diff --git a/README.md b/README.md
index 2770de4..1181432 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,6 @@
 
 Yesql is an Elixir library for _using_ SQL.
 
-
 ## Rationale
 
 You're writing Elixir You need to write some SQL.
diff --git a/config/config.exs b/config/config.exs
new file mode 100644
index 0000000..3769fe7
--- /dev/null
+++ b/config/config.exs
@@ -0,0 +1,19 @@
+use Mix.Config
+
+case Mix.env() do
+  :test ->
+    config :yesql, ecto_repos: [YesqlTest.Repo]
+
+    config :yesql, YesqlTest.Repo, adapter: Ecto.Adapters.Postgres
+
+    config :yesql, YesqlTest.Repo,
+      username: "postgres",
+      password: "postgres",
+      database: "yesql_test",
+      hostname: "localhost"
+
+    config :logger, level: :info
+
+  _ ->
+    :ok
+end
diff --git a/lib/yesql.ex b/lib/yesql.ex
index 8a43971..0dfface 100644
--- a/lib/yesql.ex
+++ b/lib/yesql.ex
@@ -1,11 +1,24 @@
 defmodule Yesql do
   @moduledoc """
-  Documentation for Yesql.
+
+      defmodule Query do
+        use Yesql, driver: Postgrex, conn: MyApp.ConnectionPool
+
+        Yesql.defquery("some/where/select_users_by_country.sql")
+      end
+
+      Query.users_by_country(country_code: "gbr")
+      # => {:ok, [%{name: "Louis", country_code: "gbr"}]}
+
+  ## Supported drivers
+
+  - `Postgrex`
+  - `Ecto`, for which `conn` is an Ecto repo.
   """
 
   alias __MODULE__.{NoDriver, UnknownDriver, MissingParam}
 
-  @supported_drivers [Postgrex]
+  @supported_drivers [Postgrex, Ecto]
 
   defmacro __using__(opts) do
     quote bind_quoted: binding() do
@@ -90,6 +103,12 @@ defmodule Yesql do
     end
   end
 
+  if Code.ensure_compiled?(Ecto) do
+    defp exec_for_driver(repo, Ecto, sql, param_list) do
+      Ecto.Adapters.SQL.query(repo, sql, param_list)
+    end
+  end
+
   defp exec_for_driver(_, driver, _, _) do
     raise UnknownDriver.exception(driver)
   end
diff --git a/lib/yesql/exceptions.ex b/lib/yesql/exceptions.ex
index bce9103..abfaa87 100644
--- a/lib/yesql/exceptions.ex
+++ b/lib/yesql/exceptions.ex
@@ -6,6 +6,7 @@ defmodule Yesql.MissingParam do
     msg = """
     Required parameter `:#{param}` not given
     """
+
     %__MODULE__{message: msg}
   end
 end
@@ -18,6 +19,7 @@ defmodule Yesql.UnknownDriver do
     msg = """
     Unknown database driver #{driver}
     """
+
     %__MODULE__{message: msg}
   end
 end
diff --git a/mix.exs b/mix.exs
index 3a41916..d881ff3 100644
--- a/mix.exs
+++ b/mix.exs
@@ -4,9 +4,10 @@ defmodule Yesql.Mixfile do
   def project do
     [
       app: :yesql,
-      version: "0.2.0",
+      version: "0.3.0",
       elixir: "~> 1.5",
       start_permanent: Mix.env() == :prod,
+      elixirc_paths: elixirc_paths(Mix.env()),
       deps: deps(),
       name: "Yesql",
       description: "Using plain old SQL to query databases",
@@ -20,17 +21,32 @@ defmodule Yesql.Mixfile do
   end
 
   def application do
-    [extra_applications: []]
+    case Mix.env() do
+      :test ->
+        [
+          mod: {YesqlTest.Application, []},
+          extra_applications: [:logger, :runtime_tools]
+        ]
+
+      _ ->
+        [extra_applications: []]
+    end
   end
 
