diff --git a/samples/mpscore/build.xml b/samples/mpscore/build.xml
index 65a665d9..0974cf96 100644
--- a/samples/mpscore/build.xml
+++ b/samples/mpscore/build.xml
@@ -3110,6 +3110,7 @@
           <module ref="a5478664-6b44-4c62-a9f7-434f8aa57eee(jetbrains.mps.logic.runtime)" kind="rt" />
           <module ref="8fe4c62a-2020-4ff4-8eda-f322a55bdc9f(jetbrains.mps.refactoring.runtime)" kind="rt" />
           <module ref="9a4afe51-f114-4595-b5df-048ce3c596be(jetbrains.mps.runtime)" kind="rt" />
+          <module ref="9b80526e-f0bf-4992-bdf5-cee39c1833f3(collections.runtime)" kind="cl" />
           <module ref="9e36d2ee-c59c-4580-9e81-646748d0614b(jetbrains.mps.baseLanguage.closuresExt)" kind="cl" />
           <module ref="83888646-71ce-4f1c-9c53-c54016f6ad4f(jetbrains.mps.baseLanguage.collections)" kind="cl" />
           <module ref="96eeb076-cd7e-4797-9c2a-348e3f826e65(jetbrains.mps.baseLanguage.function)" kind="cl" />
@@ -8580,6 +8581,7 @@
           <module ref="a5478664-6b44-4c62-a9f7-434f8aa57eee(jetbrains.mps.logic.runtime)" kind="rt" />
           <module ref="8fe4c62a-2020-4ff4-8eda-f322a55bdc9f(jetbrains.mps.refactoring.runtime)" kind="rt" />
           <module ref="9a4afe51-f114-4595-b5df-048ce3c596be(jetbrains.mps.runtime)" kind="rt" />
+          <module ref="9b80526e-f0bf-4992-bdf5-cee39c1833f3(collections.runtime)" kind="cl" />
           <module ref="9e36d2ee-c59c-4580-9e81-646748d0614b(jetbrains.mps.baseLanguage.closuresExt)" kind="cl" />
           <module ref="83888646-71ce-4f1c-9c53-c54016f6ad4f(jetbrains.mps.baseLanguage.collections)" kind="cl" />
           <module ref="96eeb076-cd7e-4797-9c2a-348e3f826e65(jetbrains.mps.baseLanguage.function)" kind="cl" />
diff --git a/samples/mpscore/languages/jetbrains.mps.baseLanguage.collectionsExt/jetbrains.mps.baseLanguage.collectionsExt.mpl b/samples/mpscore/languages/jetbrains.mps.baseLanguage.collectionsExt/jetbrains.mps.baseLanguage.collectionsExt.mpl
index 6d5a27c8..37acfb2f 100644
--- a/samples/mpscore/languages/jetbrains.mps.baseLanguage.collectionsExt/jetbrains.mps.baseLanguage.collectionsExt.mpl
+++ b/samples/mpscore/languages/jetbrains.mps.baseLanguage.collectionsExt/jetbrains.mps.baseLanguage.collectionsExt.mpl
@@ -66,6 +66,9 @@
       <mapping-priorities />
     </generator>
   </generators>
+  <dependencies>
+    <dependency reexport="false">9b80526e-f0bf-4992-bdf5-cee39c1833f3(collections.runtime)</dependency>
+  </dependencies>
   <languageVersions>
     <language slang="l:f3061a53-9226-4cc5-a443-f952ceaf5816:jetbrains.mps.baseLanguage" version="12" />
     <language slang="l:443f4c36-fcf5-4eb6-9500-8d06ed259e3e:jetbrains.mps.baseLanguage.classifiers" version="0" />
@@ -121,6 +124,7 @@
     <module reference="6354ebe7-c22a-4a0f-ac54-50b52ab9b065(JDK)" version="0" />
     <module reference="6ed54515-acc8-4d1e-a16c-9fd6cfe951ea(MPS.Core)" version="0" />
     <module reference="8865b7a8-5271-43d3-884c-6fd1d9cfdd34(MPS.OpenAPI)" version="0" />
+    <module reference="9b80526e-f0bf-4992-bdf5-cee39c1833f3(collections.runtime)" version="0" />
     <module reference="f3061a53-9226-4cc5-a443-f952ceaf5816(jetbrains.mps.baseLanguage)" version="0" />
     <module reference="fd392034-7849-419d-9071-12563d152375(jetbrains.mps.baseLanguage.closures)" version="0" />
     <module reference="9e36d2ee-c59c-4580-9e81-646748d0614b(jetbrains.mps.baseLanguage.closuresExt)" version="0" />
