diff --git a/README.md b/README.md
index 80f428d..ed27809 100644
--- a/README.md
+++ b/README.md
@@ -11,6 +11,20 @@ This is not meant to generate data for your tests, if this is what
 you need, checkout [ecto_fixtures](https://github.com/dockyard/ecto_fixtures) or
 [ex_machina](https://github.com/thoughtbot/ex_machina) instead.
 
+## Compatible versions
+
+Version `0.3.0` or lower:
+
+* Elixir ~> `1.11.x` or lower.
+
+Version `0.4.0`:
+
+* Elixir ~> `1.13.x`.
+
+Version `0.5.0` or higher:
+
+* Elixir ~> `1.14.x` or higher.
+
 ## Installation
 
 Add `seedex` to your list of dependencies in `mix.exs`:
diff --git a/config/config.exs b/config/config.exs
index 12d81f3..ae29279 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -1,4 +1,4 @@
-use Mix.Config
+import Config
 
 config :seedex,
   ecto_repos: [Seedex.Repo],
@@ -8,6 +8,7 @@ config :seedex,
 config :seedex, Seedex.Repo,
   database: "seedex_test",
   username: "postgres",
+  password: "postgres",
   hostname: "localhost",
   pool: Ecto.Adapters.SQL.Sandbox
 
diff --git a/lib/mix/tasks/seedex.seed.ex b/lib/mix/tasks/seedex.seed.ex
index 2ed8571..477fe36 100644
--- a/lib/mix/tasks/seedex.seed.ex
+++ b/lib/mix/tasks/seedex.seed.ex
@@ -24,7 +24,10 @@ defmodule Mix.Tasks.Seedex.Seed do
 
   @doc false
   def run(args) do
-    {opts, _, _} = OptionParser.parse(args, switches: [env: :string, seeds_path: :string, debug: :boolean, quiet: :boolean])
+    {opts, _, _} =
+      OptionParser.parse(args,
+        switches: [env: :string, seeds_path: :string, debug: :boolean, quiet: :boolean]
+      )
 
     if opts[:debug] do
       Logger.configure(level: :debug)
@@ -35,20 +38,20 @@ defmodule Mix.Tasks.Seedex.Seed do
     Mix.Task.run("app.start", [])
 
     seeds_path = Keyword.get(opts, :seeds_path, default_path())
-    env = Keyword.get(opts, :env, to_string(Mix.env))
+    env = Keyword.get(opts, :env, to_string(Mix.env()))
 
     unless File.dir?(seeds_path) do
-      Mix.raise """
+      Mix.raise("""
       seeeds_path is not a directory, create priv/repo/seeds or configure in :seedex configuration
-      """
+      """)
     end
 
     seeds_path
     |> seeds_files(env)
-    |> Enum.each(&Code.load_file(&1))
+    |> Enum.each(&Code.compile_file(&1))
 
     unless opts[:quiet] do
-      Mix.shell.info("Database has been populated with seeds from #{seeds_path}")
+      Mix.shell().info("Database has been populated with seeds from #{seeds_path}")
     end
   end
 
@@ -60,7 +63,7 @@ defmodule Mix.Tasks.Seedex.Seed do
   defp exs_files(path) do
     path
     |> Path.join("*.exs")
-    |> Path.wildcard
+    |> Path.wildcard()
   end
 
