diff --git a/core/src/commonMain/kotlin/com/powersync/bucket/BucketStorage.kt b/core/src/commonMain/kotlin/com/powersync/bucket/BucketStorage.kt
index 5e5e0728..443743a9 100644
--- a/core/src/commonMain/kotlin/com/powersync/bucket/BucketStorage.kt
+++ b/core/src/commonMain/kotlin/com/powersync/bucket/BucketStorage.kt
@@ -44,6 +44,13 @@ internal class BucketStorage(
         return MAX_OP_ID
     }
 
+    suspend fun getClientId(): String {
+        val id = db.getOptional("SELECT powersync_client_id() as client_id") {
+            it.getString(0)!!
+        }
+        return id ?: throw IllegalStateException("Client ID not found")
+    }
+
     suspend fun hasCrud(): Boolean {
         return db.queries.hasCrud().awaitAsOneOrNull() == 1L
     }
@@ -140,7 +147,7 @@ internal class BucketStorage(
         }
 
         val completedSync = db.getOptional(
-            "SELECT name, last_applied_op FROM ps_buckets WHERE last_applied_op > 0 LIMIT 1",
+            "SELECT powersync_last_synced_at()",
             mapper = { cursor ->
                 cursor.getString(0)!!
             })
diff --git a/core/src/commonMain/kotlin/com/powersync/db/PowerSyncDatabaseImpl.kt b/core/src/commonMain/kotlin/com/powersync/db/PowerSyncDatabaseImpl.kt
index 53842877..6cee8ffc 100644
--- a/core/src/commonMain/kotlin/com/powersync/db/PowerSyncDatabaseImpl.kt
+++ b/core/src/commonMain/kotlin/com/powersync/db/PowerSyncDatabaseImpl.kt
@@ -30,6 +30,8 @@ import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.debounce
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.runBlocking
+import kotlinx.datetime.Instant
+import kotlinx.datetime.toLocalDateTime
 import kotlinx.serialization.encodeToString
 
 /**
@@ -67,8 +69,10 @@ internal class PowerSyncDatabaseImpl(
         runBlocking {
             val sqliteVersion = internalDb.queries.sqliteVersion().awaitAsOne()
             logger.d { "SQLiteVersion: $sqliteVersion" }
+            checkVersion()
             logger.d { "PowerSyncVersion: ${getPowerSyncVersion()}" }
             applySchema()
+            updateHasSynced()
         }
     }
 
@@ -105,6 +109,7 @@ internal class PowerSyncDatabaseImpl(
                     connecting = it.connecting,
                     downloading = it.downloading,
                     lastSyncedAt = it.lastSyncedAt,
+                    hasSynced = it.hasSynced,
                     uploadError = it.uploadError,
                     downloadError = it.downloadError,
                     clearDownloadError = it.downloadError == null,
@@ -247,12 +252,12 @@ internal class PowerSyncDatabaseImpl(
 
             if (writeCheckpoint != null && bucketStorage.hasCrud()) {
                 tx.execute(
-                    "UPDATE ps_buckets SET target_op = ? WHERE name='\$local'",
+                    "UPDATE ps_buckets SET target_op = CAST(? as INTEGER) WHERE name='\$local'",
                     listOf(writeCheckpoint),
                 )
             } else {
                 tx.execute(
-                    "UPDATE ps_buckets SET target_op = ? WHERE name='\$local'",
+                    "UPDATE ps_buckets SET target_op = CAST(? as INTEGER) WHERE name='\$local'",
                     listOf(bucketStorage.getMaxOpId()),
                 )
             }
@@ -273,7 +278,7 @@ internal class PowerSyncDatabaseImpl(
             syncStream = null
         }
 