diff --git a/samples/mpscore/languages/jetbrains.mps.baseLanguage.collectionsExt/models/jetbrains.mps.baseLanguage.collectionsExt.types.mps b/samples/mpscore/languages/jetbrains.mps.baseLanguage.collectionsExt/models/jetbrains.mps.baseLanguage.collectionsExt.types.mps
index bd3aa51a..48e0ade5 100644
--- a/samples/mpscore/languages/jetbrains.mps.baseLanguage.collectionsExt/models/jetbrains.mps.baseLanguage.collectionsExt.types.mps
+++ b/samples/mpscore/languages/jetbrains.mps.baseLanguage.collectionsExt/models/jetbrains.mps.baseLanguage.collectionsExt.types.mps
@@ -15,6 +15,7 @@
     <import index="fa4b" ref="r:57e7708d-cfea-4f42-80e2-39fcd20eebc8(jetbrains.mps.baseLanguage.function.types)" />
     <import index="82uw" ref="6354ebe7-c22a-4a0f-ac54-50b52ab9b065/java:java.util.function(JDK/)" />
     <import index="e9ez" ref="r:ffe541d0-0912-42c1-800b-d2f22dd8a4c8(jetbrains.mps.baseLanguage.closuresExt.types)" />
+    <import index="urs3" ref="r:fc76aa36-3cff-41c7-b94b-eee0e8341932(jetbrains.mps.internal.collections.runtime)" />
     <import index="tp2z" ref="r:00000000-0000-4000-0000-011c89590327(jetbrains.mps.baseLanguage.collections.behavior)" implicit="true" />
     <import index="tpee" ref="r:00000000-0000-4000-0000-011c895902ca(jetbrains.mps.baseLanguage.structure)" implicit="true" />
     <import index="tpek" ref="r:00000000-0000-4000-0000-011c895902c0(jetbrains.mps.baseLanguage.behavior)" implicit="true" />
@@ -3272,6 +3273,350 @@
         </node>
       </node>
     </node>
+    <node concept="1nLNMY" id="2r1jTXMATP5" role="1nK1Vg">
+      <property role="TrG5h" value="converts_enumerator_runtimeType" />
+      <node concept="3clFbS" id="2r1jTXMATP6" role="1nLNMH">
+        <node concept="1nLNNL" id="2r1jTXMATP7" role="3cqZAp">
+          <node concept="1nLNMm" id="2r1jTXMATP8" role="1nLNNK">
+            <node concept="3xSepi" id="2r1jTXMATP9" role="3xSepv">
+              <node concept="3Aq9E8" id="2r1jTXMATPa" role="3xSepj">
+                <node concept="3I6sU6" id="2r1jTXMATPb" role="3Ip0Jz">
+                  <node concept="3I6s7M" id="2r1jTXMATPc" role="3I6sU7">
+                    <node concept="3Aqt3T" id="2r1jTXMATPd" role="3I6s78">
+                      <ref role="3AqCNq" node="1oUE7CX4KkY" resolve="toRuntimeType" />
+                      <node concept="a7P8L" id="2r1jTXMATPe" role="3AunhB">
+                        <ref role="a7OzE" node="2r1jTXMATPz" resolve="RuntimeType" />
+                      </node>
+                      <node concept="a7P8L" id="2r1jTXMATPf" role="3AunhB">
+                        <ref role="a7OzE" node="2r1jTXMATPx" resolve="It" />
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+                      <ref role="3AqCNq" to="kqnc:3vTJNooZDgN" resolve="convertsTo" />
+                      <node concept="a7P8L" id="2r1jTXMATPi" role="3AunhB">
+                        <ref role="a7OzE" node="2r1jTXMATPy" resolve="Cls" />
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+                      <node concept="a7P8L" id="2r1jTXMATPj" role="3AunhB">
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+                      <node concept="a7P8L" id="2r1jTXMATPk" role="3AunhB">
+                        <ref role="a7OzE" node="2r1jTXMATPB" resolve="Options" />
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+            <node concept="3Aq93q" id="2r1jTXMATPl" role="1nLNMb">