   defp default_path do
diff --git a/lib/seedex.ex b/lib/seedex.ex
index 4706e3f..c8b9044 100644
--- a/lib/seedex.ex
+++ b/lib/seedex.ex
@@ -34,7 +34,8 @@ defmodule Seedex do
     ]
     ```
   """
-  @spec seed(module :: atom, constraints :: [atom], data :: [map], process :: (struct -> struct)) :: :ok
+  @spec seed(module :: atom, constraints :: [atom], data :: [map], process :: (struct -> struct)) ::
+          :ok
   def seed(module, constraints \\ [:id], data \\ [], process \\ nil) do
     dispatch_seed(module, constraints, data, process, update: true)
   end
@@ -42,7 +43,12 @@ defmodule Seedex do
   @doc """
   Same as `seed/3` but does not update the record if it already exists
   """
-  @spec seed_once(module :: atom, constraints :: [atom], data :: (struct -> struct) | [map], process :: (struct -> struct)) :: :ok
+  @spec seed_once(
+          module :: atom,
+          constraints :: [atom],
+          data :: (struct -> struct) | [map],
+          process :: (struct -> struct)
+        ) :: :ok
   def seed_once(module, constraints \\ [:id], data \\ [], process \\ nil) do
     dispatch_seed(module, constraints, data, process, update: false)
   end
@@ -52,39 +58,48 @@ defmodule Seedex do
   # arguments were all pased
   defp dispatch_seed(module, constraints, data, func, opts) when is_function(func, 1),
     do: do_seed(module, constraints, data, func, opts)
+
   # 3 arguments passed
   defp dispatch_seed(module, [h | t], data, nil, opts) when is_atom(h) and is_list(data),
     do: do_seed(module, [h | t], data, &identity/1, opts)
+
   defp dispatch_seed(module, [h | t], func, nil, opts) when is_atom(h) and is_function(func, 1),
     do: do_seed(module, [h | t], [], func, opts)
+
   defp dispatch_seed(module, [h | t], func, nil, opts) when is_map(h) and is_function(func, 1),
     do: do_seed(module, [:id], [h | t], func, opts)
+
   # 2 arguments passed
   defp dispatch_seed(module, func, [], nil, opts) when is_function(func, 1),
     do: do_seed(module, [:id], [], func, opts)
+
   defp dispatch_seed(module, [h | t], [], nil, opts) when is_map(h),
     do: do_seed(module, [:id], [h | t], &identity/1, opts)
+
   defp dispatch_seed(_module, _constraints, _data, _func, _opts),
-    do: raise ArgumentError, "invalid arguments to seed"
+    do: raise(ArgumentError, "invalid arguments to seed")
 
-  defp do_seed(module, constraints, [], process, opts), do:
-    do_seed(module, constraints, [%{}], process, opts)
+  defp do_seed(module, constraints, [], process, opts),
+    do: do_seed(module, constraints, [%{}], process, opts)
 
   defp do_seed(module, constraints, data, process, opts) do
-    Enum.each data, fn record ->
+    Enum.each(data, fn record ->
       record = struct(module, record) |> process.()
       insert_seed(module, record, constraints, opts)
-    end
+    end)
   end
 
   defp insert_seed(module, record, constraints, opts) do
     existing = fetch_record(module, record, constraints)
+
     cond do
       existing && opts[:update] ->
         update_record(record, existing)
+
       !existing ->
         Logger.debug("Inserting record #{inspect(record)}")
         repo().insert(record)
+
       true ->
         :ok
     end
@@ -94,6 +109,7 @@ defmodule Seedex do
     case make_query(record, constraints) do
       [] ->
         nil
+
       query ->
         repo().get_by(module, query)
     end
@@ -101,7 +117,7 @@ defmodule Seedex do
 
   defp make_query(record, constraints) do
     constraints
-    |> Enum.map(& {&1, Map.fetch!(record, &1)})
+    |> Enum.map(&{&1, Map.fetch!(record, &1)})
     |> Enum.reject(fn {_k, v} -> is_nil(v) end)
   end
 
@@ -113,18 +129,23 @@ defmodule Seedex do
 
   defp make_changeset(record, existing) do
     {changeset, changes} = {Ecto.Changeset.change(existing), Map.from_struct(record)}
-    Enum.reduce changes, changeset, fn
+
+    Enum.reduce(changes, changeset, fn
       {_key, %Ecto.Association.NotLoaded{}}, changeset ->
         changeset
+
       {_key, nil}, changeset ->
         changeset
+
       {key, _value}, changeset when key in ["__meta__", :__meta__] ->
         changeset
+
       {key, %Ecto.Association.BelongsTo{} = assoc}, changeset ->
         Ecto.Changeset.put_assoc(changeset, key, assoc)
+
       {key, value}, changeset ->
         Ecto.Changeset.put_change(changeset, key, value)
-    end
+    end)
   end
 
   defp repo do
diff --git a/mix.exs b/mix.exs
index ddaca29..03a437e 100644
--- a/mix.exs
+++ b/mix.exs
@@ -1,39 +1,46 @@
 defmodule Seedex.Mixfile do
   use Mix.Project
 