-        currentStatus.update(connected = false, connecting = false)
+        currentStatus.update(connected = false, connecting = false, lastSyncedAt = currentStatus.lastSyncedAt)
     }
 
     override suspend fun disconnectAndClear(clearLocal: Boolean) {
@@ -293,4 +298,43 @@ internal class PowerSyncDatabaseImpl(
             }
         }
     }
+
+    private suspend fun updateHasSynced() {
+        // Query the database to see if any data has been synced.
+        val timestamp = internalDb.getOptional("SELECT powersync_last_synced_at() as synced_at", null) { cursor ->
+            cursor.getString(0)!!
+        }
+
+        val hasSynced = timestamp != null
+        if (hasSynced != currentStatus.hasSynced) {
+            val formattedDateTime = "${timestamp!!.replace(" ","T").toLocalDateTime()}Z"
+            val lastSyncedAt = Instant.parse(formattedDateTime)
+            currentStatus.update(hasSynced = hasSynced, lastSyncedAt = lastSyncedAt)
+        }
+    }
+
+    /**
+     * Check that a supported version of the powersync extension is loaded.
+     */
+    private suspend fun checkVersion() {
+        val version: String = try {
+            getPowerSyncVersion()
+        } catch (e: Exception) {
+            throw Exception("The powersync extension is not loaded correctly. Details: $e")
+        }
+
+        // Parse version
+        val versionInts: List<Int> = try {
+            version.split(Regex("[./]"))
+                .take(3)
+                .map { it.toInt() }
+        } catch (e: Exception) {
+            throw Exception("Unsupported powersync extension version. Need ^0.2.0, got: $version. Details: $e")
+        }
+
+        // Validate ^0.2.0
+        if (versionInts[0] != 0 || versionInts[1] != 2 || versionInts[2] < 0) {
+            throw Exception("Unsupported powersync extension version. Need ^0.2.0, got: $version")
+        }
+    }
 }
diff --git a/core/src/commonMain/kotlin/com/powersync/sync/StreamingSyncRequest.kt b/core/src/commonMain/kotlin/com/powersync/sync/StreamingSyncRequest.kt
index 9e1c4f38..6fda9fe4 100644
--- a/core/src/commonMain/kotlin/com/powersync/sync/StreamingSyncRequest.kt
+++ b/core/src/commonMain/kotlin/com/powersync/sync/StreamingSyncRequest.kt
@@ -3,11 +3,14 @@ package com.powersync.sync
 import com.powersync.bucket.BucketRequest
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
+import kotlinx.serialization.json.JsonObject
 
 @Serializable
 internal data class StreamingSyncRequest(
     val buckets: List<BucketRequest>,
     @SerialName("include_checksum") val includeChecksum: Boolean = true,
+    @SerialName("client_id") val clientId: String,
+    val parameters: JsonObject = JsonObject(mapOf())
 ) {
     @SerialName("raw_data") private val rawData: Boolean = true
-}
+}
\ No newline at end of file
diff --git a/core/src/commonMain/kotlin/com/powersync/sync/SyncStatus.kt b/core/src/commonMain/kotlin/com/powersync/sync/SyncStatus.kt
index 206deb32..11510524 100644
--- a/core/src/commonMain/kotlin/com/powersync/sync/SyncStatus.kt
+++ b/core/src/commonMain/kotlin/com/powersync/sync/SyncStatus.kt
@@ -40,6 +40,13 @@ public interface SyncStatusData {
      */
     public val lastSyncedAt: Instant?
 
