueWorkLiveData("${roomId}_VerificationWork")
-
-        val observer = object : Observer<List<WorkInfo>> {
-            override fun onChanged(workInfoList: List<WorkInfo>?) {
-                workInfoList
-                        ?.filter { it.state == WorkInfo.State.SUCCEEDED }
-                        ?.firstOrNull { it.id == workRequest.id }
-                        ?.let { wInfo ->
-                            if (SessionSafeCoroutineWorker.hasFailed(wInfo.outputData)) {
-                                callback(null, null)
-                            } else {
-                                val eventId = wInfo.outputData.getString(localId)
-                                if (eventId != null) {
-                                    callback(eventId, validInfo)
-                                } else {
-                                    callback(null, null)
-                                }
-                            }
-                            workLiveData.removeObserver(this)
-                        }
+        verificationSenderScope.launch {
+            val params = SendVerificationMessageTask.Params(event)
+            sequencer.post {
+                try {
+                    val eventId = sendVerificationMessageTask.executeRetry(params, 5)
+                    // Do I need to update local echo state to sent?
+                    callback(eventId, validInfo)
+                } catch (failure: Throwable) {
+                    callback(null, null)
+                }
             }
         }
-
-        // TODO listen to DB to get synced info
-        coroutineScope.launch(Dispatchers.Main) {
-            workLiveData.observeForever(observer)
-        }
     }
 
     override fun cancelTransaction(transactionId: String, otherUserId: String, otherUserDeviceId: String?, code: CancelCode) {
@@ -230,11 +145,17 @@ internal class VerificationTransportRoomMessage(
                 roomId = roomId,
                 content = MessageVerificationCancelContent.create(transactionId, code).toContent()
         )
-        val workerParams = WorkerParamsFactory.toData(SendVerificationMessageWorker.Params(
-                sessionId = sessionId,
-                eventId = event.eventId ?: ""
-        ))
-        enqueueSendWork(workerParams)
+
+        verificationSenderScope.launch {
+            sequencer.post {
+                try {
+                    val params = SendVerificationMessageTask.Params(event)
+                    sendVerificationMessageTask.executeRetry(params, 5)
+                } catch (failure: Throwable) {
+                    Timber.w("")
+                }
+            }
+        }
     }
 
     override fun done(transactionId: String,
@@ -250,44 +171,56 @@ internal class VerificationTransportRoomMessage(
                         )
                 ).toContent()
         )
-        val workerParams = WorkerParamsFactory.toData(SendVerificationMessageWorker.Params(
-                sessionId = sessionId,
-                eventId = event.eventId ?: ""
-        ))
-        val enqueueInfo = enqueueSendWork(workerParams)
-
-        val workLiveData = workManagerProvider.workManager
-                .getWorkInfosForUniqueWorkLiveData(uniqueQueueName())
-        val observer = object : Observer<List<WorkInfo>> {
-            override fun onChanged(workInfoList: List<WorkInfo>?) {
-                workInfoList
-                        ?.filter { it.state == WorkInfo.State.SUCCEEDED }
-                        ?.firstOrNull { it.id == enqueueInfo.second }
-                        ?.let { _ ->
-                            onDone?.invoke()
-                            workLiveData.removeObserver(this)
-                        }
+        verificationSenderScope.launch {
+            sequencer.post {
+                try {
+                    val params = SendVerificationMessageTask.Params(event)
+                    sendVerificationMessageTask.executeRetry(params, 5)
+                } catch (failure: Throwable) {
+                    Timber.w("")
+                } finally {
+                    onDone?.invoke()
+                }
             }
         }
-
-        // TODO listen to DB to get synced info
-        coroutineScope.launch(Dispatchers.Main) {
-            workLiveData.observeForever(observer)
-        }
+//        val workerParams = WorkerParamsFactory.toData(SendVerificationMessageWorker.Params(
+//                sessionId = sessionId,
+//                eventId = event.eventId ?: ""
+//        ))
+//        val enqueueInfo = enqueueSendWork(workerParams)
+//
+//        val workLiveData = workManagerProvider.workManager
+//                .getWorkInfosForUniqueWorkLiveData(uniqueQueueName())
+//        val observer = object : Observer<List<WorkInfo>> {
+//            override fun onChanged(workInfoList: List<WorkInfo>?) {
+//                workInfoList
+//                        ?.filter { it.state == WorkInfo.State.SUCCEEDED }
+//                        ?.firstOrNull { it.id == enqueueInfo.second }
+//                        ?.let { _ ->
+//                            onDone?.invoke()
+//                            workLiveData.removeObserver(this)
+//                        }
+//            }
+//        }
+//
+//        // TODO listen to DB to get synced info
+//        coroutineScope.launch(Dispatchers.Main) {
+//            workLiveData.observeForever(observer)
+//        }
     }
 