-  @version "0.3.0"
+  @version "0.3.1"
 
   def project do
-    [app: :seedex,
-     version: @version,
-     elixir: "~> 1.1",
-     description: "Seed data generation for Ecto",
-     source_url: "https://github.com/danhper/seedex",
-     elixirc_paths: elixirc_paths(Mix.env),
-     build_embedded: Mix.env == :prod,
-     start_permanent: Mix.env == :prod,
-     package: package(),
-     deps: deps(),
-     docs: [source_ref: "#{@version}", extras: ["README.md"], main: "readme"]]
+    [
+      app: :seedex,
+      version: @version,
+      elixir: "~> 1.13",
+      description: "Seed data generation for Ecto",
+      source_url: "https://github.com/danhper/seedex",
+      elixirc_paths: elixirc_paths(Mix.env()),
+      build_embedded: Mix.env() == :prod,
+      start_permanent: Mix.env() == :prod,
+      package: package(),
+      deps: deps(),
+      docs: [source_ref: "#{@version}", extras: ["README.md"], main: "readme"]
+    ]
   end
 
   def application do
-    [applications: applications(Mix.env),
-     description: 'Seed data generation for Ecto']
+    [
+      extra_applications: [:ecto],
+      applications: applications(Mix.env()),
+      description: 'Seed data generation for Ecto'
+    ]
   end
 
   defp applications(:test), do: applications(:all) ++ [:ecto, :postgrex]
-  defp applications(_all),  do: [:logger]
+  defp applications(_all), do: [:logger]
 
   defp elixirc_paths(:test), do: ["lib", "test/support"]
-  defp elixirc_paths(_all),  do: ["lib"]
+  defp elixirc_paths(_all), do: ["lib"]
 
   defp deps do
-    [{:ecto, "~> 1.1 or ~> 2.1 or ~> 3.0"},
-     {:ecto_sql, "~> 3.0"},
-     {:postgrex, "~> 0.13", only: [:test]},
-     {:earmark,   "~> 1.0", only: :docs},
-     {:ex_doc,    "~> 0.14", only: :docs}]
+    [
+      {:ecto, "~> 3.9"},
+      {:ecto_sql, "~> 3.9"},
+      {:postgrex, "~> 0.16.1", only: [:test]},
+      {:earmark, "~> 1.4.20", only: :docs},
+      {:ex_doc, "~> 0.14", only: :docs}
+    ]
   end
 
