diff --git a/src/branch_tier.hpp b/src/branch_tier.hpp
index a660044f..8279b5ab 100644
--- a/src/branch_tier.hpp
+++ b/src/branch_tier.hpp
@@ -15,6 +15,10 @@ public:
 public:
   uint64_t min_free_space;
 
+public:
+  std::vector<Branch2>::iterator begin() { return _branches.begin(); }
+  std::vector<Branch2>::iterator end() { return _branches.end(); }
+
 private:
   std::vector<Branch2>  _branches;
 };