diff --git a/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/Action.kt b/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/Action.kt
index d55fac7b..228522dc 100644
--- a/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/Action.kt
+++ b/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/Action.kt
@@ -41,7 +41,7 @@ infix fun <T : Any, I : Any, R : Any> Action<T, I>.then(action: Action<I, R>): A
 // */
 //class PipeAction<in T : Any, out R : Any>(val transform: (Name, Data<T>, Meta) -> Data<R>?) : Action<T, R> {
 //    override fun invoke(node: DataNode<T>, meta: Meta): DataNode<R> = DataNode.build {
-//        node.dataSequence().forEach { (name, data) ->
+//        node.data().forEach { (name, data) ->
 //            val res = transform(name, data, meta)
 //            if (res != null) {
 //                set(name, res)
diff --git a/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/Data.kt b/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/Data.kt
index 058916b8..20957824 100644
--- a/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/Data.kt
+++ b/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/Data.kt
@@ -3,7 +3,6 @@ package hep.dataforge.data
 import hep.dataforge.meta.Meta
 import hep.dataforge.meta.MetaRepr
 import kotlinx.coroutines.CoroutineScope
-import kotlin.coroutines.CoroutineContext
 import kotlin.reflect.KClass
 
 /**
@@ -30,7 +29,9 @@ interface Data<out T : Any> : MetaRepr {
         const val TYPE = "data"
 
         fun <T : Any> of(type: KClass<out T>, goal: Goal<T>, meta: Meta): Data<T> = DataImpl(type, goal, meta)
+
         inline fun <reified T : Any> of(goal: Goal<T>, meta: Meta): Data<T> = of(T::class, goal, meta)
+
         fun <T : Any> of(name: String, type: KClass<out T>, goal: Goal<T>, meta: Meta): Data<T> =
             NamedData(name, of(type, goal, meta))
 
@@ -42,7 +43,18 @@ interface Data<out T : Any> : MetaRepr {
     }
 }
 
-suspend fun <T: Any> Data<T>.await(): T = goal.await()
+/**
+ * Upcast a [Data] to a supertype
+ */
+inline fun <reified R : Any, reified T : R> Data<T>.cast(): Data<R> {
+    return Data.of(R::class, goal, meta)
+}
+
+fun <R : Any, T : R> Data<T>.cast(type: KClass<R>): Data<R> {
+    return Data.of(type, goal, meta)
+}
+
+suspend fun <T : Any> Data<T>.await(): T = goal.await()
 
 /**
  * Generic Data implementation
diff --git a/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/DataFilter.kt b/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/DataFilter.kt
index 79f1aacc..b5a40513 100644
--- a/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/DataFilter.kt
+++ b/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/DataFilter.kt
@@ -23,7 +23,7 @@ fun <T : Any> DataNode<T>.filter(filter: DataFilter): DataNode<T> {
     val sourceNode = filter.from?.let { getNode(it.toName()) } ?: this@filter
     val regex = filter.pattern.toRegex()
     val targetNode = DataTreeBuilder(type).apply {
-        sourceNode.dataSequence().forEach { (name, data) ->
+        sourceNode.data().forEach { (name, data) ->
             if (name.toString().matches(regex)) {
                 this[name] = data
             }
diff --git a/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/DataNode.kt b/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/DataNode.kt
index dc71c28c..3d4b2638 100644
--- a/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/DataNode.kt
+++ b/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/DataNode.kt
@@ -26,14 +26,14 @@ interface DataNode<out T : Any> {
     /**
      * Walk the tree upside down and provide all data nodes with full names
      */
-    fun dataSequence(): Sequence<Pair<Name, Data<T>>>
+    fun data(): Sequence<Pair<Name, Data<T>>>
 
     /**
      * A sequence of all nodes in the tree walking upside down, excluding self
      */
-    fun nodeSequence(): Sequence<Pair<Name, DataNode<T>>>
+    fun nodes(): Sequence<Pair<Name, DataNode<T>>>
 
-    operator fun iterator(): Iterator<Pair<Name, Data<T>>> = dataSequence().iterator()
+    operator fun iterator(): Iterator<Pair<Name, Data<T>>> = data().iterator()
 
     companion object {
         const val TYPE = "dataNode"
@@ -43,7 +43,6 @@ interface DataNode<out T : Any> {
 
         fun <T : Any> builder(type: KClass<out T>) = DataTreeBuilder(type)
     }
-
 }
 
 internal sealed class DataTreeItem<out T : Any> {
@@ -69,14 +68,14 @@ class DataTree<out T : Any> internal constructor(
         else -> getNode(name.first()!!.asName())?.getNode(name.cutFirst())
     }
 
