diff --git a/reactor/Core/src/jetbrains/mps/logic/reactor/core/internal/ControllerImpl.kt b/reactor/Core/src/jetbrains/mps/logic/reactor/core/internal/ControllerImpl.kt
index 12ce9819..f5951799 100644
--- a/reactor/Core/src/jetbrains/mps/logic/reactor/core/internal/ControllerImpl.kt
+++ b/reactor/Core/src/jetbrains/mps/logic/reactor/core/internal/ControllerImpl.kt
@@ -89,14 +89,14 @@ internal class ControllerImpl (
         processing
 
     override fun ask(invocation: PredicateInvocation): Boolean {
-        val solver = invocation.predicate().symbol().solver()
+        val solver = invocation.predicate().symbol().solver(supervisor)
         val result = solver.ask(invocation)
         trace.ask(result, invocation)
         return result
     }
 
     override fun tell(invocation: PredicateInvocation) {
-        val solver = invocation.predicate().symbol().solver()
+        val solver = invocation.predicate().symbol().solver(supervisor)
         trace.tell(invocation)
         solver.tell(invocation)
     }
diff --git a/reactor/Core/src/jetbrains/mps/logic/reactor/evaluation/DataProvider.java b/reactor/Core/src/jetbrains/mps/logic/reactor/evaluation/DataProvider.java
new file mode 100644
index 00000000..042958b3
--- /dev/null
+++ b/reactor/Core/src/jetbrains/mps/logic/reactor/evaluation/DataProvider.java
@@ -0,0 +1,58 @@
+/*
+ * Copyright 2014-2020 JetBrains s.r.o.
+ *
+ * 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 jetbrains.mps.logic.reactor.evaluation;
+
+import java.util.function.Supplier;
+
+/**
+ * @author Fedor Isakov
+ */
+public interface DataProvider {
+    
+    class Key<T> {
+
+        private final String name;
+
+        public Key(String name) {
+            this.name = name;
+        }
+
+        @Override
+        public int hashCode() {
+            return 17*name.hashCode();
+        }
+
+        @Override
+        public boolean equals(Object that) {
+            if (that == null) return false;
+            if (that.getClass() != Key.class) return false;
+            return this.name.equals(((Key) that).name);
+        }
+
+        @Override
+        public String toString() {
+            return name;
+        }
+    }
+
+    <T> T getData(Key<T> key);
+
+    <T> T getOrSetData(Key<T> key, Supplier<T> supplier);
+
+    <T> void setData(Key<T> key, T data);
+
+}
diff --git a/reactor/Core/src/jetbrains/mps/logic/reactor/program/PredicateSymbol.java b/reactor/Core/src/jetbrains/mps/logic/reactor/program/PredicateSymbol.java
index 26b24950..543a6a41 100644
--- a/reactor/Core/src/jetbrains/mps/logic/reactor/program/PredicateSymbol.java
+++ b/reactor/Core/src/jetbrains/mps/logic/reactor/program/PredicateSymbol.java
@@ -18,6 +18,7 @@ package jetbrains.mps.logic.reactor.program;
 
 
 import jetbrains.mps.logic.reactor.evaluation.Solver;
+import jetbrains.mps.logic.reactor.evaluation.Supervisor;
 
 /**
  * A predicate symbol.
@@ -32,6 +33,10 @@ public abstract class PredicateSymbol extends Symbol {
 
     public abstract Solver solver();
 
+    public Solver solver(Supervisor supervisor) {
+        return solver();
+    }
+
     @Override
     public String toString() {
         return id() + "()/" + arity();