-    private fun enqueueSendWork(workerParams: Data): Pair<Operation, UUID> {
-        val workRequest = workManagerProvider.matrixOneTimeWorkRequestBuilder<SendVerificationMessageWorker>()
-                .setConstraints(WorkManagerProvider.workConstraints)
-                .setInputData(workerParams)
-                .setBackoffCriteria(BackoffPolicy.LINEAR, WorkManagerProvider.BACKOFF_DELAY_MILLIS, TimeUnit.MILLISECONDS)
-                .build()
-        return workManagerProvider.workManager
-                .beginUniqueWork(uniqueQueueName(), ExistingWorkPolicy.APPEND_OR_REPLACE, workRequest)
-                .enqueue() to workRequest.id
-    }
+//    private fun enqueueSendWork(workerParams: Data): Pair<Operation, UUID> {
+//        val workRequest = workManagerProvider.matrixOneTimeWorkRequestBuilder<SendVerificationMessageWorker>()
+//                .setConstraints(WorkManagerProvider.workConstraints)
+//                .setInputData(workerParams)
+//                .setBackoffCriteria(BackoffPolicy.LINEAR, WorkManagerProvider.BACKOFF_DELAY_MILLIS, TimeUnit.MILLISECONDS)
+//                .build()
+//        return workManagerProvider.workManager
+//                .beginUniqueWork(uniqueQueueName(), ExistingWorkPolicy.APPEND_OR_REPLACE, workRequest)
+//                .enqueue() to workRequest.id
+//    }
 
-    private fun uniqueQueueName() = "${roomId}_VerificationWork"
+//    private fun uniqueQueueName() = "${roomId}_VerificationWork"
 
     override fun createAccept(tid: String,
                               keyAgreementProtocol: String,
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/VerificationTransportRoomMessageFactory.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/VerificationTransportRoomMessageFactory.kt
index f89127273b..efbdd9c175 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/VerificationTransportRoomMessageFactory.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/verification/VerificationTransportRoomMessageFactory.kt
@@ -16,34 +16,28 @@
 
 package org.matrix.android.sdk.internal.crypto.verification
 
+import org.matrix.android.sdk.internal.crypto.tasks.SendVerificationMessageTask
 import org.matrix.android.sdk.internal.di.DeviceId
-import org.matrix.android.sdk.internal.di.SessionId
 import org.matrix.android.sdk.internal.di.UserId
-import org.matrix.android.sdk.internal.di.WorkManagerProvider
 import org.matrix.android.sdk.internal.session.room.send.LocalEchoEventFactory
-import org.matrix.android.sdk.internal.task.TaskExecutor
 import javax.inject.Inject
 
 internal class VerificationTransportRoomMessageFactory @Inject constructor(
-        private val workManagerProvider: WorkManagerProvider,
-        @SessionId
-        private val sessionId: String,
+        private val sendVerificationMessageTask: SendVerificationMessageTask,
         @UserId
         private val userId: String,
         @DeviceId
         private val deviceId: String?,
-        private val localEchoEventFactory: LocalEchoEventFactory,
-        private val taskExecutor: TaskExecutor
+        private val localEchoEventFactory: LocalEchoEventFactory
 ) {
 
     fun createTransport(roomId: String, tx: DefaultVerificationTransaction?): VerificationTransportRoomMessage {
-        return VerificationTransportRoomMessage(workManagerProvider,
-                sessionId,
-                userId,
-                deviceId,
-                roomId,
-                localEchoEventFactory,
-                tx,
-                taskExecutor.executorScope)
+        return VerificationTransportRoomMessage(
+                sendVerificationMessageTask = sendVerificationMessageTask,
+                userId = userId,
+                userDeviceId = deviceId,
+                roomId = roomId,
+                localEchoEventFactory = localEchoEventFactory,
+                tx = tx)
     }
 }
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/SessionComponent.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/SessionComponent.kt
index 4c1a06f1c7..e1e4f7fd50 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/SessionComponent.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/SessionComponent.kt
@@ -23,7 +23,6 @@ import org.matrix.android.sdk.api.auth.data.SessionParams
 import org.matrix.android.sdk.api.session.Session
 import org.matrix.android.sdk.internal.crypto.CryptoModule
 import org.matrix.android.sdk.internal.crypto.crosssigning.UpdateTrustWorker
-import org.matrix.android.sdk.internal.crypto.verification.SendVerificationMessageWorker
 import org.matrix.android.sdk.internal.di.MatrixComponent
 import org.matrix.android.sdk.internal.federation.FederationModule
 import org.matrix.android.sdk.internal.network.NetworkConnectivityChecker
@@ -129,8 +128,6 @@ internal interface SessionComponent {
 
     fun inject(worker: AddPusherWorker)
 