   defp package do
diff --git a/mix.lock b/mix.lock
index d14ead0..ca81cb0 100644
--- a/mix.lock
+++ b/mix.lock
@@ -1,15 +1,16 @@
 %{
-  "connection": {:hex, :connection, "1.0.4", "a1cae72211f0eef17705aaededacac3eb30e6625b04a6117c1b2db6ace7d5976", [:mix], [], "hexpm"},
-  "db_connection": {:hex, :db_connection, "2.0.6", "bde2f85d047969c5b5800cb8f4b3ed6316c8cb11487afedac4aa5f93fd39abfa", [:mix], [{:connection, "~> 1.0.2", [hex: :connection, repo: "hexpm", optional: false]}], "hexpm"},
-  "decimal": {:hex, :decimal, "1.7.0", "30d6b52c88541f9a66637359ddf85016df9eb266170d53105f02e4a67e00c5aa", [:mix], [], "hexpm"},
-  "earmark": {:hex, :earmark, "1.3.2", "b840562ea3d67795ffbb5bd88940b1bed0ed9fa32834915125ea7d02e35888a5", [:mix], [], "hexpm"},
-  "ecto": {:hex, :ecto, "3.1.1", "d6677f95f1e0bd39bc3db3db6b23a59977cb154ed2cceec69a56becd805128be", [:mix], [{:decimal, "~> 1.6", [hex: :decimal, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}], "hexpm"},
-  "ecto_sql": {:hex, :ecto_sql, "3.1.1", "af2458e7a467d75a6389e1d4ebfb57c328ccc684d6ee52145f7b34e94efb5fc4", [:mix], [{:db_connection, "~> 2.0", [hex: :db_connection, repo: "hexpm", optional: false]}, {:ecto, "~> 3.1.0", [hex: :ecto, repo: "hexpm", optional: false]}, {:mariaex, "~> 0.9.1", [hex: :mariaex, repo: "hexpm", optional: true]}, {:myxql, "~> 0.2.0", [hex: :myxql, repo: "hexpm", optional: true]}, {:postgrex, "~> 0.14.0", [hex: :postgrex, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm"},
-  "ex_doc": {:hex, :ex_doc, "0.20.2", "1bd0dfb0304bade58beb77f20f21ee3558cc3c753743ae0ddbb0fd7ba2912331", [:mix], [{:earmark, "~> 1.3", [hex: :earmark, repo: "hexpm", optional: false]}, {:makeup_elixir, "~> 0.10", [hex: :makeup_elixir, repo: "hexpm", optional: false]}], "hexpm"},
-  "makeup": {:hex, :makeup, "0.8.0", "9cf32aea71c7fe0a4b2e9246c2c4978f9070257e5c9ce6d4a28ec450a839b55f", [:mix], [{:nimble_parsec, "~> 0.5.0", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm"},
-  "makeup_elixir": {:hex, :makeup_elixir, "0.13.0", "be7a477997dcac2e48a9d695ec730b2d22418292675c75aa2d34ba0909dcdeda", [:mix], [{:makeup, "~> 0.8", [hex: :makeup, repo: "hexpm", optional: false]}], "hexpm"},
-  "nimble_parsec": {:hex, :nimble_parsec, "0.5.0", "90e2eca3d0266e5c53f8fbe0079694740b9c91b6747f2b7e3c5d21966bba8300", [:mix], [], "hexpm"},
+  "connection": {:hex, :connection, "1.1.0", "ff2a49c4b75b6fb3e674bfc5536451607270aac754ffd1bdfe175abe4a6d7a68", [:mix], [], "hexpm", "722c1eb0a418fbe91ba7bd59a47e28008a189d47e37e0e7bb85585a016b2869c"},
+  "db_connection": {:hex, :db_connection, "2.4.3", "3b9aac9f27347ec65b271847e6baeb4443d8474289bd18c1d6f4de655b70c94d", [:mix], [{:connection, "~> 1.0", [hex: :connection, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "c127c15b0fa6cfb32eed07465e05da6c815b032508d4ed7c116122871df73c12"},
+  "decimal": {:hex, :decimal, "2.0.0", "a78296e617b0f5dd4c6caf57c714431347912ffb1d0842e998e9792b5642d697", [:mix], [], "hexpm", "34666e9c55dea81013e77d9d87370fe6cb6291d1ef32f46a1600230b1d44f577"},
+  "earmark": {:hex, :earmark, "1.4.20", "d5097b1c7417a03c73a2985fcf01c3f72192c427b8a498719737dca5273938cb", [:mix], [{:earmark_parser, "== 1.4.18", [hex: :earmark_parser, repo: "hexpm", optional: false]}], "hexpm", "7be744242dbde74c858279f4a65d9d31f37d163190d739340015c30038c1edb3"},
+  "earmark_parser": {:hex, :earmark_parser, "1.4.18", "e1b2be73eb08a49fb032a0208bf647380682374a725dfb5b9e510def8397f6f2", [:mix], [], "hexpm", "114a0e85ec3cf9e04b811009e73c206394ffecfcc313e0b346de0d557774ee97"},