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+                      <node concept="ns1u0" id="2r1jTXMATPr" role="1uarlW">
+                        <ref role="ns1xF" to="kqnc:JOGAOsVt2a" resolve="classifier" />
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+                      <node concept="ns1u0" id="2r1jTXMAUha" role="1uarlW">
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+              <node concept="aZer4" id="2r1jTXMATPx" role="3XD1gS">
+                <property role="TrG5h" value="It" />
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+              <node concept="aZer4" id="2r1jTXMATPy" role="3XD1gS">
+                <property role="TrG5h" value="Cls" />
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+              <node concept="aZer4" id="2r1jTXMATPz" role="3XD1gS">
+                <property role="TrG5h" value="RuntimeType" />
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+            <node concept="3NuqgR" id="2r1jTXMATP_" role="0Rg$4">
+              <node concept="3uibUv" id="2r1jTXMATPA" role="3vLBG7">
+                <ref role="3uigEE" to="kqnc:3vTJNooZBhQ" resolve="ConvertsContext.Options" />
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+              <node concept="aZer4" id="2r1jTXMATPB" role="3XD1gS">
+                <property role="TrG5h" value="Options" />
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+          </node>
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+        <node concept="3clFbH" id="2r1jTXMATPC" role="3cqZAp" />
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+                  <node concept="3Aqt3T" id="2r1jTXMATPU" role="3I6s78">
+                    <ref role="3AqCNq" to="kqnc:3vTJNooZDgN" resolve="convertsTo" />
+                    <node concept="1HFMs5" id="2r1jTXMATPV" role="3AunhB">
+                      <node concept="a7P8L" id="2r1jTXMATPW" role="1uarlU">
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+                      </node>
+                      <node concept="ns1u0" id="2r1jTXMAUiM" role="1uarlW">
+                        <ref role="ns1xF" node="1oUE7CX3txV" resolve="enumerator" />
+                      </node>
+                    </node>
+                    <node concept="1HFMs5" id="2r1jTXMATPY" role="3AunhB">
+                      <node concept="a7P8L" id="2r1jTXMATPZ" role="1uarlU">
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+                      <node concept="ns1u0" id="2r1jTXMATQ0" role="1uarlW">
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+              <node concept="aZer4" id="2r1jTXMATQ3" role="3XD1gS">
+                <property role="TrG5h" value="It" />
+              </node>
+              <node concept="aZer4" id="2r1jTXMATQ4" role="3XD1gS">
+                <property role="TrG5h" value="Cls" />
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+                <property role="TrG5h" value="RuntimeType" />
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+                <property role="TrG5h" value="Options" />
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+            </node>
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+                    </node>
+                  </node>
+                  <node concept="3I6s7M" id="2r1jTXMAXsA" role="3I6sU7">
+                    <node concept="3Aqt3T" id="2r1jTXMAXsB" role="3I6s78">
+                      <ref role="3AqCNq" to="kqnc:3vTJNooZDgN" resolve="convertsTo" />
