diff --git a/classes/nvd_downloader.rb b/classes/nvd_downloader.rb
index 9d465d9..dec2699 100644
--- a/classes/nvd_downloader.rb
+++ b/classes/nvd_downloader.rb
@@ -3,14 +3,16 @@ require 'zlib'
 require 'json'
 
 class NvdDownloader
-    attr_accessor :base_url, :years
+    attr_accessor :version, :base_url, :base_filename, :years
 
     MIN_YEAR = '2002'
     MAX_YEAR = '2019'
     AVAILABLE_YEARS = (MIN_YEAR..MAX_YEAR).to_a
 
     def initialize
-        @base_url = "https://nvd.nist.gov/feeds/json/cve/1.0/"
+        @version = "1.0"
+        @base_url = "https://nvd.nist.gov/feeds/json/cve/#{version}/"
+        @base_filename = "nvdcve-#{version}-"
         @years = self.years
     end
 
@@ -20,8 +22,17 @@ class NvdDownloader
         end.to_h
     end
 
-    def year(year)
-        years[year]
+    def filenames(extension)
+        year_filenames = years.map do |k, year|
+            "#{base_filename}#{year}.#{extension}"
+        end
+
+        other_filenames = [ 
+            "#{base_filename}recent.#{extension}",
+            "#{base_filename}modified.#{extension}"
+        ]
+
+        year_filenames + other_filenames
     end
 
     def get(url)
@@ -35,7 +46,21 @@ class NvdDownloader
         gz.read
     end
 
+    def write_to_file(parsed_json, file_path)
+        File.write(file_path, parsed_json)
+    end
+
     def parse_json(json_string)
         JSON.parse(json_string)
     end
+
+    def one_time_import
+        # this should be a method that does a one-time import
+        # of all of the json.gz from each year + recent + modified json feeds
+    end
+
+    def modified_meta
+        # this should be a method that builds 
+        # the modified filename with the meta file extension included
+    end
 end
\ No newline at end of file