+    /**
+     * Indicates whether there has been at least one full sync, if any.
+     *
+     * Is null when unknown, for example when state is still being loaded from the database.
+     */
+    public val hasSynced: Boolean?
+
     /**
      * Error during uploading.
      *
@@ -66,27 +73,12 @@ internal data class SyncStatusDataContainer(
     override val downloading: Boolean = false,
     override val uploading: Boolean = false,
     override val lastSyncedAt: Instant? = null,
+    override val hasSynced: Boolean? = null,
     override val uploadError: Any? = null,
     override val downloadError: Any? = null,
 ) : SyncStatusData {
     override val anyError
         get() = downloadError ?: uploadError
-
-    /**
-     * Builder for creating a new SyncStatusDataContainer with updated values.
-     */
-    class Builder(private var data: SyncStatusDataContainer) {
-        fun connected(value: Boolean) = apply { data = data.copy(connected = value) }
-        fun connecting(value: Boolean) = apply { data = data.copy(connecting = value) }
-        fun downloading(value: Boolean) = apply { data = data.copy(downloading = value) }
-        fun uploading(value: Boolean) = apply { data = data.copy(uploading = value) }
-        fun lastSyncedAt(value: Instant?) = apply { data = data.copy(lastSyncedAt = value) }
-        fun uploadError(value: Any?) = apply { data = data.copy(uploadError = value) }
-        fun downloadError(value: Any?) = apply { data = data.copy(downloadError = value) }
-        fun clearUploadError() = apply { data = data.copy(uploadError = null) }
-        fun clearDownloadError() = apply { data = data.copy(downloadError = null) }
-        fun build() = data
-    }
 }
 
 
@@ -102,19 +94,6 @@ public data class SyncStatus internal constructor(
         return stateFlow.asSharedFlow()
     }
 
-    /**
-     * Updates the internal sync status indicators and emits Flow updates
-     * Usage:
-     * ```
-     * syncStatus.update {
-     *    connected(true)
-     * }
-     */
-    internal fun update(builder: SyncStatusDataContainer.Builder.() -> Unit) {
-        data = SyncStatusDataContainer.Builder(data).apply(builder).build()
-        stateFlow.value = data
-    }
-
     /**
      * Updates the internal sync status indicators and emits Flow updates
      */
@@ -123,6 +102,7 @@ public data class SyncStatus internal constructor(
         connecting: Boolean = data.connecting,
         downloading: Boolean = data.downloading,
         uploading: Boolean = data.uploading,
+        hasSynced: Boolean? = data.hasSynced,
         lastSyncedAt: Instant? = data.lastSyncedAt,
         uploadError: Any? = data.uploadError,
         downloadError: Any? = data.downloadError,
@@ -135,6 +115,7 @@ public data class SyncStatus internal constructor(
             downloading = downloading,
             uploading = uploading,
             lastSyncedAt = lastSyncedAt,
+            hasSynced = hasSynced,
             uploadError = if (clearUploadError == true) null else uploadError,
             downloadError = if (clearDownloadError == true) null else downloadError,
         )
@@ -159,6 +140,9 @@ public data class SyncStatus internal constructor(
     override val lastSyncedAt: Instant?
         get() = data.lastSyncedAt
 
+    override val hasSynced: Boolean?
+        get() = data.hasSynced
+
     override val uploadError: Any?
         get() = data.uploadError
 
@@ -166,7 +150,7 @@ public data class SyncStatus internal constructor(
         get() = data.downloadError
 
     override fun toString(): String {
-        return "SyncStatus(connected=$connected, connecting=$connecting, downloading=$downloading, uploading=$uploading, lastSyncedAt=$lastSyncedAt, error=$anyError)"
+        return "SyncStatus(connected=$connected, connecting=$connecting, downloading=$downloading, uploading=$uploading, lastSyncedAt=$lastSyncedAt, hasSynced: $hasSynced, error=$anyError)"
     }
 
     public companion object {
diff --git a/core/src/commonMain/kotlin/com/powersync/sync/SyncStream.kt b/core/src/commonMain/kotlin/com/powersync/sync/SyncStream.kt
index f2aa8927..92eb7422 100644
--- a/core/src/commonMain/kotlin/com/powersync/sync/SyncStream.kt
+++ b/core/src/commonMain/kotlin/com/powersync/sync/SyncStream.kt
@@ -50,6 +50,8 @@ internal class SyncStream(
      */
     var status = SyncStatus()
 