+                      <node concept="a7P8L" id="2r1jTXMAXsC" role="3AunhB">
+                        <ref role="a7OzE" node="2r1jTXMAXsT" resolve="RuntimeType" />
+                      </node>
+                      <node concept="a7P8L" id="2r1jTXMAXsD" role="3AunhB">
+                        <ref role="a7OzE" node="2r1jTXMAXsS" resolve="Cls" />
+                      </node>
+                      <node concept="a7P8L" id="2r1jTXMAXsE" role="3AunhB">
+                        <ref role="a7OzE" node="2r1jTXMAXsX" resolve="Options" />
+                      </node>
+                    </node>
+                  </node>
+                </node>
+              </node>
+            </node>
+            <node concept="3Aq93q" id="2r1jTXMAXsF" role="1nLNMb">
+              <node concept="3I6sU6" id="2r1jTXMAXsG" role="3Ip0Jz">
+                <node concept="3I6s7M" id="2r1jTXMAXsH" role="3I6sU7">
+                  <node concept="3Aqt3T" id="2r1jTXMAXsI" role="3I6s78">
+                    <ref role="3AqCNq" to="kqnc:3vTJNooZDgN" resolve="convertsTo" />
+                    <node concept="1HFMs5" id="2r1jTXMAXsJ" role="3AunhB">
+                      <node concept="a7P8L" id="2r1jTXMAXsK" role="1uarlU">
+                        <ref role="a7OzE" node="2r1jTXMAXsR" resolve="It" />
+                      </node>
+                      <node concept="ns1u0" id="2r1jTXMAY8P" role="1uarlW">
+                        <ref role="ns1xF" node="1oUE7CX3tye" resolve="mapping" />
+                      </node>
+                    </node>
+                    <node concept="1HFMs5" id="2r1jTXMAXsM" role="3AunhB">
+                      <node concept="a7P8L" id="2r1jTXMAXsN" role="1uarlU">
+                        <ref role="a7OzE" node="2r1jTXMAXsS" resolve="Cls" />
+                      </node>
+                      <node concept="ns1u0" id="2r1jTXMAXsO" role="1uarlW">
+                        <ref role="ns1xF" to="kqnc:JOGAOsVt2a" resolve="classifier" />
+                      </node>
+                    </node>
+                    <node concept="a7P8L" id="2r1jTXMAXsP" role="3AunhB">
+                      <ref role="a7OzE" node="2r1jTXMAXsX" resolve="Options" />
+                    </node>
+                  </node>
+                </node>
+              </node>
+            </node>
+            <node concept="3NuqgR" id="2r1jTXMAXsQ" role="0Rg$4">
+              <node concept="aZer4" id="2r1jTXMAXsR" role="3XD1gS">
+                <property role="TrG5h" value="It" />
+              </node>
+              <node concept="aZer4" id="2r1jTXMAXsS" role="3XD1gS">
+                <property role="TrG5h" value="Cls" />
+              </node>
+              <node concept="aZer4" id="2r1jTXMAXsT" role="3XD1gS">
+                <property role="TrG5h" value="RuntimeType" />
+              </node>
+              <node concept="32pEOW" id="2r1jTXMAXsU" role="3vLBG7" />
+            </node>
+            <node concept="3NuqgR" id="2r1jTXMAXsV" role="0Rg$4">
+              <node concept="3uibUv" id="2r1jTXMAXsW" role="3vLBG7">
+                <ref role="3uigEE" to="kqnc:3vTJNooZBhQ" resolve="ConvertsContext.Options" />
+              </node>
+              <node concept="aZer4" id="2r1jTXMAXsX" role="3XD1gS">
+                <property role="TrG5h" value="Options" />
+              </node>
+            </node>
+          </node>
+        </node>
+      </node>
+    </node>
