diff --git a/lib/geef.ex b/lib/geef.ex
new file mode 100644
index 0000000..f2501e0
--- /dev/null
+++ b/lib/geef.ex
@@ -0,0 +1,15 @@
+defmodule Geef do
+
+  defmacro __using__(_) do
+    quote do
+      alias Geef.Repository
+      alias Geef.Reference
+      alias Geef.Object
+      alias Geef.Commit
+      alias Geef.Tree
+      alias Geef.Blob
+      alias Geef.Tag
+    end
+  end
+
+end
diff --git a/lib/geef/blob.ex b/lib/geef/blob.ex
new file mode 100644
index 0000000..beb73dd
--- /dev/null
+++ b/lib/geef/blob.ex
@@ -0,0 +1,21 @@
+defmodule Geef.Blob do
+  alias Geef.Object
+
+  def lookup(repo, id) do
+    case :geef_obj.lookup(repo, id) do
+      {:ok, obj} ->
+        {:ok, Object.new obj}
+      error ->
+        error
+    end
+  end
+
+  def size(obj = Object[type: :blob]) do
+    :geef_blob.size(set_elem(obj, 0, :geef_object))
+  end
+
+  def content(obj = Object[type: :blob]) do
+    :geef_blob.content(set_elem(obj, 0, :geef_object))
+  end
+
+end
diff --git a/lib/geef/commit.ex b/lib/geef/commit.ex
new file mode 100644
index 0000000..de3f005
--- /dev/null
+++ b/lib/geef/commit.ex
@@ -0,0 +1,17 @@
+defmodule Geef.Commit do
+  alias Geef.Object
+
+  def lookup(repo, id) do
+    case :geef_commit.lookup(repo, id) do
+      {:ok, commit} ->
+        {:ok, Object.new commit}
+      error ->
+        error
+    end
+  end
+
+  def tree_id(commit = Object[type: :commit]) do
+    :geef_commit.tree_id(set_elem(commit, 0, :geef_object))
+  end
+
+end
diff --git a/lib/geef/odb.ex b/lib/geef/odb.ex
index 264ee7a..79f63d0 100644
--- a/lib/geef/odb.ex
+++ b/lib/geef/odb.ex
@@ -3,5 +3,7 @@ defmodule Geef.Odb do
     :geef_odb.exists(pid, id)
   end
 
+  def write(pid, content, type), do: :geef_odb.write(pid, content, type)
+
   def stop(pid), do: :geef_odb.stop(pid)
 end
diff --git a/lib/geef/tree.ex b/lib/geef/tree.ex
new file mode 100644
index 0000000..f26ce87
--- /dev/null
+++ b/lib/geef/tree.ex
@@ -0,0 +1,17 @@
+defmodule Geef.Tree do
+  alias Geef.Object
+
+  def lookup(repo, id) do
+    case :geef_tree.lookup(repo, id) do
+      {:ok, obj} ->
+        {:ok, Object.new obj}
+      error ->
+        error
+    end
+  end
+
+  def get(tree = Object[type: :tree], path) do
+    :geef_tree.get(set_elem(tree, 0, :geef_object), path)
+  end
+
+end
diff --git a/src/geef_blob.erl b/src/geef_blob.erl
index b0c7798..16a4af4 100644
--- a/src/geef_blob.erl
+++ b/src/geef_blob.erl
@@ -6,16 +6,12 @@
 
 -include("geef_records.hrl").
 
--export([lookup/2, id/1, size/1, content/1]).
+-export([lookup/2, size/1, content/1]).
 
 -spec lookup(pid(), geef_oid() | iolist()) -> geef_object().
 lookup(Repo, Id) ->
     geef_obj:lookup(Repo, Id, blob).
 
--spec id(geef_object()) -> geef_oid().
-id(Obj = #geef_object{type=blob}) ->
-    geef_obj:id(Obj).
-
 size(#geef_object{type=blob, handle=Handle}) ->
     geef_nif:blob_size(Handle).
 
diff --git a/src/geef_commit.erl b/src/geef_commit.erl
index db97c49..be6a69b 100644
--- a/src/geef_commit.erl
+++ b/src/geef_commit.erl
@@ -1,5 +1,5 @@
 -module(geef_commit).
--export([tree_id/1, tree/1, id/1, lookup/2]).
+-export([tree_id/1, tree/1, lookup/2]).
 
 -include("geef_records.hrl").
 
@@ -18,7 +18,4 @@ tree(#geef_object{type=commit,handle=Handle}) ->
 
 -spec lookup(pid(), geef_oid() | iolist()) -> geef_object().
 lookup(Repo, Id) ->
-    geef_object:lookup(Repo, Id, commit).
-
-id(Obj = #geef_object{type=commit}) ->
-    geef_object:id(Obj).
+    geef_obj:lookup(Repo, Id, commit).
diff --git a/src/geef_tree.erl b/src/geef_tree.erl
index 32e72fc..7da9bb4 100644
--- a/src/geef_tree.erl
+++ b/src/geef_tree.erl
@@ -4,7 +4,7 @@
 -include_lib("eunit/include/eunit.hrl").
 -endif.
 
--export([get/2, id/1, lookup/2]).
+-export([get/2, lookup/2]).
 
 -include("geef_records.hrl").
 
@@ -17,10 +17,6 @@ get(#geef_object{type=tree,handle=Handle}, Path) ->
 	    Other
     end.
 
--spec id(geef_object()) -> {ok, geef_oid()} | {error, term()}.
-id(Obj = #geef_object{type=tree}) ->
-    geef_object:id(Obj).
-
 -spec lookup(pid(), geef_oid() | iolist()) -> {ok, geef_object()} | {error, term()}.
 lookup(Repo, Id) ->
     geef_obj:lookup(Repo, Id, tree).