+  defp elixirc_paths(:test), do: ["lib", "test/support"]
+  defp elixirc_paths(_), do: ["lib"]
+
   defp deps do
     [
       # Postgresql driver
       {:postgrex, "~> 0.12", optional: true},
+      # Database abstraction
+      {:ecto, "~> 2.0", optional: true},
+
       # Automatic testing tool
       {:mix_test_watch, ">= 0.0.0", only: :dev},
       # Documentation generator
-      {:ex_doc, "~> 0.18.0", only: :dev}
+      {:ex_doc, "~> 0.18", only: :dev}
     ]
   end
 end
diff --git a/mix.lock b/mix.lock
index 9b559f0..2ebbacb 100644
--- a/mix.lock
+++ b/mix.lock
@@ -1,10 +1,16 @@
 %{
-  "connection": {:hex, :connection, "1.0.4", "a1cae72211f0eef17705aaededacac3eb30e6625b04a6117c1b2db6ace7d5976", [], [], "hexpm"},
-  "db_connection": {:hex, :db_connection, "1.1.2", "2865c2a4bae0714e2213a0ce60a1b12d76a6efba0c51fbda59c9ab8d1accc7a8", [], [{:connection, "~> 1.0.2", [hex: :connection, repo: "hexpm", optional: false]}, {:poolboy, "~> 1.5", [hex: :poolboy, repo: "hexpm", optional: true]}, {:sbroker, "~> 1.0", [hex: :sbroker, repo: "hexpm", optional: true]}], "hexpm"},
-  "decimal": {:hex, :decimal, "1.4.1", "ad9e501edf7322f122f7fc151cce7c2a0c9ada96f2b0155b8a09a795c2029770", [], [], "hexpm"},
-  "earmark": {:hex, :earmark, "1.2.4", "99b637c62a4d65a20a9fb674b8cffb8baa771c04605a80c911c4418c69b75439", [:mix], [], "hexpm"},
-  "ex_doc": {:hex, :ex_doc, "0.18.1", "37c69d2ef62f24928c1f4fdc7c724ea04aecfdf500c4329185f8e3649c915baf", [:mix], [{:earmark, "~> 1.1", [hex: :earmark, repo: "hexpm", optional: false]}], "hexpm"},
-  "fs": {:hex, :fs, "0.9.2", "ed17036c26c3f70ac49781ed9220a50c36775c6ca2cf8182d123b6566e49ec59", [], [], "hexpm"},
-  "mix_test_watch": {:hex, :mix_test_watch, "0.5.0", "2c322d119a4795c3431380fca2bca5afa4dc07324bd3c0b9f6b2efbdd99f5ed3", [], [{:fs, "~> 0.9.1", [hex: :fs, repo: "hexpm", optional: false]}], "hexpm"},
-  "postgrex": {:hex, :postgrex, "0.13.3", "c277cfb2a9c5034d445a722494c13359e361d344ef6f25d604c2353185682bfc", [], [{:connection, "~> 1.0", [hex: :connection, repo: "hexpm", optional: false]}, {:db_connection, "~> 1.1", [hex: :db_connection, repo: "hexpm", optional: false]}, {:decimal, "~> 1.0", [hex: :decimal, repo: "hexpm", optional: false]}], "hexpm"},
+  "connection": {:hex, :connection, "1.0.4", "a1cae72211f0eef17705aaededacac3eb30e6625b04a6117c1b2db6ace7d5976", [:mix], [], "hexpm"},
+  "db_connection": {:hex, :db_connection, "1.1.3", "89b30ca1ef0a3b469b1c779579590688561d586694a3ce8792985d4d7e575a61", [:mix], [{:connection, "~> 1.0.2", [hex: :connection, repo: "hexpm", optional: false]}, {:poolboy, "~> 1.5", [hex: :poolboy, repo: "hexpm", optional: true]}, {:sbroker, "~> 1.0", [hex: :sbroker, repo: "hexpm", optional: true]}], "hexpm"},
+  "decimal": {:hex, :decimal, "1.5.0", "b0433a36d0e2430e3d50291b1c65f53c37d56f83665b43d79963684865beab68", [:mix], [], "hexpm"},
+  "earmark": {:hex, :earmark, "1.2.5", "4d21980d5d2862a2e13ec3c49ad9ad783ffc7ca5769cf6ff891a4553fbaae761", [:mix], [], "hexpm"},