-    override fun dataSequence(): Sequence<Pair<Name, Data<T>>> {
+    override fun data(): Sequence<Pair<Name, Data<T>>> {
         return sequence {
             items.forEach { (head, tree) ->
                 when (tree) {
                     is DataTreeItem.Value -> yield(head.asName() to tree.value)
                     is DataTreeItem.Node -> {
                         val subSequence =
-                            tree.tree.dataSequence().map { (name, data) -> (head.asName() + name) to data }
+                            tree.tree.data().map { (name, data) -> (head.asName() + name) to data }
                         yieldAll(subSequence)
                     }
                 }
@@ -84,13 +83,13 @@ class DataTree<out T : Any> internal constructor(
         }
     }
 
-    override fun nodeSequence(): Sequence<Pair<Name, DataNode<T>>> {
+    override fun nodes(): Sequence<Pair<Name, DataNode<T>>> {
         return sequence {
             items.forEach { (head, tree) ->
                 if (tree is DataTreeItem.Node) {
                     yield(head.asName() to tree.tree)
                     val subSequence =
-                        tree.tree.nodeSequence().map { (name, node) -> (head.asName() + name) to node }
+                        tree.tree.nodes().map { (name, node) -> (head.asName() + name) to node }
                     yieldAll(subSequence)
                 }
             }
@@ -183,16 +182,16 @@ class DataTreeBuilder<T : Any>(private val type: KClass<out T>) {
  * Generate a mutable builder from this node. Node content is not changed
  */
 fun <T : Any> DataNode<T>.builder(): DataTreeBuilder<T> = DataTreeBuilder(type).apply {
-    dataSequence().forEach { (name, data) -> this[name] = data }
+    data().forEach { (name, data) -> this[name] = data }
 }
 
 /**
  * Start computation for all goals in data node
  */
-fun DataNode<*>.startAll() = dataSequence().forEach { (_, data) -> data.goal.start() }
+fun DataNode<*>.startAll() = data().forEach { (_, data) -> data.goal.start() }
 
 fun <T : Any> DataNode<T>.filter(predicate: (Name, Data<T>) -> Boolean): DataNode<T> = DataNode.build(type) {
-    dataSequence().forEach { (name, data) ->
+    data().forEach { (name, data) ->
         if (predicate(name, data)) {
             this[name] = data
         }
diff --git a/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/Goal.kt b/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/Goal.kt
index 738f7dbc..991ddbdb 100644
--- a/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/Goal.kt
+++ b/dataforge-data/src/commonMain/kotlin/hep/dataforge/data/Goal.kt
@@ -112,7 +112,20 @@ fun <T, R> Collection<Goal<T>>.join(
     scope: CoroutineScope = first(),
     context: CoroutineContext = EmptyCoroutineContext,
     block: suspend CoroutineScope.(Collection<T>) -> R
-): Goal<R> =
-    scope.createGoal(this, context) {
-        block(map { it.await() })
-    }
\ No newline at end of file
+): Goal<R> = scope.createGoal(this, context) {
+    block(map { it.await() })
+}
+
+/**
+ * A joining goal for a map
+ * @param K type of the map key
+ * @param T type of the input goal
+ * @param R type of the result goal
+ */
+fun <K, T, R> Map<K, Goal<T>>.join(
+    scope: CoroutineScope = values.first(),
+    context: CoroutineContext = EmptyCoroutineContext,
+    block: suspend CoroutineScope.(Map<K, T>) -> R
+): Goal<R> = scope.createGoal(this.values, context) {
+    block(mapValues { it.value.await() })
+}
\ No newline at end of file
diff --git a/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/CheckedDataNode.kt b/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/CheckedDataNode.kt
new file mode 100644
index 00000000..980bb474
--- /dev/null
+++ b/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/CheckedDataNode.kt
@@ -0,0 +1,46 @@
+package hep.dataforge.data
+
+import hep.dataforge.names.Name
+import kotlin.reflect.KClass
+import kotlin.reflect.full.isSubclassOf
+
+fun <T : Any, R : Any> Data<T>.safeCast(type: KClass<R>): Data<R>? {
+    return if (type.isSubclassOf(type)) {
+        @Suppress("UNCHECKED_CAST")
+        Data.of(type, goal as Goal<R>, meta)
+    } else {
+        null
+    }
+}
+
+/**
+ * Filter a node by data and node type. Resulting node and its subnodes is guaranteed to have border type [type],
+ * but could contain empty nodes
+ */
+fun <T : Any, R : Any> DataNode<T>.cast(type: KClass<out R>): DataNode<R> {
+    return if (this is CheckedDataNode) {
+        origin.cast(type)
+    } else {
+        CheckedDataNode(this, type)
+    }
+}
+
+inline fun <T : Any, reified R : Any> DataNode<T>.cast(): DataNode<R> = cast(R::class)
+
+class CheckedDataNode<out T : Any>(val origin: DataNode<Any>, override val type: KClass<out T>) : DataNode<T> {
+
+    override fun get(name: Name): Data<T>? =
+        origin[name]?.safeCast(type)
+
+    override fun getNode(name: Name): DataNode<T>? {
+        return origin.getNode(name)?.cast(type)
+    }
+
+    override fun data(): Sequence<Pair<Name, Data<T>>> =
+        origin.data().mapNotNull { pair ->
+            pair.second.safeCast(type)?.let { pair.first to it }
+        }
+
+    override fun nodes(): Sequence<Pair<Name, DataNode<T>>> =
+        origin.nodes().map { it.first to it.second.cast(type) }
+}
\ No newline at end of file
diff --git a/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/GroupBuilder.kt b/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/GroupBuilder.kt
index a47dd4c6..68e9e092 100644
--- a/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/GroupBuilder.kt
+++ b/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/GroupBuilder.kt
@@ -44,7 +44,7 @@ object GroupBuilder {
         override fun <T : Any> invoke(node: DataNode<T>): Map<String, DataNode<T>> {
             val map = HashMap<String, DataTreeBuilder<T>>()
 
