diff --git a/reactor/Core/src/jetbrains/mps/logic/reactor/program/InvalidConstraintException.java b/reactor/Core/src/jetbrains/mps/logic/reactor/program/InvalidConstraintException.java
index 5ff93a16..5424868f 100644
--- a/reactor/Core/src/jetbrains/mps/logic/reactor/program/InvalidConstraintException.java
+++ b/reactor/Core/src/jetbrains/mps/logic/reactor/program/InvalidConstraintException.java
@@ -18,7 +18,7 @@ package jetbrains.mps.logic.reactor.program;
 
 
 
-public class InvalidConstraintException extends Exception {
+public class InvalidConstraintException extends RuntimeException {
 
     public InvalidConstraintException(String message) {
         super(message);