diff --git a/.gitignore b/.gitignore
index 6890eea..713629c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,3 +5,5 @@
 rebar
 ebin/
 .eunit
+.rebar/
+_build/
\ No newline at end of file
diff --git a/c_src/commit.c b/c_src/commit.c
index b1a24d7..c3e72f1 100644
--- a/c_src/commit.c
+++ b/c_src/commit.c
@@ -30,7 +30,7 @@ geef_commit_tree(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[])
 {
 	ErlNifBinary bin;
 	geef_object *obj, *tree;
-	ERL_NIF_TERM term_obj;
+	ERL_NIF_TERM term_tree;
 
 	if (!enif_get_resource(env, argv[0], geef_object_type, (void **) &obj))
 		return enif_make_badarg(env);
@@ -40,13 +40,16 @@ geef_commit_tree(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[])
 	if (git_commit_tree((git_tree **) &tree->obj, (git_commit *) obj->obj) < 0)
 		return geef_error(env);
 
-	term_obj = enif_make_resource(env, obj);
-	enif_release_resource(obj);
+	term_tree = enif_make_resource(env, tree);
+	enif_release_resource(tree);
 
 	if (geef_oid_bin(&bin, git_object_id(tree->obj)) < 0)
 		return geef_oom(env);
 
-	return enif_make_tuple3(env, atoms.ok, enif_make_binary(env, &bin), term_obj);
+	tree->repo = obj->repo;
+	enif_keep_resource(tree->repo);
+
+	return enif_make_tuple3(env, atoms.ok, enif_make_binary(env, &bin), term_tree);
 }
 
 ERL_NIF_TERM
diff --git a/c_src/geef.c b/c_src/geef.c
index b854e1f..e0b60ff 100644
--- a/c_src/geef.c
+++ b/c_src/geef.c
@@ -31,7 +31,7 @@ geef_atoms atoms;
 
 static int load(ErlNifEnv *env, void **priv, ERL_NIF_TERM load_info)
 {
-	git_threads_init();
+	git_libgit2_init();
 
 	geef_repository_type = enif_open_resource_type(env, NULL,
 						     "repository_type", geef_repository_free, ERL_NIF_RT_CREATE, NULL);
@@ -99,7 +99,7 @@ int upgrade(ErlNifEnv* env, void** priv_data, void** old_priv_data, ERL_NIF_TERM
 
 static void unload(ErlNifEnv* env, void* priv_data)
 {
-	git_threads_shutdown();
+	git_libgit2_shutdown();
 }
 
 ERL_NIF_TERM
diff --git a/test/repo_test.erl b/test/repo_test.erl
index 5069118..581f47d 100644
--- a/test/repo_test.erl
+++ b/test/repo_test.erl
@@ -7,7 +7,8 @@ repo_test_() ->
     {foreach, fun start/0, fun stop/1, [fun bare_test/1, fun odb_write_test/1,
 					fun ref_test/1, fun index_add_test/1,
 					fun ref_iter_test/1, fun revparse_test/1,
-					fun commit_create_test/1, fun commit_message_test/1]}.
+					fun commit_create_test/1, fun commit_message_test/1,
+					fun commit_tree_test/1]}.
 
 start() ->
     {A, B, C} = now(),
@@ -111,6 +112,13 @@ commit_message_test(Repo) ->
     Resp = geef_commit:message(Commit),
     [?_assertMatch({ok, <<"Commit message">>}, Resp)].
 
+commit_tree_test(Repo) ->
+    commit_create_test(Repo),
+    CommitId = geef_oid:parse("bf968373f95f8fed2a24f9d25ebf06521359c6bc"),
+    {ok, Commit} = geef_commit:lookup(Repo, CommitId),
+    Resp = geef_commit:tree(Commit),
+    [?_assertMatch({ok, _}, Resp)].
+
 rm_r(Path) ->
     case filelib:is_dir(Path) of
 	false ->