diff --git a/lib/octofacts/backends/index.rb b/lib/octofacts/backends/index.rb
index 201df67..491591d 100644
--- a/lib/octofacts/backends/index.rb
+++ b/lib/octofacts/backends/index.rb
@@ -45,7 +45,7 @@ def select(conditions)
           add_fact_to_index(key) unless indexed_fact?(key)
           matching_nodes = index[key][value.to_s]
           raise Octofacts::Errors::NoFactsError if matching_nodes.nil?
-          self.nodes = nodes & matching_nodes
+          @nodes = nodes & matching_nodes
         end
 
         self