diff --git a/testing/node-driver/src/main/kotlin/net/corda/testing/node/MockNetwork.kt b/testing/node-driver/src/main/kotlin/net/corda/testing/node/MockNetwork.kt
index 98964f3b94..6ae9732550 100644
--- a/testing/node-driver/src/main/kotlin/net/corda/testing/node/MockNetwork.kt
+++ b/testing/node-driver/src/main/kotlin/net/corda/testing/node/MockNetwork.kt
@@ -104,6 +104,7 @@ data class MockNetworkParameters(
     fun withServicePeerAllocationStrategy(servicePeerAllocationStrategy: InMemoryMessagingNetwork.ServicePeerAllocationStrategy): MockNetworkParameters {
         return copy(servicePeerAllocationStrategy = servicePeerAllocationStrategy)
     }
+
     fun withNotarySpecs(notarySpecs: List<MockNetworkNotarySpec>): MockNetworkParameters = copy(notarySpecs = notarySpecs)
     fun withCordappsForAllNodes(cordappsForAllNodes: Collection<TestCordapp>): MockNetworkParameters = copy(cordappsForAllNodes = cordappsForAllNodes)
 
@@ -125,7 +126,13 @@ data class MockNetworkParameters(
  * @property validating Boolean for whether the notary is validating or non-validating.
  * @property className String the optional name of a notary service class to load. If null, a builtin notary is loaded.
  */
-data class MockNetworkNotarySpec @JvmOverloads constructor(val name: CordaX500Name, val validating: Boolean = true, val className: String? = null)
+data class MockNetworkNotarySpec @JvmOverloads constructor(val name: CordaX500Name, val validating: Boolean = true) {
+    var className: String? = null
+
+    constructor(name: CordaX500Name, validating: Boolean = true, className: String? = null) : this(name, validating) {
+        this.className = className
+    }
+}
 
 /** A class that represents an unstarted mock node for testing. */
 class UnstartedMockNode private constructor(private val node: InternalMockNetwork.MockNode) {
diff --git a/testing/node-driver/src/main/kotlin/net/corda/testing/node/internal/InternalMockNetwork.kt b/testing/node-driver/src/main/kotlin/net/corda/testing/node/internal/InternalMockNetwork.kt
index 03f2bffdaf..3d0c786651 100644
--- a/testing/node-driver/src/main/kotlin/net/corda/testing/node/internal/InternalMockNetwork.kt
+++ b/testing/node-driver/src/main/kotlin/net/corda/testing/node/internal/InternalMockNetwork.kt
@@ -249,10 +249,10 @@ open class InternalMockNetwork(cordappPackages: List<String> = emptyList(),
 
     @VisibleForTesting
     internal open fun createNotaries(): List<TestStartedNode> {
-        return notarySpecs.map { (name, validating, className) ->
+        return notarySpecs.map { spec ->
             createNode(InternalMockNodeParameters(
-                    legalName = name,
-                    configOverrides = { doReturn(NotaryConfig(validating, className = className)).whenever(it).notary }
+                    legalName = spec.name,
+                    configOverrides = { doReturn(NotaryConfig(spec.validating, className = spec.className)).whenever(it).notary }
             ))
         }
     }