diff --git a/lib/isn.ex b/lib/isn.ex
index 63c3459..0b7d5c2 100644
--- a/lib/isn.ex
+++ b/lib/isn.ex
@@ -39,8 +39,7 @@ defmodule ISN do
       end
   """
 
-  def init(parameters, _opts),
-    do: parameters
+  def init(opts) when opts in [:copy, :reference], do: opts
 
   def matching(_),
     do: Enum.zip(Stream.cycle([:type]), @isn)
@@ -48,11 +47,25 @@ defmodule ISN do
   def format(_),
     do: :text
 
-  def encode(%TypeInfo{type: type}, binary, _types, _opts) when type in @isn,
-    do: binary
+  def encode(opts) do
+    quote do
+      thing ->
+        [<<IO.iodata_length(thing) :: int32>> | thing]
+    end
+  end
 
-  def decode(%TypeInfo{type: type}, binary, _types, _opts) when type in @isn,
-    do: binary
+  def decode(:copy) do
+    quote do
+      <<len :: int32, thing::binary-size(len)>> ->
+        :binary.copy(thing)
+    end
+  end
+  def decode(:reference) do
+    quote do
+      <<len :: int32, thing::binary-size(len)>> ->
+        thing
+    end
+  end
 end
 
 # Generate Ecto.Type modules for all supported data types in the `isn`
diff --git a/mix.lock b/mix.lock
index 3941fd4..0bc63bd 100644
--- a/mix.lock
+++ b/mix.lock
@@ -1,11 +1,11 @@
 %{"bunt": {:hex, :bunt, "0.1.6", "5d95a6882f73f3b9969fdfd1953798046664e6f77ec4e486e6fafc7caad97c6f", [:mix], []},
-  "connection": {:hex, :connection, "1.0.3", "3145f7416be3df248a4935f24e3221dc467c1e3a158d62015b35bd54da365786", [:mix], []},
-  "credo": {:hex, :credo, "0.4.5", "5c5daaf50a2a96068c0f21b6fbd382d206702efa8836a946eeab0b8ac25f5f22", [:mix], [{:bunt, "~> 0.1.6", [hex: :bunt, optional: false]}]},
-  "db_connection": {:hex, :db_connection, "1.0.0-rc.3", "d9ceb670fe300271140af46d357b669983cd16bc0d01206d7d3222dde56cf038", [:mix], [{:sbroker, "~> 1.0.0-beta.3", [hex: :sbroker, optional: true]}, {:poolboy, "~> 1.5", [hex: :poolboy, optional: true]}, {:connection, "~> 1.0.2", [hex: :connection, optional: false]}]},
-  "decimal": {:hex, :decimal, "1.1.2", "79a769d4657b2d537b51ef3c02d29ab7141d2b486b516c109642d453ee08e00c", [:mix], []},
-  "earmark": {:hex, :earmark, "1.0.1", "2c2cd903bfdc3de3f189bd9a8d4569a075b88a8981ded9a0d95672f6e2b63141", [:mix], []},
-  "ecto": {:hex, :ecto, "2.0.2", "b02331c1f20bbe944dbd33c8ecd8f1ccffecc02e344c4471a891baf3a25f5406", [:mix], [{:poison, "~> 1.5 or ~> 2.0", [hex: :poison, optional: true]}, {:sbroker, "~> 1.0-beta", [hex: :sbroker, optional: true]}, {:mariaex, "~> 0.7.7", [hex: :mariaex, optional: true]}, {:postgrex, "~> 0.11.2", [hex: :postgrex, optional: true]}, {:db_connection, "~> 1.0-rc.2", [hex: :db_connection, optional: true]}, {:decimal, "~> 1.0", [hex: :decimal, optional: false]}, {:poolboy, "~> 1.5", [hex: :poolboy, optional: false]}]},
+  "connection": {:hex, :connection, "1.0.4", "a1cae72211f0eef17705aaededacac3eb30e6625b04a6117c1b2db6ace7d5976", [:mix], []},
+  "credo": {:hex, :credo, "0.5.3", "0c405b36e7651245a8ed63c09e2d52c2e2b89b6d02b1570c4d611e0fcbecf4a2", [:mix], [{:bunt, "~> 0.1.6", [hex: :bunt, optional: false]}]},