-            node.dataSequence().forEach { (name, data) ->
+            node.data().forEach { (name, data) ->
                 val tagValue = data.meta[key]?.string ?: defaultTagValue
                 map.getOrPut(tagValue) { DataNode.builder(node.type) }[name] = data
             }
diff --git a/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/JoinAction.kt b/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/JoinAction.kt
index 3d200a14..d8702735 100644
--- a/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/JoinAction.kt
+++ b/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/JoinAction.kt
@@ -6,7 +6,6 @@ import hep.dataforge.meta.MetaBuilder
 import hep.dataforge.meta.builder
 import hep.dataforge.names.Name
 import hep.dataforge.names.toName
-import java.util.stream.Collectors
 import kotlin.coroutines.CoroutineContext
 import kotlin.coroutines.EmptyCoroutineContext
 import kotlin.reflect.KClass
@@ -17,9 +16,9 @@ class JoinGroup<T : Any, R : Any>(var name: String, internal val node: DataNode<
 
     var meta: MetaBuilder = MetaBuilder()
 
-    lateinit var result: suspend ActionEnv.(Map<String, T>) -> R
+    lateinit var result: suspend ActionEnv.(Map<Name, T>) -> R
 
-    fun result(f: suspend ActionEnv.(Map<String, T>) -> R) {
+    fun result(f: suspend ActionEnv.(Map<Name, T>) -> R) {
         this.result = f;
     }
 
@@ -53,7 +52,7 @@ class JoinGroupBuilder<T : Any, R : Any> {
     /**
      * Apply transformation to the whole node
      */
-    fun result(resultName: String, f: suspend ActionEnv.(Map<String, T>) -> R) {
+    fun result(resultName: String, f: suspend ActionEnv.(Map<Name, T>) -> R) {
         groupRules += { node ->
             listOf(JoinGroup<T, R>(resultName, node).apply { result(f) })
         }
@@ -85,21 +84,19 @@ class JoinAction<T : Any, R : Any>(
 
                 val laminate = Laminate(group.meta, meta)
 
-                val goalMap: Map<String, Goal<T>> = group.node
-                    .dataSequence()
+                val goalMap: Map<Name, Goal<T>> = group.node
+                    .data()
                     .associate { it.first to it.second.goal }
 
                 val groupName: String = group.name;
 
-                if (groupName.isEmpty()) {
-                    throw AnonymousNotAlowedException("Anonymous groups are not allowed");
-                }
-
                 val env = ActionEnv(groupName.toName(), laminate.builder())
 
-                val goal = goalMap.join(dispatcher) { group.result.invoke(env, it) }
-                val res = NamedData(env.name, outputType, goal, env.meta)
-                builder.add(res)
+                val goal = goalMap.join(context = context) { group.result.invoke(env, it) }
+
+                val res = Data.of(outputType, goal, env.meta)
+
+                set(env.name, res)
             }
 
         }
diff --git a/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/PipeAction.kt b/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/PipeAction.kt
index b52830d3..933c546d 100644
--- a/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/PipeAction.kt
+++ b/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/PipeAction.kt
@@ -25,7 +25,7 @@ class PipeBuilder<T, R>(var name: Name, var meta: MetaBuilder) {
 }
 
 
-abstract class PipeAction<T : Any, R : Any>(
+class PipeAction<T : Any, R : Any>(
     val inputType: KClass<T>,
     val outputType: KClass<R>,
     val context: CoroutineContext = EmptyCoroutineContext,
@@ -37,7 +37,7 @@ abstract class PipeAction<T : Any, R : Any>(
             error("$inputType expected, but ${node.type} received")
         }
         return DataNode.build(outputType) {
-            node.dataSequence().forEach { (name, data) ->
+            node.data().forEach { (name, data) ->
                 //merging data meta with action meta (data meta is primary)
                 val oldMeta = meta.builder().apply { update(data.meta) }
                 // creating environment from old meta and name
@@ -57,4 +57,11 @@ abstract class PipeAction<T : Any, R : Any>(
     }
 }
 