+    private var clientId: String? = null
+
     private val httpClient: HttpClient = HttpClient {
         install(HttpTimeout)
         install(ContentNegotiation)
@@ -84,6 +86,7 @@ internal class SyncStream(
 
     suspend fun streamingSync() {
         var invalidCredentials = false
+        clientId = bucketStorage.getClientId()
         while (true) {
             status.update(connecting = true)
             try {
@@ -164,7 +167,7 @@ internal class SyncStream(
     private suspend fun getWriteCheckpoint(): String {
         val credentials = connector.getCredentialsCached()
         require(credentials != null) { "Not logged in" }
-        val uri = credentials.endpointUri("write-checkpoint2.json")
+        val uri = credentials.endpointUri("write-checkpoint2.json?client_id=$clientId'")
 
         val response = httpClient.get(uri) {
             contentType(ContentType.Application.Json)
@@ -242,6 +245,7 @@ internal class SyncStream(
 
         val req = StreamingSyncRequest(
             buckets = initialBuckets.map { (bucket, after) -> BucketRequest(bucket, after) },
+            clientId = clientId!!
         )
 
         streamingSyncRequest(req).collect { value ->
diff --git a/core/src/commonTest/kotlin/com/powersync/sync/StreamingSyncRequestTest.kt b/core/src/commonTest/kotlin/com/powersync/sync/StreamingSyncRequestTest.kt
new file mode 100644
index 00000000..a5c4557a
--- /dev/null
+++ b/core/src/commonTest/kotlin/com/powersync/sync/StreamingSyncRequestTest.kt
@@ -0,0 +1,71 @@
+import com.powersync.bucket.BucketRequest
+import com.powersync.sync.StreamingSyncRequest
+import kotlinx.serialization.encodeToString
+import kotlinx.serialization.json.Json
+import kotlinx.serialization.json.JsonObject
+import kotlinx.serialization.json.JsonPrimitive
+import kotlin.test.*
+
+class StreamingSyncRequestTest {
+
+    private val json = Json { ignoreUnknownKeys = true }
+
+    @Test
+    fun testSerialization() {
+        val request = StreamingSyncRequest(
+            buckets = listOf(BucketRequest("table1", "op1"), BucketRequest("table2", "op2")),
+            includeChecksum = true,
+            clientId = "client123",
+            parameters = JsonObject(mapOf("param1" to JsonPrimitive("value1")))
+        )
+
+        val serialized = json.encodeToString(request)
+
+        val expected = """
+            {"buckets":[{"name":"table1","after":"op1"},{"name":"table2","after":"op2"}],"client_id":"client123","parameters":{"param1":"value1"}}
+        """.trimIndent().replace("\n", "")
+
+        assertEquals(expected, serialized)
+    }
+
+    @Test
+    fun testDeserialization() {
+        val jsonString = """
+            {
+                "buckets": [{"name": "table1", "after": "op1"}, {"name": "table2", "after": "op2"}],
+                "include_checksum": false,
+                "client_id": "client456",
+                "parameters": {"param2": "value2"},
+                "raw_data": true
+            }
+        """.trimIndent()
+
+        val deserialized = json.decodeFromString<StreamingSyncRequest>(jsonString)
+
+        assertEquals(2, deserialized.buckets.size)
+        assertEquals("table1", deserialized.buckets[0].name)
+        assertEquals("op1", deserialized.buckets[0].after)
+        assertEquals("table2", deserialized.buckets[1].name)
+        assertEquals("op2", deserialized.buckets[1].after)
+        assertFalse(deserialized.includeChecksum)
+        assertEquals("client456", deserialized.clientId)
+        assertEquals(JsonPrimitive("value2"), deserialized.parameters?.get("param2"))
+    }
+
+    @Test
+    fun testDefaultValues() {
+        val request = StreamingSyncRequest(
+            buckets = listOf(),
+            clientId = "client789"
+        )
+
+        assertTrue(request.includeChecksum)
+        assertEquals(request.parameters, JsonObject(mapOf()))
+
+        val serialized = json.encodeToString(request)
+        val expected = """
+            {"buckets":[],"client_id":"client789"}
+        """.trimIndent().replace("\n", "")
+        assertEquals(serialized, expected)
+    }
+}
\ No newline at end of file
diff --git a/demos/supabase-todolist/gradle/libs.versions.toml b/demos/supabase-todolist/gradle/libs.versions.toml
index 0a593a82..aee29116 100644
--- a/demos/supabase-todolist/gradle/libs.versions.toml
+++ b/demos/supabase-todolist/gradle/libs.versions.toml
@@ -6,7 +6,7 @@ android-compileSdk = "34"
 java = "17"
 