+  "db_connection": {:hex, :db_connection, "1.1.0", "b2b88db6d7d12f99997b584d09fad98e560b817a20dab6a526830e339f54cdb3", [:mix], [{:connection, "~> 1.0.2", [hex: :connection, optional: false]}, {:poolboy, "~> 1.5", [hex: :poolboy, optional: true]}, {:sbroker, "~> 1.0", [hex: :sbroker, optional: true]}]},
+  "decimal": {:hex, :decimal, "1.3.1", "157b3cedb2bfcb5359372a7766dd7a41091ad34578296e951f58a946fcab49c6", [:mix], []},
+  "earmark": {:hex, :earmark, "1.0.3", "89bdbaf2aca8bbb5c97d8b3b55c5dd0cff517ecc78d417e87f1d0982e514557b", [:mix], []},
+  "ecto": {:hex, :ecto, "2.1.3", "ffb24e150b519a4c0e4c84f9eabc8587199389bc499195d5d1a93cd3b2d9a045", [:mix], [{:db_connection, "~> 1.1", [hex: :db_connection, optional: true]}, {:decimal, "~> 1.2", [hex: :decimal, optional: false]}, {:mariaex, "~> 0.8.0", [hex: :mariaex, optional: true]}, {:poison, "~> 2.2 or ~> 3.0", [hex: :poison, optional: true]}, {:poolboy, "~> 1.5", [hex: :poolboy, optional: false]}, {:postgrex, "~> 0.13.0", [hex: :postgrex, optional: true]}, {:sbroker, "~> 1.0", [hex: :sbroker, optional: true]}]},
   "eh": {:hex, :eh, "0.2.0"},
-  "ex_doc": {:hex, :ex_doc, "0.13.0", "aa2f8fe4c6136a2f7cfc0a7e06805f82530e91df00e2bff4b4362002b43ada65", [:mix], [{:earmark, "~> 1.0", [hex: :earmark, optional: false]}]},
+  "ex_doc": {:hex, :ex_doc, "0.14.5", "c0433c8117e948404d93ca69411dd575ec6be39b47802e81ca8d91017a0cf83c", [:mix], [{:earmark, "~> 1.0", [hex: :earmark, optional: false]}]},
   "poolboy": {:hex, :poolboy, "1.5.1", "6b46163901cfd0a1b43d692657ed9d7e599853b3b21b95ae5ae0a777cf9b6ca8", [:rebar], []},
-  "postgrex": {:hex, :postgrex, "0.11.2", "139755c1359d3c5c6d6e8b1ea72556d39e2746f61c6ddfb442813c91f53487e8", [:mix], [{:connection, "~> 1.0", [hex: :connection, optional: false]}, {:db_connection, "~> 1.0-rc", [hex: :db_connection, optional: false]}, {:decimal, "~> 1.0", [hex: :decimal, optional: false]}]}}
+  "postgrex": {:hex, :postgrex, "0.13.0", "e101ab47d0725955c5c8830ae8812412992e02e4bd9db09e17abb0a5d82d09c7", [:mix], [{:connection, "~> 1.0", [hex: :connection, optional: false]}, {:db_connection, "~> 1.1", [hex: :db_connection, optional: false]}, {:decimal, "~> 1.0", [hex: :decimal, optional: false]}]}}
diff --git a/test/test_helper.exs b/test/test_helper.exs
index b8db981..5d4e866 100644
--- a/test/test_helper.exs
+++ b/test/test_helper.exs
@@ -1,21 +1,32 @@
 ExUnit.start()
+Postgrex.Types.define(
+  ISN.PostgrexTypes,
+  [{ISN, :reference}],
+  [])
 
 defmodule ISN.TestHelper do
   def conn_options do
     db_options = [
       sync_connect: true,
       hostname: "localhost",
+      types: ISN.PostgrexTypes,
       database: "isn_test"]
 
     db_user = System.get_env("DATABASE_POSTGRESQL_USERNAME")
     db_pass = System.get_env("DATABASE_POSTGRESQL_PASSWORD")
 
     db_options =
-      if db_user, do: db_options = Dict.put(db_options, :username, db_user),
-      else: db_options
+      if db_user do
+        Map.put(db_options, :username, db_user)
+      else
+        db_options
+      end
     db_options =
-      if db_pass, do: db_options = Dict.put(db_options, :password, db_pass),
-      else: db_options
+      if db_pass do
+        Map.put(db_options, :password, db_pass)
+      else
+        db_options
+      end
 
     db_options
   end