-    fun inject(worker: SendVerificationMessageWorker)
-
     fun inject(worker: UpdateTrustWorker)
 
     @Component.Factory
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/SessionModule.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/SessionModule.kt
index 0aae9f3105..7ceb89e892 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/SessionModule.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/SessionModule.kt
@@ -49,7 +49,6 @@ import org.matrix.android.sdk.api.util.md5
 import org.matrix.android.sdk.internal.crypto.secrets.DefaultSharedSecretStorageService
 import org.matrix.android.sdk.internal.crypto.tasks.DefaultRedactEventTask
 import org.matrix.android.sdk.internal.crypto.tasks.RedactEventTask
-import org.matrix.android.sdk.internal.crypto.verification.VerificationMessageProcessor
 import org.matrix.android.sdk.internal.database.EventInsertLiveObserver
 import org.matrix.android.sdk.internal.database.RealmSessionProvider
 import org.matrix.android.sdk.internal.database.SessionRealmConfigurationFactory
@@ -318,10 +317,6 @@ internal abstract class SessionModule {
     @IntoSet
     abstract fun bindRoomCreateEventProcessor(processor: RoomCreateEventProcessor): EventInsertLiveProcessor
 
-    @Binds
-    @IntoSet
-    abstract fun bindVerificationMessageProcessor(processor: VerificationMessageProcessor): EventInsertLiveProcessor
-
     @Binds
     @IntoSet
     abstract fun bindCallEventProcessor(processor: CallEventProcessor): EventInsertLiveProcessor
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/sync/handler/room/RoomSyncHandler.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/sync/handler/room/RoomSyncHandler.kt
index afd8e1bb99..18cc420e1a 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/sync/handler/room/RoomSyncHandler.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/sync/handler/room/RoomSyncHandler.kt
@@ -378,7 +378,10 @@ internal class RoomSyncHandler @Inject constructor(private val readReceiptHandle
         val roomMemberContentsByUser = HashMap<String, RoomMemberContent?>()
 
         val optimizedThreadSummaryMap = hashMapOf<String, EventEntity>()
-        for (event in eventList) {
+        for (rawEvent in eventList) {
+            // It's annoying roomId is not there, but lot of code rely on it.
+            // And had to do it now as copy would delete all decryption results..
+            val event = rawEvent.copy(roomId = roomId)
             if (event.eventId == null || event.senderId == null || event.type == null) {
                 continue
             }
@@ -445,7 +448,7 @@ internal class RoomSyncHandler @Inject constructor(private val readReceiptHandle
                 }
             }
             // Give info to crypto module
-            cryptoService.onLiveEvent(roomEntity.roomId, event)
+            cryptoService.onLiveEvent(roomEntity.roomId, event, isInitialSync)
 
             // Try to remove local echo
             event.unsignedData?.transactionId?.also {
diff --git a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/worker/MatrixWorkerFactory.kt b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/worker/MatrixWorkerFactory.kt
index 94dd36114b..8e5576d2ce 100644
--- a/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/worker/MatrixWorkerFactory.kt
+++ b/matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/worker/MatrixWorkerFactory.kt
@@ -23,7 +23,6 @@ import androidx.work.WorkerFactory
 import androidx.work.WorkerParameters
 import org.matrix.android.sdk.internal.SessionManager
 import org.matrix.android.sdk.internal.crypto.crosssigning.UpdateTrustWorker
-import org.matrix.android.sdk.internal.crypto.verification.SendVerificationMessageWorker
 import org.matrix.android.sdk.internal.di.MatrixScope
 import org.matrix.android.sdk.internal.session.content.UploadContentWorker
 import org.matrix.android.sdk.internal.session.group.GetGroupDataWorker
@@ -61,8 +60,6 @@ internal class MatrixWorkerFactory @Inject constructor(private val sessionManage
                 RedactEventWorker(appContext, workerParameters, sessionManager)
             SendEventWorker::class.java.name                      ->
                 SendEventWorker(appContext, workerParameters, sessionManager)
-            SendVerificationMessageWorker::class.java.name        ->
-                SendVerificationMessageWorker(appContext, workerParameters, sessionManager)
             SyncWorker::class.java.name                           ->
                 SyncWorker(appContext, workerParameters, sessionManager)
             UpdateTrustWorker::class.java.name                    ->