+inline fun <reified T : Any, reified R : Any> DataNode<T>.pipe(
+    meta: Meta,
+    context: CoroutineContext = EmptyCoroutineContext,
+    noinline action: PipeBuilder<T, R>.() -> Unit
+): DataNode<R> = PipeAction(T::class, R::class, context, action).invoke(this, meta)
+
+
 
diff --git a/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/SplitAction.kt b/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/SplitAction.kt
index 880c065f..a9029590 100644
--- a/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/SplitAction.kt
+++ b/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/SplitAction.kt
@@ -3,11 +3,17 @@ package hep.dataforge.data
 import hep.dataforge.meta.Laminate
 import hep.dataforge.meta.Meta
 import hep.dataforge.meta.MetaBuilder
+import hep.dataforge.meta.builder
 import hep.dataforge.names.Name
-import kotlinx.coroutines.runBlocking
+import hep.dataforge.names.toName
+import kotlin.collections.set
+import kotlin.coroutines.CoroutineContext
+import kotlin.coroutines.EmptyCoroutineContext
+import kotlin.reflect.KClass
+import kotlin.reflect.full.isSuperclassOf
 
 
-class FragmentEnv<T : Any, R : Any>(val context: Context, val name: String, var meta: MetaBuilder, val log: Chronicle) {
+class FragmentRule<T : Any, R : Any>(val name: Name, var meta: MetaBuilder) {
     lateinit var result: suspend (T) -> R
 
     fun result(f: suspend (T) -> R) {
@@ -16,75 +22,51 @@ class FragmentEnv<T : Any, R : Any>(val context: Context, val name: String, var
 }
 
 
-class SplitBuilder<T : Any, R : Any>(val context: Context, val name: String, val meta: Meta) {
-    internal val fragments: MutableMap<String, FragmentEnv<T, R>.() -> Unit> = HashMap()
+class SplitBuilder<T : Any, R : Any>(val name: Name, val meta: Meta) {
+    internal val fragments: MutableMap<Name, FragmentRule<T, R>.() -> Unit> = HashMap()
 
     /**
      * Add new fragment building rule. If the framgent not defined, result won't be available even if it is present in the map
      * @param name the name of a fragment
      * @param rule the rule to transform fragment name and meta using
      */
-    fun fragment(name: String, rule: FragmentEnv<T, R>.() -> Unit) {
-        fragments[name] = rule
+    fun fragment(name: String, rule: FragmentRule<T, R>.() -> Unit) {
+        fragments[name.toName()] = rule
     }
 }
 
-class KSplit<T : Any, R : Any>(
-    actionName: String,
-    inputType: Class<T>,
-    outputType: Class<R>,
+class SplitAction<T : Any, R : Any>(
+    val inputType: KClass<T>,
+    val outputType: KClass<R>,
+    val context: CoroutineContext = EmptyCoroutineContext,
     private val action: SplitBuilder<T, R>.() -> Unit
-) : GenericAction<T, R>(actionName, inputType, outputType) {
+) : Action<T, R> {
 
-    override fun run(context: Context, data: DataNode<out T>, actionMeta: Meta): DataNode<R> {
-        if (!this.inputType.isAssignableFrom(data.type)) {
-            throw RuntimeException("Type mismatch in action $name. $inputType expected, but ${data.type} received")
+    override fun invoke(node: DataNode<T>, meta: Meta): DataNode<R> {
+        if (!this.inputType.isSuperclassOf(node.type)) {
+            error("$inputType expected, but ${node.type} received")
         }
 
-        val builder = DataSet.edit(outputType)
+        return DataNode.build(outputType) {
+            node.data().forEach { (name, data) ->
 
+                val laminate = Laminate(data.meta, meta)
 
-        runBlocking {
-            data.dataStream(true).forEach {
+                val split = SplitBuilder<T, R>(name, data.meta).apply(action)
 
-                val laminate = Laminate(it.meta, actionMeta)
-
-                val split = SplitBuilder<T, R>(context, it.name, it.meta).apply(action)
-
-
-                val dispatcher = context + getExecutorService(context, laminate).asCoroutineDispatcher()
-
-                // Create a map of results in a single goal
-                //val commonGoal = it.goal.pipe(dispatcher) { split.result.invoke(env, it) }
 
                 // apply individual fragment rules to result
-                split.fragments.forEach { name, rule ->
-                    val env = FragmentEnv<T, R>(
-                        context,
-                        it.name,
-                        laminate.builder,
-                        context.history.getChronicle(Name.joinString(it.name, name))
-                    )
+                split.fragments.forEach { fragmentName, rule ->
+                    val env = FragmentRule<T, R>(fragmentName, laminate.builder())
 
-                    rule.invoke(env)
+                    rule(env)
 
-                    val goal = it.goal.pipe(dispatcher, env.result)
+                    val goal = data.goal.pipe(context = context) { env.result(it) }
 