     <node concept="1nLNMY" id="1oUE7CX62pI" role="1nK1Vg">
       <property role="TrG5h" value="converts_collections_intro" />
       <node concept="3clFbS" id="1oUE7CX62pJ" role="1nLNMH">
@@ -3411,7 +3756,7 @@
       </node>
     </node>
     <node concept="1nLNMY" id="1oUE7CX62$N" role="1nK1Vg">
-      <property role="TrG5h" value="converts_enumerator_id" />
+      <property role="TrG5h" value="converts_enumerator_covariant" />
       <node concept="3clFbS" id="1oUE7CX62$O" role="1nLNMH">
         <node concept="1nLNNL" id="1oUE7CX62$P" role="3cqZAp">
           <node concept="1nLNMm" id="1oUE7CX62$Q" role="1nLNNK">
@@ -5024,6 +5369,198 @@
         </node>
       </node>
     </node>
+    <node concept="1nLNMY" id="2r1jTXMzTE4" role="1nK1Vg">
+      <property role="TrG5h" value="enumerator_toRuntimeType" />
+      <node concept="3clFbS" id="2r1jTXMzTE5" role="1nLNMH">
+        <node concept="1mebxG" id="2r1jTXMzTE6" role="3cqZAp">
+          <node concept="2tJFMh" id="2r1jTXMzTE7" role="1mebXD">
+            <node concept="ZC_QK" id="2r1jTXMzTE8" role="2tJFKM">
+              <ref role="2aWVGs" to="urs3:5Ffu4tBUxgb" resolve="IEnumerator" />
+            </node>
+          </node>
+        </node>
+        <node concept="3clFbH" id="2r1jTXMzTE9" role="3cqZAp" />
+        <node concept="1nLNNL" id="2r1jTXMzTEa" role="3cqZAp">
+          <node concept="1nLNMm" id="2r1jTXMzTEb" role="1nLNNK">
+            <node concept="3Aq93q" id="2r1jTXMzTEc" role="1nLNMb">
+              <node concept="3I6sU6" id="2r1jTXMzTEd" role="3Ip0Jz">
+                <node concept="3I6s7M" id="2r1jTXMzTEe" role="3I6sU7">
+                  <node concept="3Aqt3T" id="2r1jTXMzTEf" role="3I6s78">
+                    <ref role="3AqCNq" node="1oUE7CX4KkY" resolve="toRuntimeType" />
+                    <node concept="a7P8L" id="2r1jTXMzTEg" role="3AunhB">
+                      <ref role="a7OzE" node="2r1jTXMzTEn" resolve="RuntimeType" />
+                    </node>
+                    <node concept="1HFMs5" id="2r1jTXMzTEh" role="3AunhB">
+                      <node concept="a7P8L" id="2r1jTXMzTEi" role="1uarlU">
+                        <ref role="a7OzE" node="2r1jTXMzTEo" resolve="It" />
+                      </node>
+                      <node concept="ns1u0" id="2r1jTXMzTEj" role="1uarlW">
+                        <ref role="ns1xF" node="1oUE7CX3txV" resolve="enumerator" />
+                        <node concept="nsMwS" id="2r1jTXMzTEk" role="ns1xD">
+                          <ref role="nsMwP" node="1oUE7CX3tyc" resolve="elem" />
+                          <node concept="a7P8L" id="2r1jTXMzTEl" role="iSaTp">
+                            <ref role="a7OzE" node="2r1jTXMzTEp" resolve="Elem" />
+                          </node>
+                        </node>
+                      </node>
+                    </node>
+                  </node>
+                </node>
+              </node>
+            </node>
+            <node concept="3NuqgR" id="2r1jTXMzTEm" role="0Rg$4">
+              <node concept="aZer4" id="2r1jTXMzTEn" role="3XD1gS">
+                <property role="TrG5h" value="RuntimeType" />
+              </node>
+              <node concept="aZer4" id="2r1jTXMzTEo" role="3XD1gS">
+                <property role="TrG5h" value="It" />
+              </node>
+              <node concept="aZer4" id="2r1jTXMzTEp" role="3XD1gS">
+                <property role="TrG5h" value="Elem" />