+  "ecto": {:hex, :ecto, "2.2.10", "e7366dc82f48f8dd78fcbf3ab50985ceeb11cb3dc93435147c6e13f2cda0992e", [:mix], [{:db_connection, "~> 1.1", [hex: :db_connection, repo: "hexpm", optional: true]}, {:decimal, "~> 1.2", [hex: :decimal, repo: "hexpm", optional: false]}, {:mariaex, "~> 0.8.0", [hex: :mariaex, repo: "hexpm", optional: true]}, {:poison, "~> 2.2 or ~> 3.0", [hex: :poison, repo: "hexpm", optional: true]}, {:poolboy, "~> 1.5", [hex: :poolboy, repo: "hexpm", optional: false]}, {:postgrex, "~> 0.13.0", [hex: :postgrex, repo: "hexpm", optional: true]}, {:sbroker, "~> 1.0", [hex: :sbroker, repo: "hexpm", optional: true]}], "hexpm"},
+  "ex_doc": {:hex, :ex_doc, "0.19.0", "e22b6434373b4870ea77b24df069dbac7002c1f483615e9ebfc0c37497e1c75c", [:mix], [{:earmark, "~> 1.1", [hex: :earmark, repo: "hexpm", optional: false]}, {:makeup_elixir, "~> 0.7", [hex: :makeup_elixir, repo: "hexpm", optional: false]}], "hexpm"},
+  "file_system": {:hex, :file_system, "0.2.6", "fd4dc3af89b9ab1dc8ccbcc214a0e60c41f34be251d9307920748a14bf41f1d3", [:mix], [], "hexpm"},
+  "fs": {:hex, :fs, "0.9.2", "ed17036c26c3f70ac49781ed9220a50c36775c6ca2cf8182d123b6566e49ec59", [:rebar], [], "hexpm"},
+  "makeup": {:hex, :makeup, "0.5.1", "966c5c2296da272d42f1de178c1d135e432662eca795d6dc12e5e8787514edf7", [:mix], [{:nimble_parsec, "~> 0.2.2", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm"},
+  "makeup_elixir": {:hex, :makeup_elixir, "0.8.0", "1204a2f5b4f181775a0e456154830524cf2207cf4f9112215c05e0b76e4eca8b", [:mix], [{:makeup, "~> 0.5.0", [hex: :makeup, repo: "hexpm", optional: false]}, {:nimble_parsec, "~> 0.2.2", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm"},
+  "mix_test_watch": {:hex, :mix_test_watch, "0.8.0", "acf97da2abc66532e7dc1aa66a5d6c9fc4442d7992d5d7eb4faeaeb964c2580e", [:mix], [{:file_system, "~> 0.2.1 or ~> 0.3", [hex: :file_system, repo: "hexpm", optional: false]}], "hexpm"},
+  "nimble_parsec": {:hex, :nimble_parsec, "0.2.2", "d526b23bdceb04c7ad15b33c57c4526bf5f50aaa70c7c141b4b4624555c68259", [:mix], [], "hexpm"},
+  "poolboy": {:hex, :poolboy, "1.5.1", "6b46163901cfd0a1b43d692657ed9d7e599853b3b21b95ae5ae0a777cf9b6ca8", [:rebar], [], "hexpm"},
+  "postgrex": {:hex, :postgrex, "0.13.5", "3d931aba29363e1443da167a4b12f06dcd171103c424de15e5f3fc2ba3e6d9c5", [:mix], [{:connection, "~> 1.0", [hex: :connection, repo: "hexpm", optional: false]}, {:db_connection, "~> 1.1", [hex: :db_connection, repo: "hexpm", optional: false]}, {:decimal, "~> 1.0", [hex: :decimal, repo: "hexpm", optional: false]}], "hexpm"},
 }
diff --git a/test/support/support.ex b/test/support/support.ex
new file mode 100644
index 0000000..240f31c
--- /dev/null
+++ b/test/support/support.ex
@@ -0,0 +1,13 @@
+defmodule YesqlTest.Application do
+  use Application
+
+  def start(_type, _args) do
+    Application.ensure_all_started(:ecto)
+    Application.ensure_all_started(:postgrex)
+    Supervisor.start_link([YesqlTest.Repo], strategy: :one_for_one, name: Blondie.Supervisor)
+  end
+end
+
+defmodule YesqlTest.Repo do
+  use Ecto.Repo, otp_app: :yesql
+end
diff --git a/test/yesql_test.exs b/test/yesql_test.exs
index a610100..e773cb5 100644
--- a/test/yesql_test.exs
+++ b/test/yesql_test.exs
@@ -3,6 +3,25 @@ defmodule YesqlTest do
   doctest Yesql
   import TestHelper
 