-                    val res = NamedData(env.name, outputType, goal, env.meta)
-                    builder.add(res)
+                    val res = Data.of(outputType, goal, env.meta)
+                    set(env.name, res)
                 }
             }
         }
-
-        return builder.build();
     }
-}
-
-inline fun <reified T : Any, reified R : Any> DataNode<T>.pipe(
-    context: Context,
-    meta: Meta,
-    name: String = "pipe",
-    noinline action: PipeBuilder<T, R>.() -> Unit
-): DataNode<R> {
-    return KPipe(name, T::class.java, R::class.java, action).run(context, this, meta);
 }
\ No newline at end of file
diff --git a/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/data.kt b/dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/_Data.kt
similarity index 100%
rename from dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/data.kt
rename to dataforge-data/src/jvmMain/kotlin/hep/dataforge/data/_Data.kt
diff --git a/dataforge-meta/src/commonMain/kotlin/hep/dataforge/meta/Specification.kt b/dataforge-meta/src/commonMain/kotlin/hep/dataforge/meta/Specification.kt
index a578b119..e1ed91fe 100644
--- a/dataforge-meta/src/commonMain/kotlin/hep/dataforge/meta/Specification.kt
+++ b/dataforge-meta/src/commonMain/kotlin/hep/dataforge/meta/Specification.kt
@@ -22,13 +22,14 @@ interface SpecificationCompanion<T : Specification> {
 
     fun build(action: T.() -> Unit) = update(Config(), action)
 
+    fun empty() = build {  }
+
     /**
      * Wrap generic configuration producing instance of desired type
      */
     fun wrap(config: Config): T
 
     fun wrap(meta: Meta): T = wrap(meta.toConfig())
-
 }
 
 fun <T : Specification> specification(wrapper: (Config) -> T): SpecificationCompanion<T> =
diff --git a/dataforge-workspace/src/commonMain/kotlin/hep/dataforge/workspace/Dependency.kt b/dataforge-workspace/src/commonMain/kotlin/hep/dataforge/workspace/Dependency.kt
index 1f0f64f4..7d87cc58 100644
--- a/dataforge-workspace/src/commonMain/kotlin/hep/dataforge/workspace/Dependency.kt
+++ b/dataforge-workspace/src/commonMain/kotlin/hep/dataforge/workspace/Dependency.kt
@@ -37,7 +37,7 @@ class TaskModelDependency(val name: String, val meta: Meta, val placement: Name
         return if (placement.isEmpty()) {
             result
         } else {
-            DataTreeBuilder<Any>().apply { this[placement] = result }.build()
+            DataTreeBuilder(Any::class).apply { this[placement] = result }.build()
         }
     }
 
diff --git a/dataforge-workspace/src/commonMain/kotlin/hep/dataforge/workspace/TaskModel.kt b/dataforge-workspace/src/commonMain/kotlin/hep/dataforge/workspace/TaskModel.kt
index 8d0de0c0..1f7771c6 100644
--- a/dataforge-workspace/src/commonMain/kotlin/hep/dataforge/workspace/TaskModel.kt
+++ b/dataforge-workspace/src/commonMain/kotlin/hep/dataforge/workspace/TaskModel.kt
@@ -45,8 +45,8 @@ data class TaskModel(
  * Build input for the task
  */
 fun TaskModel.buildInput(workspace: Workspace): DataTree<Any> {
-    return DataTreeBuilder<Any>().apply {
-        dependencies.asSequence().flatMap { it.apply(workspace).dataSequence() }.forEach { (name, data) ->
+    return DataTreeBuilder(Any::class).apply {
+        dependencies.asSequence().flatMap { it.apply(workspace).data() }.forEach { (name, data) ->
             //TODO add concise error on replacement
             this[name] = data
         }
diff --git a/dataforge-workspace/src/commonMain/kotlin/hep/dataforge/workspace/Workspace.kt b/dataforge-workspace/src/commonMain/kotlin/hep/dataforge/workspace/Workspace.kt
index 40c45aaf..e9a2914d 100644
--- a/dataforge-workspace/src/commonMain/kotlin/hep/dataforge/workspace/Workspace.kt
+++ b/dataforge-workspace/src/commonMain/kotlin/hep/dataforge/workspace/Workspace.kt
@@ -43,8 +43,8 @@ interface Workspace : ContextAware, Provider {
         return when (target) {
             "target", Meta.TYPE -> targets.keys.asSequence().map { it.toName() }
             Task.TYPE -> tasks.keys.asSequence().map { it.toName() }
-            Data.TYPE -> data.dataSequence().map { it.first }
-            DataNode.TYPE -> data.nodeSequence().map { it.first }
+            Data.TYPE -> data.data().map { it.first }
+            DataNode.TYPE -> data.nodes().map { it.first }
             else -> emptySequence()
         }
     }
diff --git a/dataforge-workspace/src/commonMain/kotlin/hep/dataforge/workspace/WorkspaceBuilder.kt b/dataforge-workspace/src/commonMain/kotlin/hep/dataforge/workspace/WorkspaceBuilder.kt
index 9aebdcd0..9f8eb08f 100644
--- a/dataforge-workspace/src/commonMain/kotlin/hep/dataforge/workspace/WorkspaceBuilder.kt
+++ b/dataforge-workspace/src/commonMain/kotlin/hep/dataforge/workspace/WorkspaceBuilder.kt
@@ -11,7 +11,7 @@ import hep.dataforge.meta.buildMeta
  * A builder for a workspace
  */
 class WorkspaceBuilder(var context: Context) {
-    val data = DataTreeBuilder<Any>()
+    val data = DataTreeBuilder(Any::class)
     val targets = HashMap<String, Meta>()
     val tasks = HashSet<Task<Any>>()
 
