diff --git a/lib/baes/actions/bisect.rb b/lib/baes/actions/bisect.rb
index 3798609..386402a 100644
--- a/lib/baes/actions/bisect.rb
+++ b/lib/baes/actions/bisect.rb
@@ -51,10 +51,7 @@ def find_middle_branch(success_branch, fail_branch)
       start_number = success_branch.number
 
       child_branch =
-        success_branch.children.find do |next_child_branch|
-          next_child_branch.base_name == fail_branch.base_name
-        end
-
+        success_branch.children.find_by_base_name(fail_branch.base_name)
       start_number ||= child_branch.number
 
       middle_number = (start_number + end_number) / 2
@@ -63,9 +60,7 @@ def find_middle_branch(success_branch, fail_branch)
 
       while next_branch.number < middle_number
         next_branch =
-          next_branch.children.find do |next_child_branch|
-            next_child_branch.base_name == fail_branch.base_name
-          end
+          next_branch.children.find_by_base_name(fail_branch.base_name)
       end
 
       next_branch
diff --git a/lib/baes/branch.rb b/lib/baes/branch.rb
index cf89122..ef1b7f3 100644
--- a/lib/baes/branch.rb
+++ b/lib/baes/branch.rb
@@ -12,7 +12,7 @@ def initialize(name)
     _, base_name, number = name.match(/(\A[a-zA-Z_-]+)(\d+)$/).to_a
     self.base_name = base_name || name
     self.number = number && Integer(number, 10)
-    self.children = []
+    self.children = Baes::BranchCollection.new
   end
 
   # return an array for use as a hash key
diff --git a/lib/baes/branch_collection.rb b/lib/baes/branch_collection.rb
index 1dffc6c..c510758 100644
--- a/lib/baes/branch_collection.rb
+++ b/lib/baes/branch_collection.rb
@@ -24,11 +24,21 @@ def find_by_name(name)
     branches.find { |branch| branch.name == name }
   end
 
+  # find a branch by base name
+  def find_by_base_name(base_name)
+    branches.find { |branch| branch.base_name == base_name }
+  end
+
   # add a branch
   def <<(branch)
     branches << branch
   end
 
+  # delete a branch if the block returns true
+  def delete_if(&block)
+    branches.delete_if(&block)
+  end
+
   # iterate over each branch with object
   def each_with_object(obj, &block)
     branches.each_with_object(obj, &block)
@@ -39,6 +49,16 @@ def each(&block)
     branches.each(&block)
   end
 
+  # return true if there are no branches
+  def empty?
+    branches.empty?
+  end
+
+  # iterate over each branch and return the result
+  def map(&block)
+    branches.map(&block)
+  end
+
   # return the first branch
   def first
     branches.first