+              </node>
+              <node concept="32pEOW" id="2r1jTXMzTEq" role="3vLBG7" />
+            </node>
+            <node concept="3xSepi" id="2r1jTXMzTEr" role="3xSepv">
+              <node concept="3Aq9E8" id="2r1jTXMzTEs" role="3xSepj">
+                <node concept="3I6sU6" id="2r1jTXMzTEt" role="3Ip0Jz">
+                  <node concept="3I6s7M" id="2r1jTXMzTEu" role="3I6sU7">
+                    <node concept="3A8Hvi" id="2r1jTXMzTEv" role="3I6s78">
+                      <node concept="ns1u0" id="2r1jTXMzTEw" role="3A8w4Q">
+                        <ref role="ns1xF" to="kqnc:JOGAOsVt2a" resolve="classifier" />
+                        <node concept="nsMwS" id="2r1jTXMzTEx" role="ns1xD">
+                          <ref role="nsMwP" to="kqnc:JOGAOsVt2c" resolve="classifier" />
+                          <node concept="h$QuP" id="2r1jTXMzTEy" role="iSaTp">
+                            <ref role="h$OrH" to="urs3:5Ffu4tBUxgb" resolve="IEnumerator" />
+                          </node>
+                        </node>
+                        <node concept="nsMwS" id="2r1jTXMzTEz" role="ns1xD">
+                          <ref role="nsMwP" to="kqnc:ZJPHcupkiC" resolve="typeParams" />
+                          <node concept="Hz6ka" id="2r1jTXMzTE$" role="iSaTp">
+                            <node concept="KCUsM" id="2r1jTXMzTE_" role="Hz6kd">
+                              <node concept="3wAshV" id="2r1jTXMzTEA" role="KCVpo">
+                                <node concept="a7P8L" id="2r1jTXMzTEB" role="3wAq21">
+                                  <ref role="a7OzE" node="2r1jTXMzTEp" resolve="Elem" />
+                                </node>
+                              </node>
+                            </node>
+                          </node>
+                        </node>
+                      </node>
+                      <node concept="a7P8L" id="2r1jTXMzTEC" role="3A8wtg">
+                        <ref role="a7OzE" node="2r1jTXMzTEn" resolve="RuntimeType" />
+                      </node>
+                    </node>
+                  </node>
+                </node>
+              </node>
+            </node>
+          </node>
+        </node>
+      </node>
+    </node>
+    <node concept="1nLNMY" id="2r1jTXMAXH6" role="1nK1Vg">
+      <property role="TrG5h" value="mapping_toRuntimeType" />
+      <node concept="3clFbS" id="2r1jTXMAXH7" role="1nLNMH">
+        <node concept="1mebxG" id="2r1jTXMAXH8" role="3cqZAp">
+          <node concept="2tJFMh" id="2r1jTXMAXH9" role="1mebXD">
+            <node concept="ZC_QK" id="2r1jTXMAXHa" role="2tJFKM">
+              <ref role="2aWVGs" to="urs3:5Ffu4tBUyxI" resolve="IMapping" />
+            </node>
+          </node>
+        </node>
+        <node concept="3clFbH" id="2r1jTXMAXHb" role="3cqZAp" />
+        <node concept="1nLNNL" id="2r1jTXMAXHc" role="3cqZAp">
+          <node concept="1nLNMm" id="2r1jTXMAXHd" role="1nLNNK">
+            <node concept="3Aq93q" id="2r1jTXMAXHe" role="1nLNMb">
+              <node concept="3I6sU6" id="2r1jTXMAXHf" role="3Ip0Jz">
+                <node concept="3I6s7M" id="2r1jTXMAXHg" role="3I6sU7">
+                  <node concept="3Aqt3T" id="2r1jTXMAXHh" role="3I6s78">
+                    <ref role="3AqCNq" node="1oUE7CX4KkY" resolve="toRuntimeType" />
+                    <node concept="a7P8L" id="2r1jTXMAXHi" role="3AunhB">