+  defmodule Query do
+    use Yesql, driver: Postgrex
+
+    Yesql.defquery("test/sql/select_older_cats.sql")
+    Yesql.defquery("test/sql/insert_cat.sql")
+  end
+
+  defmodule QueryConn do
+    use Yesql, driver: Postgrex, conn: YesqlTest.Postgrex
+    Yesql.defquery("test/sql/select_older_cats.sql")
+    Yesql.defquery("test/sql/insert_cat.sql")
+  end
+
+  defmodule QueryEcto do
+    use Yesql, driver: Ecto, conn: YesqlTest.Repo
+    Yesql.defquery("test/sql/select_older_cats.sql")
+    Yesql.defquery("test/sql/insert_cat.sql")
+  end
+
   setup_all [:new_postgrex_connection, :create_cats_postgres_table]
 
   describe "parse/1" do
@@ -112,31 +131,28 @@ defmodule YesqlTest do
   describe "defquery/2" do
     setup [:truncate_postgres_cats]
 
-    defmodule Query do
-      use Yesql, driver: Postgrex
-
-      Yesql.defquery("test/sql/select_older_cats.sql")
-      Yesql.defquery("test/sql/insert_cat.sql")
-    end
-
     test "query function is created" do
       refute function_exported?(Query, :select_older_cats, 1)
       assert function_exported?(Query, :select_older_cats, 2)
+
+      # The /1 arity function is called because conn isn't needed.
+      assert function_exported?(QueryConn, :select_older_cats, 1)
+      assert function_exported?(QueryConn, :select_older_cats, 2)
     end
 
     test "throws if map argument missing" do
       assert_raise Yesql.MissingParam, "Required parameter `:age` not given\n", fn ->
-        Query.select_older_cats(nil, %{})
+        QueryConn.select_older_cats(%{})
       end
     end
 
     test "throws if keyword argument missing" do
       assert_raise Yesql.MissingParam, "Required parameter `:age` not given\n", fn ->
-        Query.select_older_cats(nil, [])
+        QueryConn.select_older_cats(nil, [])
       end
     end
 
-    test "query exec", %{postgrex: conn} do
+    test "query exec with explicit conn", %{postgrex: conn} do
       assert Query.select_older_cats(conn, age: 5) == {:ok, []}
       assert Query.insert_cat(conn, age: 50) == {:ok, []}
       assert Query.select_older_cats(conn, age: 5) == {:ok, [%{age: 50, name: nil}]}
@@ -150,38 +166,8 @@ defmodule YesqlTest do
       assert Query.select_older_cats(conn, age: 5) ==
                {:ok, [%{age: 10, name: nil}, %{age: 50, name: nil}]}
     end
-  end
-
-  # TODO
-  # describe "defquery/2 with driver passed"
-
-  describe "defquery/2 with conn" do
-    setup [:truncate_postgres_cats]
-
-    defmodule QueryConn do
-      use Yesql, driver: Postgrex, conn: YesqlTest.Postgrex
-      Yesql.defquery("test/sql/select_older_cats.sql")
-      Yesql.defquery("test/sql/insert_cat.sql")
-    end
-
-    test "query function is created" do
-      assert function_exported?(QueryConn, :select_older_cats, 1)
-      assert function_exported?(QueryConn, :select_older_cats, 2)
-    end
 
-    test "throws if map argument missing" do
-      assert_raise Yesql.MissingParam, "Required parameter `:age` not given\n", fn ->
-        QueryConn.select_older_cats(%{})
-      end
-    end
-
-    test "throws if keyword argument missing" do
-      assert_raise Yesql.MissingParam, "Required parameter `:age` not given\n", fn ->
-        QueryConn.select_older_cats([])
-      end
-    end
-
-    test "query exec" do
+    test "query exec with implicit conn" do
       assert QueryConn.select_older_cats(age: 5) == {:ok, []}
       assert QueryConn.insert_cat(age: 50) == {:ok, []}
       assert QueryConn.select_older_cats(age: 5) == {:ok, [%{age: 50, name: nil}]}
@@ -195,5 +181,11 @@ defmodule YesqlTest do
       assert QueryConn.select_older_cats(age: 5) ==
                {:ok, [%{age: 10, name: nil}, %{age: 50, name: nil}]}
     end
+
+    test "query exec with Ecto driver" do
+      assert QueryEcto.select_older_cats(age: 5) == {:ok, []}
+      assert QueryEcto.insert_cat(age: 50) == {:ok, []}
+      assert QueryEcto.select_older_cats(age: 5) == {:ok, [%{age: 50, name: nil}]}
+    end
   end
 end