diff --git a/dataforge-workspace/src/jvmMain/kotlin/hep/dataforge/workspace/GenericTask.kt b/dataforge-workspace/src/jvmMain/kotlin/hep/dataforge/workspace/GenericTask.kt
new file mode 100644
index 00000000..b2d5967a
--- /dev/null
+++ b/dataforge-workspace/src/jvmMain/kotlin/hep/dataforge/workspace/GenericTask.kt
@@ -0,0 +1,218 @@
+package hep.dataforge.workspace
+
+import hep.dataforge.data.*
+import hep.dataforge.descriptors.NodeDescriptor
+import hep.dataforge.meta.Meta
+import hep.dataforge.meta.get
+import hep.dataforge.meta.node
+import hep.dataforge.names.toName
+import kotlin.reflect.KClass
+
+class GenericTask<R : Any>(
+    override val name: String,
+    override val type: KClass<out R>,
+    override val descriptor: NodeDescriptor,
+    private val modelTransform: TaskModelBuilder.(Meta) -> Unit,
+    private val dataTransform: TaskModel.(DataNode<Any>) -> DataNode<R>
+) : Task<R> {
+
+    private fun gather(workspace: Workspace, model: TaskModel): DataNode<Any> {
+//        val builder = DataTreeBuilder(Any::class)
+//        model.dependencies.forEach { dep ->
+//            dep.apply(workspace)
+//        }
+//        return builder.build()
+    }
+
+    override fun run(workspace: Workspace, model: TaskModel): DataNode<R> {
+        //validate model
+        validate(model)
+
+        // gather data
+        val input = gather(workspace, model)
+
+        //execute
+        workspace.context.logger.info("Starting task '$name' on data node ${input.name} with meta: \n${model.meta}")
+        val output = dataTransform.invoke(model, input)
+
+        //handle result
+        output.handle(model.context.dispatcher) { this.handle(it) }
+
+        return output
+    }
+
+    /**
+     * Build new TaskModel and apply specific model transformation for this
+     * task. By default model uses the meta node with the same node as the name of the task.
+     *
+     * @param workspace
+     * @param taskConfig
+     * @return
+     */
+    override fun build(workspace: Workspace, taskConfig: Meta): TaskModel {
+        val taskMeta = taskConfig[name]?.node ?: taskConfig
+        val builder = TaskModelBuilder(name, taskMeta)
+        modelTransform.invoke(builder, taskMeta)
+        return builder.build()
+    }
+    //TODO add validation
+}
+
+class KTaskBuilder(val name: String) {
+    private var modelTransform: TaskModelBuilder.(Meta) -> Unit = { data("*") }
+    var descriptor: NodeDescriptor? = null
+
+    private class DataTransformation(
+        val from: String = "",
+        val to: String = "",
+        val transform: TaskModel.(DataNode<Any>?) -> DataNode<Any>
+    ) {
+        operator fun invoke(model: TaskModel, node: DataNode<Any>): DataNode<Any> {
+            val localData = if (from.isEmpty()) {
+                node
+            } else {
+                node.getNode(from.toName())
+            }
+            return transform.invoke(model, localData);
+        }
+    }
+
+    private val dataTransforms: MutableList<DataTransformation> = ArrayList();
+
+    fun model(modelTransform: TaskModelBuilder.(Meta) -> Unit) {
+        this.modelTransform = modelTransform
+    }
+
+    fun <T : Any> transform(
+        inputType: Class<T>,
+        from: String = "",
+        to: String = "",
+        transform: TaskModel.(DataNode<T>) -> DataNode<Any>
+    ) {
+        dataTransforms += DataTransformation(from, to) { data: DataNode<Any> ->
+            transform.invoke(this, data.checked(inputType))
+        }
+    }
+
+    inline fun <reified T : Any> transform(
+        from: String = "",
+        to: String = "",
+        noinline transform: TaskModel.(DataNode<T>) -> DataNode<Any>
+    ) {
+        transform(T::class.java, from, to, transform)
+    }
+
+    /**
+     * Perform given action on data elements in `from` node in input and put the result to `to` node
+     */
+    inline fun <reified T : Any, reified R : Any> action(action: Action<T, R>, from: String = "", to: String = "") {
+        transform(from, to) { data: DataNode<T> ->
+            action(data, meta)
+        }
+    }
+
+    inline fun <reified T : Any, reified R : Any> pipeAction(
+        actionName: String = "pipe",
+        from: String = "",
+        to: String = "",
+        noinline action: PipeBuilder<T, R>.() -> Unit
+    ) {
+        val pipe: Action<T, R> = PipeAction(
+            inputType = T::class,
+            outputType = R::class,
+            block = action
+        )
+        action(pipe, from, to);
+    }
+
+    inline fun <reified T : Any, reified R : Any> pipe(
+        actionName: String = "pipe",
+        from: String = "",
+        to: String = "",
+        noinline action: suspend ActionEnv.(T) -> R
+    ) {
+        val pipe: Action<T, R> = PipeAction(
+            inputType = T::class,