+                      <ref role="a7OzE" node="2r1jTXMAXHp" resolve="RuntimeType" />
+                    </node>
+                    <node concept="1HFMs5" id="2r1jTXMAXHj" role="3AunhB">
+                      <node concept="a7P8L" id="2r1jTXMAXHk" role="1uarlU">
+                        <ref role="a7OzE" node="2r1jTXMAXHq" resolve="It" />
+                      </node>
+                      <node concept="ns1u0" id="2r1jTXMAXHl" role="1uarlW">
+                        <ref role="ns1xF" node="1oUE7CX3tye" resolve="mapping" />
+                        <node concept="nsMwS" id="2r1jTXMAXHm" role="ns1xD">
+                          <ref role="nsMwP" node="1oUE7CX3tyy" resolve="key" />
+                          <node concept="a7P8L" id="2r1jTXMAXHn" role="iSaTp">
+                            <ref role="a7OzE" node="2r1jTXMAXHr" resolve="Elem" />
+                          </node>
+                        </node>
+                        <node concept="nsMwS" id="2r1jTXMAXVP" role="ns1xD">
+                          <ref role="nsMwP" node="1oUE7CX3tyB" resolve="value" />
+                          <node concept="a7P8L" id="2r1jTXMAY3L" role="iSaTp">
+                            <ref role="a7OzE" node="2r1jTXMAY2D" resolve="V" />
+                          </node>
+                        </node>
+                      </node>
+                    </node>
+                  </node>
+                </node>
+              </node>
+            </node>
+            <node concept="3NuqgR" id="2r1jTXMAXHo" role="0Rg$4">
+              <node concept="aZer4" id="2r1jTXMAXHp" role="3XD1gS">
+                <property role="TrG5h" value="RuntimeType" />
+              </node>
+              <node concept="aZer4" id="2r1jTXMAXHq" role="3XD1gS">
+                <property role="TrG5h" value="It" />
+              </node>
+              <node concept="aZer4" id="2r1jTXMAXHr" role="3XD1gS">
+                <property role="TrG5h" value="K" />
+              </node>
+              <node concept="aZer4" id="2r1jTXMAY2D" role="3XD1gS">
+                <property role="TrG5h" value="V" />
+              </node>
+              <node concept="32pEOW" id="2r1jTXMAXHs" role="3vLBG7" />
+            </node>
+            <node concept="3xSepi" id="2r1jTXMAXHt" role="3xSepv">
+              <node concept="3Aq9E8" id="2r1jTXMAXHu" role="3xSepj">
+                <node concept="3I6sU6" id="2r1jTXMAXHv" role="3Ip0Jz">
+                  <node concept="3I6s7M" id="2r1jTXMAXHw" role="3I6sU7">
+                    <node concept="3A8Hvi" id="2r1jTXMAXHx" role="3I6s78">
+                      <node concept="ns1u0" id="2r1jTXMAXHy" role="3A8w4Q">
+                        <ref role="ns1xF" to="kqnc:JOGAOsVt2a" resolve="classifier" />
+                        <node concept="nsMwS" id="2r1jTXMAXHz" role="ns1xD">
+                          <ref role="nsMwP" to="kqnc:JOGAOsVt2c" resolve="classifier" />
+                          <node concept="h$QuP" id="2r1jTXMAXH$" role="iSaTp">
+                            <ref role="h$OrH" to="urs3:5Ffu4tBUyxI" resolve="IMapping" />
+                          </node>
+                        </node>
+                        <node concept="nsMwS" id="2r1jTXMAXH_" role="ns1xD">
+                          <ref role="nsMwP" to="kqnc:ZJPHcupkiC" resolve="typeParams" />
+                          <node concept="Hz6ka" id="2r1jTXMAXHA" role="iSaTp">
