Index: src/InitTweak/FixInit.cc
===================================================================
--- src/InitTweak/FixInit.cc	(revision b4bfa0ab5ab42396bb6826d98b8e96d3027512cd)
+++ src/InitTweak/FixInit.cc	(revision ac74057f200ca1db8599a011c8f8b2679a75beb0)
@@ -36,5 +36,4 @@
 #include "FixGlobalInit.h"             // for fixGlobalInit
 #include "GenInit.h"                   // for genCtorDtor
-#include "GenPoly/DeclMutator.h"       // for DeclMutator
 #include "GenPoly/GenPoly.h"           // for getFunctionType
 #include "GenPoly/PolyMutator.h"       // for PolyMutator
Index: src/InitTweak/GenInit.cc
===================================================================
--- src/InitTweak/GenInit.cc	(revision b4bfa0ab5ab42396bb6826d98b8e96d3027512cd)
+++ src/InitTweak/GenInit.cc	(revision ac74057f200ca1db8599a011c8f8b2679a75beb0)
@@ -26,5 +26,4 @@
 #include "Common/UniqueName.h"     // for UniqueName
 #include "Common/utility.h"        // for ValueGuard, maybeClone
-#include "GenPoly/DeclMutator.h"   // for DeclMutator
 #include "GenPoly/GenPoly.h"       // for getFunctionType, isPolyType
 #include "GenPoly/ScopedSet.h"     // for ScopedSet, ScopedSet<>::const_iter...
Index: src/SymTab/Autogen.cc
===================================================================
--- src/SymTab/Autogen.cc	(revision b4bfa0ab5ab42396bb6826d98b8e96d3027512cd)
+++ src/SymTab/Autogen.cc	(revision ac74057f200ca1db8599a011c8f8b2679a75beb0)
@@ -29,5 +29,4 @@
 #include "Common/ScopedMap.h"      // for ScopedMap<>::const_iterator, Scope...
 #include "Common/utility.h"        // for cloneAll, operator+
-#include "GenPoly/DeclMutator.h"   // for DeclMutator
 #include "GenPoly/ScopedSet.h"     // for ScopedSet, ScopedSet<>::iterator
 #include "InitTweak/GenInit.h"     // for fixReturnStatements
@@ -81,16 +80,10 @@
 
 	/// generates routines for tuple types.
-	/// Doesn't really need to be a mutator, but it's easier to reuse DeclMutator than it is to use AddVisit
-	/// or anything we currently have that supports adding new declarations for visitors
-	class AutogenTupleRoutines : public GenPoly::DeclMutator {
-	  public:
-		typedef GenPoly::DeclMutator Parent;
-		using Parent::mutate;
-
-		virtual DeclarationWithType * mutate( FunctionDecl *functionDecl );
-
-		virtual Type * mutate( TupleType *tupleType );
-
-		virtual CompoundStmt * mutate( CompoundStmt *compoundStmt );
+	struct AutogenTupleRoutines : public WithDeclsToAdd, public WithVisitorRef<AutogenTupleRoutines>, public WithGuards, public WithShortCircuiting {
+		void previsit( FunctionDecl *functionDecl );
+
+		void postvisit( TupleType *tupleType );
+
+		void previsit( CompoundStmt *compoundStmt );
 
 	  private:
@@ -105,5 +98,5 @@
 		// needs to be done separately because AutogenerateRoutines skips types that appear as function arguments, etc.
 		// AutogenTupleRoutines tupleGenerator;
-		// tupleGenerator.mutateDeclarationList( translationUnit );
+		// acceptAll( translationUnit, tupleGenerator );
 	}
 
@@ -707,8 +700,7 @@
 	}
 
-	Type * AutogenTupleRoutines::mutate( TupleType * tupleType ) {
-		tupleType = strict_dynamic_cast< TupleType * >( Parent::mutate( tupleType ) );
+	void AutogenTupleRoutines::postvisit( TupleType * tupleType ) {
 		std::string mangleName = SymTab::Mangler::mangleType( tupleType );
-		if ( seenTuples.find( mangleName ) != seenTuples.end() ) return tupleType;
+		if ( seenTuples.find( mangleName ) != seenTuples.end() ) return;
 		seenTuples.insert( mangleName );
 
@@ -758,25 +750,22 @@
 		makeTupleFunctionBody( dtorDecl );
 
-		addDeclaration( ctorDecl );
-		addDeclaration( copyCtorDecl );
-		addDeclaration( dtorDecl );
-		addDeclaration( assignDecl ); // assignment should come last since it uses copy constructor in return
-
-		return tupleType;
-	}
-
-	DeclarationWithType * AutogenTupleRoutines::mutate( FunctionDecl *functionDecl ) {
-		functionDecl->set_functionType( maybeMutate( functionDecl->get_functionType(), *this ) );
+		declsToAddBefore.push_back( ctorDecl );
+		declsToAddBefore.push_back( copyCtorDecl );
+		declsToAddBefore.push_back( dtorDecl );
+		declsToAddBefore.push_back( assignDecl ); // assignment should come last since it uses copy constructor in return
+
+		return;
+	}
+
+	void AutogenTupleRoutines::previsit( FunctionDecl *functionDecl ) {
+		visit_children = false;
+		functionDecl->set_functionType( maybeMutate( functionDecl->type, *visitor ) );
 		functionNesting += 1;
-		functionDecl->set_statements( maybeMutate( functionDecl->get_statements(), *this ) );
+		functionDecl->set_statements( maybeMutate( functionDecl->statements, *visitor ) );
 		functionNesting -= 1;
-		return functionDecl;
-	}
-
-	CompoundStmt * AutogenTupleRoutines::mutate( CompoundStmt *compoundStmt ) {
-		seenTuples.beginScope();
-		compoundStmt = strict_dynamic_cast< CompoundStmt * >( Parent::mutate( compoundStmt ) );
-		seenTuples.endScope();
-		return compoundStmt;
+	}
+
+	void AutogenTupleRoutines::previsit( CompoundStmt * ) {
+		GuardScope( seenTuples );
 	}
 } // SymTab
Index: src/Tuples/TupleExpansion.cc
===================================================================
--- src/Tuples/TupleExpansion.cc	(revision b4bfa0ab5ab42396bb6826d98b8e96d3027512cd)
+++ src/Tuples/TupleExpansion.cc	(revision ac74057f200ca1db8599a011c8f8b2679a75beb0)
@@ -21,5 +21,4 @@
 #include "Common/ScopedMap.h"     // for ScopedMap
 #include "Common/utility.h"       // for CodeLocation
-#include "GenPoly/DeclMutator.h"  // for DeclMutator
 #include "InitTweak/InitTweak.h"  // for getFunction
 #include "Parser/LinkageSpec.h"   // for Spec, C, Intrinsic