+  "ecto": {:hex, :ecto, "3.9.2", "017db3bc786ff64271108522c01a5d3f6ba0aea5c84912cfb0dd73bf13684108", [:mix], [{:decimal, "~> 1.6 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "21466d5177e09e55289ac7eade579a642578242c7a3a9f91ad5c6583337a9d15"},
+  "ecto_sql": {:hex, :ecto_sql, "3.9.1", "9bd5894eecc53d5b39d0c95180d4466aff00e10679e13a5cfa725f6f85c03c22", [:mix], [{:db_connection, "~> 2.5 or ~> 2.4.1", [hex: :db_connection, repo: "hexpm", optional: false]}, {:ecto, "~> 3.9.0", [hex: :ecto, repo: "hexpm", optional: false]}, {:myxql, "~> 0.6.0", [hex: :myxql, repo: "hexpm", optional: true]}, {:postgrex, "~> 0.16.0 or ~> 1.0", [hex: :postgrex, repo: "hexpm", optional: true]}, {:tds, "~> 2.1.1 or ~> 2.2", [hex: :tds, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4.0 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "5fd470a4fff2e829bbf9dcceb7f3f9f6d1e49b4241e802f614de6b8b67c51118"},
+  "ex_doc": {:hex, :ex_doc, "0.20.2", "1bd0dfb0304bade58beb77f20f21ee3558cc3c753743ae0ddbb0fd7ba2912331", [:mix], [{:earmark, "~> 1.3", [hex: :earmark, repo: "hexpm", optional: false]}, {:makeup_elixir, "~> 0.10", [hex: :makeup_elixir, repo: "hexpm", optional: false]}], "hexpm", "8e24fc8ff9a50b9f557ff020d6c91a03cded7e59ac3e0eec8a27e771430c7d27"},
+  "makeup": {:hex, :makeup, "0.8.0", "9cf32aea71c7fe0a4b2e9246c2c4978f9070257e5c9ce6d4a28ec450a839b55f", [:mix], [{:nimble_parsec, "~> 0.5.0", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "5fbc8e549aa9afeea2847c0769e3970537ed302f93a23ac612602e805d9d1e7f"},
+  "makeup_elixir": {:hex, :makeup_elixir, "0.13.0", "be7a477997dcac2e48a9d695ec730b2d22418292675c75aa2d34ba0909dcdeda", [:mix], [{:makeup, "~> 0.8", [hex: :makeup, repo: "hexpm", optional: false]}], "hexpm", "adf0218695e22caeda2820eaba703fa46c91820d53813a2223413da3ef4ba515"},
+  "nimble_parsec": {:hex, :nimble_parsec, "0.5.0", "90e2eca3d0266e5c53f8fbe0079694740b9c91b6747f2b7e3c5d21966bba8300", [:mix], [], "hexpm", "5c040b8469c1ff1b10093d3186e2e10dbe483cd73d79ec017993fb3985b8a9b3"},
   "poolboy": {:hex, :poolboy, "1.5.1", "6b46163901cfd0a1b43d692657ed9d7e599853b3b21b95ae5ae0a777cf9b6ca8", [:rebar], [], "hexpm"},
-  "postgrex": {:hex, :postgrex, "0.14.2", "6680591bbce28d92f043249205e8b01b36cab9ef2a7911abc43649242e1a3b78", [:mix], [{:connection, "~> 1.0", [hex: :connection, repo: "hexpm", optional: false]}, {:db_connection, "~> 2.0", [hex: :db_connection, repo: "hexpm", optional: false]}, {:decimal, "~> 1.5", [hex: :decimal, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}], "hexpm"},
-  "telemetry": {:hex, :telemetry, "0.4.0", "8339bee3fa8b91cb84d14c2935f8ecf399ccd87301ad6da6b71c09553834b2ab", [:rebar3], [], "hexpm"},
+  "postgrex": {:hex, :postgrex, "0.16.5", "fcc4035cc90e23933c5d69a9cd686e329469446ef7abba2cf70f08e2c4b69810", [:mix], [{:connection, "~> 1.1", [hex: :connection, repo: "hexpm", optional: false]}, {:db_connection, "~> 2.1", [hex: :db_connection, repo: "hexpm", optional: false]}, {:decimal, "~> 1.5 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}, {:table, "~> 0.1.0", [hex: :table, repo: "hexpm", optional: true]}], "hexpm", "edead639dc6e882618c01d8fc891214c481ab9a3788dfe38dd5e37fd1d5fb2e8"},
+  "telemetry": {:hex, :telemetry, "1.1.0", "a589817034a27eab11144ad24d5c0f9fab1f58173274b1e9bae7074af9cbee51", [:rebar3], [], "hexpm", "b727b2a1f75614774cff2d7565b64d0dfa5bd52ba517f16543e6fc7efcc0df48"},
 }