diff --git a/src/muz/spacer/spacer_legacy_mev.cpp b/src/muz/spacer/spacer_legacy_mev.cpp
index 69f479836..16e2cc734 100644
--- a/src/muz/spacer/spacer_legacy_mev.cpp
+++ b/src/muz/spacer/spacer_legacy_mev.cpp
@@ -5,11 +5,8 @@ Copyright (c) 2017 Arie Gurfinkel
 */
 
 #include <sstream>
-#include "ast/simplifier/arith_simplifier_plugin.h"
 #include "ast/array_decl_plugin.h"
 #include "ast/ast_pp.h"
-#include "ast/simplifier/basic_simplifier_plugin.h"
-#include "ast/simplifier/bv_simplifier_plugin.h"
 #include "ast/rewriter/bool_rewriter.h"
 #include "muz/base/dl_util.h"
 #include "ast/for_each_expr.h"
diff --git a/src/muz/spacer/spacer_legacy_mev.h b/src/muz/spacer/spacer_legacy_mev.h
index bebf1d0db..ff8f63d1f 100644
--- a/src/muz/spacer/spacer_legacy_mev.h
+++ b/src/muz/spacer/spacer_legacy_mev.h
@@ -10,7 +10,6 @@ Copyright (c) 2017 Arie Gurfinkel
 #include "ast/ast_pp.h"
 #include "util/obj_hashtable.h"
 #include "util/ref_vector.h"
-#include "ast/simplifier/simplifier.h"
 #include "util/trace.h"
 #include "util/vector.h"
 #include "ast/arith_decl_plugin.h"
diff --git a/src/muz/spacer/spacer_util.h b/src/muz/spacer/spacer_util.h
index 5bbb84bfb..546b7df5b 100644
--- a/src/muz/spacer/spacer_util.h
+++ b/src/muz/spacer/spacer_util.h
@@ -26,12 +26,13 @@ Revision History:
 #include "ast/ast_pp.h"
 #include "util/obj_hashtable.h"
 #include "util/ref_vector.h"
-#include "ast/simplifier/simplifier.h"
 #include "util/trace.h"
 #include "util/vector.h"
 #include "ast/arith_decl_plugin.h"
 #include "ast/array_decl_plugin.h"
 #include "ast/bv_decl_plugin.h"
+#include "ast/ast_util.h"
+#include "ast/expr_map.h"
 #include "model/model.h"
 
 #include "util/stopwatch.h"