+            outputType = R::class
+        ) { result(action) }
+        action(pipe, from, to);
+    }
+
+
+    inline fun <reified T : Any, reified R : Any> joinAction(
+        actionName: String = "join",
+        from: String = "",
+        to: String = "",
+        noinline action: JoinGroupBuilder<T, R>.() -> Unit
+    ) {
+        val join: Action<T, R> = JoinAction(
+            inputType = T::class,
+            outputType = R::class,
+            action = action
+        )
+        action(join, from, to);
+    }
+
+    inline fun <reified T : Any, reified R : Any> join(
+        actionName: String = name,
+        from: String = "",
+        to: String = "",
+        noinline action: suspend ActionEnv.(Map<String, T>) -> R
+    ) {
+        val join: Action<T, R> = JoinAction(
+            inputType = T::class,
+            outputType = R::class,
+            action = {
+                result(meta.getString("@target", actionName), action)
+            }
+        )
+        action(join, from, to);
+    }
+
+    inline fun <reified T : Any, reified R : Any> splitAction(
+        actionName: String = "split",
+        from: String = "",
+        to: String = "",
+        noinline action: SplitBuilder<T, R>.() -> Unit
+    ) {
+        val split: Action<T, R> = SplitAction(
+            inputType = T::class,
+            outputType = R::class,
+            action = action
+        )
+        action(split, from, to);
+    }
+
+    /**
+     * Use DSL to create a descriptor for this task
+     */
+    fun descriptor(transform: NodeDescriptor.() -> Unit) {
+        this.descriptor = NodeDescriptor.build(transform)
+    }
+
+    fun build(): GenericTask<Any> {
+        val transform: TaskModel.(DataNode<Any>) -> DataNode<Any> = { data ->
+            if (dataTransforms.isEmpty()) {
+                //return data node as is
+                logger.warn("No transformation present, returning input data")
+                data.checked(Any::class.java)
+            } else {
+                val builder = DataTreeBuilder(Any::class)
+                dataTransforms.forEach {
+                    val res = it(this, data)
+                    if (it.to.isEmpty()) {
+                        builder.update(res)
+                    } else {
+                        builder.putNode(it.to, res)
+                    }
+                }
+                builder.build()
+            }
+        }
+        return GenericTask<Any>(name, Any::class, descriptor ?: NodeDescriptor.empty(), modelTransform, transform);
+    }
+}
+
+fun task(name: String, builder: KTaskBuilder.() -> Unit): GenericTask<Any> {
+    return KTaskBuilder(name).apply(builder).build();
+}
\ No newline at end of file
diff --git a/dataforge-workspace/src/jvmMain/kotlin/hep/dataforge/workspace/KTask.kt b/dataforge-workspace/src/jvmMain/kotlin/hep/dataforge/workspace/KTask.kt
deleted file mode 100644
index 7717e9ec..00000000
--- a/dataforge-workspace/src/jvmMain/kotlin/hep/dataforge/workspace/KTask.kt
+++ /dev/null
@@ -1,180 +0,0 @@
-package hep.dataforge.workspace
-
-import hep.dataforge.data.Action
-import hep.dataforge.data.DataNode
-import hep.dataforge.data.DataTree
-import hep.dataforge.descriptors.NodeDescriptor
-import hep.dataforge.meta.Meta
-import hep.dataforge.names.Name
-import kotlin.reflect.KClass
-
-class KTask<R : Any>(
-    override val name: String,
-    type: KClass<R>,
-    descriptor: NodeDescriptor? = null,
-    private val modelTransform: TaskModel.Builder.(Meta) -> Unit,
-    private val dataTransform: TaskModel.(DataNode<Any>) -> DataNode<R>
-) : AbstractTask<R>(type.java, descriptor) {
-
-    override fun run(model: TaskModel, data: DataNode<Any>): DataNode<R> {
-        model.context.logger.info("Starting task '$name' on data node ${data.name} with meta: \n${model.meta}")
-        return dataTransform.invoke(model, data);
-    }
-
-    override fun buildModel(model: TaskModel.Builder, meta: Meta) {
-        modelTransform.invoke(model, meta);
-    }
-
-    //TODO add validation
-}
-
-class KTaskBuilder(val name: String) {
-    private var modelTransform: TaskModel.Builder.(Meta) -> Unit = { data("*") }
-    var descriptor: NodeDescriptor? = null
-
-    private class DataTransformation(
-        val from: String = "",
-        val to: String = "",
-        val transform: TaskModel.(DataNode<out Any>) -> DataNode<out Any>
-    ) {
-        operator fun invoke(model: TaskModel, node: DataNode<Any>): DataNode<out Any> {
-            val localData = if (from.isEmpty()) {
-                node
-            } else {
-                node.getNode(from)
-            }
-            return transform.invoke(model, localData);
-        }
-    }
-
-    private val dataTransforms: MutableList<DataTransformation> = ArrayList();