+                            <node concept="KCUsM" id="2r1jTXMAXHB" role="Hz6kd">
+                              <node concept="3wAshV" id="2r1jTXMAXHC" role="KCVpo">
+                                <node concept="a7P8L" id="2r1jTXMAXHD" role="3wAq21">
+                                  <ref role="a7OzE" node="2r1jTXMAXHr" resolve="Elem" />
+                                </node>
+                              </node>
+                              <node concept="3wAshV" id="2r1jTXMAY3X" role="KCVpo">
+                                <node concept="a7P8L" id="2r1jTXMAY3W" role="3wAq21">
+                                  <ref role="a7OzE" node="2r1jTXMAY2D" resolve="V" />
+                                </node>
+                              </node>
+                            </node>
+                          </node>
+                        </node>
+                      </node>
+                      <node concept="a7P8L" id="2r1jTXMAXHE" role="3A8wtg">
+                        <ref role="a7OzE" node="2r1jTXMAXHp" resolve="RuntimeType" />
+                      </node>
+                    </node>
+                  </node>
+                </node>
+              </node>
+            </node>
+          </node>
+        </node>
+      </node>
+    </node>
     <node concept="1nLNMY" id="1oUE7CX62D0" role="1nK1Vg">
       <property role="TrG5h" value="toRuntimeType_fail" />
       <node concept="3clFbS" id="1oUE7CX62D1" role="1nLNMH">
diff --git a/samples/mpscore/solutions/jetbrains.mps.baseLanguage.collectionsExt.test/models/jetbrains.mps.baseLanguage.collectionsExt.test.collections.mps b/samples/mpscore/solutions/jetbrains.mps.baseLanguage.collectionsExt.test/models/jetbrains.mps.baseLanguage.collectionsExt.test.collections.mps
index adeb0f69..d4c4e3ed 100644
--- a/samples/mpscore/solutions/jetbrains.mps.baseLanguage.collectionsExt.test/models/jetbrains.mps.baseLanguage.collectionsExt.test.collections.mps
+++ b/samples/mpscore/solutions/jetbrains.mps.baseLanguage.collectionsExt.test/models/jetbrains.mps.baseLanguage.collectionsExt.test.collections.mps
@@ -3754,6 +3754,9 @@
             <node concept="37vLTw" id="3Z1xyIwB8eJ" role="37vLTJ">
               <ref role="3cqZAo" node="3Z1xyIwAZ4L" resolve="jitB" />
             </node>
+            <node concept="1U20sH" id="2r1jTXMEcf6" role="lGtFl">
+              <property role="1U20sK" value="error" />
+            </node>
           </node>
         </node>
         <node concept="3clFbH" id="3Z1xyIwB5gM" role="3cqZAp" />
diff --git a/samples/mpscore/solutions/samples.mpscore.build/models/samples.mpscore.build.mps b/samples/mpscore/solutions/samples.mpscore.build/models/samples.mpscore.build.mps
index 6c65bdfb..b2d4bb3b 100644
--- a/samples/mpscore/solutions/samples.mpscore.build/models/samples.mpscore.build.mps
+++ b/samples/mpscore/solutions/samples.mpscore.build/models/samples.mpscore.build.mps
@@ -2441,6 +2441,11 @@
             <ref role="1Busuk" node="6$MmqWflyOZ" resolve="jetbrains.mps.baseLanguage.closuresExt" />
           </node>
         </node>
+        <node concept="1SiIV0" id="2r1jTXMF04z" role="3bR37C">
+          <node concept="3bR9La" id="2r1jTXMF04$" role="1SiIV1">
+            <ref role="3bR37D" to="ffeo:7Kfy9QB6L0C" resolve="collections.runtime" />
+          </node>
+        </node>
       </node>
       <node concept="1E1JtD" id="6BFOg89KVoY" role="2G$12L">
         <property role="BnDLt" value="true" />