diff --git a/plugins/commands/serve/mappers/known_types.rb b/plugins/commands/serve/mappers/known_types.rb
index adf18909a..0f4de83e1 100644
--- a/plugins/commands/serve/mappers/known_types.rb
+++ b/plugins/commands/serve/mappers/known_types.rb
@@ -3,21 +3,8 @@ require "google/protobuf/well_known_types"
 module VagrantPlugins
   module CommandServe
     class Mappers
-      # class KnownTypes < Mapper
-      #   def initialize
-      #     inputs = [].tap do |i|
-      #       i << Input.new(type: Google::Protobuf::Value)
-      #     end
-      #     super(inputs: inputs, output: Object, func: method(:converter))
-      #   end
-
-      #   def converter(proto)
-      #     proto.to_ruby
-      #   end
-      # end
-
       [NilClass, Numeric, String, TrueClass, FalseClass,
-        Struct, Hash, Google::Protobuf::ListValue, Array].each do |type|
+        Struct, Google::Protobuf::ListValue].each do |type|
         Class.new(Mapper).class_eval("
           def self.name
             '#{type.name}ToProto'
@@ -40,6 +27,90 @@ module VagrantPlugins
           end
         ")
       end
+
+      class HashToProto < Mapper
+        def initialize
+          super(
+            inputs: [
+              Input.new(type: Hash),
+              Input.new(type: Mappers),
+            ],
+            output: SDK::Args::Hash,
+            func: method(:converter),
+          )
+        end
+
+        def converter(hash, mapper)
+          fields = Hash.new.tap do |f|
+            hash.each_pair do |k, v|
+              r = mapper.map(v, to: Google::Protobuf::Any)
+              f[k] = r
+            end
+          end
+          SDK::Args::Hash.new(fields: fields)
+        end
+      end
+
+      class HashFromProto < Mapper
+        def initialize
+          super(
+            inputs: [
+              Input.new(type: SDK::Args::Hash),
+              Input.new(type: Mappers)
+            ],
+            output: Hash,
+            func: method(:converter),
+          )
+        end
+
+        def converter(proto, mapper)
+          Hash.new.tap do |result|
+            proto.fields.each_pair do |k, v|
+              r = mapper.map(v)
+              result[k.to_s] = r
+            end
+          end
+        end
+      end
+
+      class ArrayToProto < Mapper
+        def initialize
+          super(
+            inputs: [
+              Input.new(type: Array),
+              Input.new(type: Mappers),
+            ],
+            output: SDK::Args::Array,
+            func: method(:converter),
+          )
+        end
+
+        def converter(array, mapper)
+          r = array.map do |v|
+            mapper.map(v, to: Google::Protobuf::Any)
+          end
+          SDK::Args::Array.new(list: r)
+        end
+      end
+
+      class ArrayFromProto < Mapper
+        def initialize
+          super(
+            inputs: [
+              Input.new(type: SDK::Args::Array),
+              Input.new(type: Mappers),
+            ],
+            output: Array,
+            func: method(:converter),
+          )
+        end
+
+        def converter(proto, mapper)
+          proto.list.map do |v|
+            mapper.map(v)
+          end
+        end
+      end
     end
   end
 end