-
-    fun model(modelTransform: TaskModel.Builder.(Meta) -> Unit) {
-        this.modelTransform = modelTransform
-    }
-
-    fun <T : Any> transform(inputType: Class<T>, from: String = "", to: String = "", transform: TaskModel.(DataNode<out T>) -> DataNode<out Any>) {
-        dataTransforms += DataTransformation(from, to) { data: DataNode<out Any> ->
-            transform.invoke(this, data.checked(inputType))
-        }
-    }
-
-    inline fun <reified T : Any> transform(from: String = "", to: String = "", noinline transform: TaskModel.(DataNode<out T>) -> DataNode<out Any>) {
-        transform(T::class.java, from, to, transform)
-    }
-
-    /**
-     * Perform given action on data elements in `from` node in input and put the result to `to` node
-     */
-    inline fun <reified T : Any, reified R : Any> action(action: Action<T, R>, from: String = "", to: String = "") {
-        transform(from, to){ data: DataNode<out T> ->
-            action.run(context, data, meta)
-        }
-    }
-
-    inline fun <reified T : Any, reified R : Any> pipeAction(
-        actionName: String = "pipe",
-        from: String = "",
-        to: String = "",
-        noinline action: PipeBuilder<T, R>.() -> Unit) {
-        val pipe: Action<T, R> = KPipe(
-            actionName = Name.joinString(name, actionName),
-            inputType = T::class.java,
-            outputType = R::class.java,
-            action = action
-        )
-        action(pipe, from, to);
-    }
-
-    inline fun <reified T : Any, reified R : Any> pipe(
-        actionName: String = "pipe",
-        from: String = "",
-        to: String = "",
-        noinline action: suspend ActionEnv.(T) -> R) {
-        val pipe: Action<T, R> = KPipe(
-            actionName = Name.joinString(name, actionName),
-            inputType = T::class.java,
-            outputType = R::class.java,
-            action = { result(action) }
-        )
-        action(pipe, from, to);
-    }
-
-
-    inline fun <reified T : Any, reified R : Any> joinAction(
-        actionName: String = "join",
-        from: String = "",
-        to: String = "",
-        noinline action: JoinGroupBuilder<T, R>.() -> Unit) {
-        val join: Action<T, R> = KJoin(
-            actionName = Name.joinString(name, actionName),
-            inputType = T::class.java,
-            outputType = R::class.java,
-            action = action
-        )
-        action(join, from, to);
-    }
-
-    inline fun <reified T : Any, reified R : Any> join(
-        actionName: String = name,
-        from: String = "",
-        to: String = "",
-        noinline action: suspend ActionEnv.(Map<String, T>) -> R) {
-        val join: Action<T, R> = KJoin(
-            actionName = Name.joinString(name, actionName),
-            inputType = T::class.java,
-            outputType = R::class.java,
-            action = {
-                result(meta.getString("@target", actionName), action)
-            }
-        )
-        action(join, from, to);
-    }
-
-    inline fun <reified T : Any, reified R : Any> splitAction(
-        actionName: String = "split",
-        from: String = "",
-        to: String = "",
-        noinline action: SplitBuilder<T, R>.() -> Unit) {
-        val split: Action<T, R> = KSplit(
-            actionName = Name.joinString(name, actionName),
-            inputType = T::class.java,
-            outputType = R::class.java,
-            action = action
-        )
-        action(split, from, to);
-    }
-
-    /**
-     * Use DSL to create a descriptor for this task
-     */
-    fun descriptor(transform: DescriptorBuilder.() -> Unit) {
-        this.descriptor = DescriptorBuilder(name).apply(transform).build()
-    }
-
-    fun build(): KTask<Any> {
-        val transform: TaskModel.(DataNode<Any>) -> DataNode<Any> = { data ->
-            if (dataTransforms.isEmpty()) {
-                //return data node as is
-                logger.warn("No transformation present, returning input data")
-                data.checked(Any::class.java)
-            } else {
-                val builder: DataNodeEditor<Any> = DataTree.edit(Any::class.java)
-                dataTransforms.forEach {
-                    val res = it(this, data)
-                    if (it.to.isEmpty()) {
-                        builder.update(res)
-                    } else {
-                        builder.putNode(it.to, res)
-                    }
-                }
-                builder.build()
-            }
-        }
-        return KTask(name, Any::class, descriptor, modelTransform, transform);
-    }
-}
-
-fun task(name: String, builder: KTaskBuilder.() -> Unit): KTask<Any> {
-    return KTaskBuilder(name).apply(builder).build();
-}
\ No newline at end of file