 # Dependencies
-powersync-core = "0.1.6"
+powersync-core = "0.2.1"
 
 kotlin = "1.9.23"
 coroutines = "1.8.0"
diff --git a/demos/supabase-todolist/iosApp/iosApp.xcodeproj/project.pbxproj b/demos/supabase-todolist/iosApp/iosApp.xcodeproj/project.pbxproj
index d94ab97a..58344074 100644
--- a/demos/supabase-todolist/iosApp/iosApp.xcodeproj/project.pbxproj
+++ b/demos/supabase-todolist/iosApp/iosApp.xcodeproj/project.pbxproj
@@ -118,7 +118,6 @@
 				7555FF79242A565900829871 /* Resources */,
 				F85CB1118929364A9C6EFABC /* Frameworks */,
 				3C5ACF3A4AAFF294B2A5839B /* [CP] Embed Pods Frameworks */,
-				3114824168D992F9E0D6D9F4 /* [CP] Copy Pods Resources */,
 			);
 			buildRules = (
 			);
@@ -193,23 +192,6 @@
 			shellPath = /bin/sh;
 			shellScript = "cd \"$SRCROOT/..\"\n./gradlew :shared:embedAndSignAppleFrameworkForXcode\n";
 		};
-		3114824168D992F9E0D6D9F4 /* [CP] Copy Pods Resources */ = {
-			isa = PBXShellScriptBuildPhase;
-			buildActionMask = 2147483647;
-			files = (
-			);
-			inputFileListPaths = (
-				"${PODS_ROOT}/Target Support Files/Pods-iosApp/Pods-iosApp-resources-${CONFIGURATION}-input-files.xcfilelist",
-			);
-			name = "[CP] Copy Pods Resources";
-			outputFileListPaths = (
-				"${PODS_ROOT}/Target Support Files/Pods-iosApp/Pods-iosApp-resources-${CONFIGURATION}-output-files.xcfilelist",
-			);
-			runOnlyForDeploymentPostprocessing = 0;
-			shellPath = /bin/sh;
-			shellScript = "\"${PODS_ROOT}/Target Support Files/Pods-iosApp/Pods-iosApp-resources.sh\"\n";
-			showEnvVarsInLog = 0;
-		};
 		3C5ACF3A4AAFF294B2A5839B /* [CP] Embed Pods Frameworks */ = {
 			isa = PBXShellScriptBuildPhase;
 			buildActionMask = 2147483647;
diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index a293fa11..9c5d09b6 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -9,13 +9,13 @@ idea = "222.4459.24" # Flamingo | 2022.2.1 (see https://plugins.jetbrains.com/do
 
 # Dependencies
 kermit = "2.0.4"
-kotlin = "1.9.23"
+kotlin = "1.9.24"
 coroutines = "1.8.0"
 kotlinx-datetime = "0.5.0"
 kotlinx-io = "0.3.0"
 ktor = "2.3.10"
 uuid = "0.8.2"
-powersync-core = "0.1.6"
+powersync-core = "0.2.1"
 sqlite-android = "3.45.0"
 
 sqlDelight = "2.0.2"