diff --git a/languages/jetbrains.mps.logic/sandbox/jetbrains.mps.logic.sandbox.msd b/languages/jetbrains.mps.logic/sandbox/jetbrains.mps.logic.sandbox.msd
index a3b280c6..b3fcab33 100644
--- a/languages/jetbrains.mps.logic/sandbox/jetbrains.mps.logic.sandbox.msd
+++ b/languages/jetbrains.mps.logic/sandbox/jetbrains.mps.logic.sandbox.msd
@@ -8,13 +8,21 @@
6354ebe7-c22a-4a0f-ac54-50b52ab9b065(JDK)
+ b984ee52-f34d-4b6d-8812-866c1d3eae31(jetbrains.mps.jchr.runtime)
+ 7ab0c079-df36-45eb-a614-81cf81174043(jetbrains.mps.jchr.sandbox)
a5478664-6b44-4c62-a9f7-434f8aa57eee(jetbrains.mps.logic.runtime)
+ 7526e0cf-1ce7-46f8-a555-9eca1e06c23b(jetbrains.mps.unification)
f3061a53-9226-4cc5-a443-f952ceaf5816(jetbrains.mps.baseLanguage)
fd392034-7849-419d-9071-12563d152375(jetbrains.mps.baseLanguage.closures)
+ df345b11-b8c7-4213-ac66-48d2a9b75d88(jetbrains.mps.baseLanguageInternal)
+ 894463aa-8754-49c0-bf4b-6a32af66b376(jetbrains.mps.jchr)
ceab5195-25ea-4f22-9b92-103b95ca8c0c(jetbrains.mps.lang.core)
35320f26-77cb-4c55-be9f-a97a27770af1(jetbrains.mps.logic)
+
+ fbc25dd2-5da4-483a-8b19-70928e1b62d7(jetbrains.mps.devkit.general-purpose)
+
diff --git a/languages/jetbrains.mps.logic/sandbox/models/jetbrains/mps/logic/sandbox.mps b/languages/jetbrains.mps.logic/sandbox/models/jetbrains/mps/logic/sandbox.mps
index e0ea08de..e07fab6e 100644
--- a/languages/jetbrains.mps.logic/sandbox/models/jetbrains/mps/logic/sandbox.mps
+++ b/languages/jetbrains.mps.logic/sandbox/models/jetbrains/mps/logic/sandbox.mps
@@ -553,12 +553,13 @@
-
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+
-
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diff --git a/languages/jetbrains.mps.logic/sandbox/models/jetbrains/mps/unification/sandbox.mps b/languages/jetbrains.mps.logic/sandbox/models/jetbrains/mps/unification/sandbox.mps
new file mode 100644
index 00000000..5bcb6ccb
--- /dev/null
+++ b/languages/jetbrains.mps.logic/sandbox/models/jetbrains/mps/unification/sandbox.mps
@@ -0,0 +1,253 @@
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diff --git a/languages/jetbrains.mps.logic/sandbox/models/jetbrains/mps/unification/util.mps b/languages/jetbrains.mps.logic/sandbox/models/jetbrains/mps/unification/util.mps
new file mode 100644
index 00000000..748c7427
--- /dev/null
+++ b/languages/jetbrains.mps.logic/sandbox/models/jetbrains/mps/unification/util.mps
@@ -0,0 +1,346 @@
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