diff --git a/resources/functions/user/check_user.sql b/resources/functions/user/check_user.sql
new file mode 100644
index 0000000..4142278
--- /dev/null
+++ b/resources/functions/user/check_user.sql
@@ -0,0 +1,18 @@
+create or replace function check_user(in username text, in plain_password text, out resource json) language plpgsql as
+$$
+declare
+    _username alias for username;
+begin
+    select
+       case when count(u) = 1
+       then to_json(json_populate_record(null::user_lite, to_json(u)))  -- TODO refactor this !
+       else null end
+    into resource
+    from "user" as u
+    where u.username = lower(_username)
+      and u.password = crypt(plain_password, u.password)
+    group by u;
+end;
+$$;
+
+-- drop function if exists check_user(text, text, out json);
\ No newline at end of file
diff --git a/resources/functions/user/find_user_by_id.sql b/resources/functions/user/find_user_by_id.sql
new file mode 100644
index 0000000..7f2e1ca
--- /dev/null
+++ b/resources/functions/user/find_user_by_id.sql
@@ -0,0 +1,12 @@
+create or replace procedure find_user_by_id(in id uuid, inout resource json) language plpgsql as
+$$
+declare
+    _id alias for id;
+begin
+    select to_json(u) into resource
+    from "user" as u
+    where u.id = _id;
+end;
+$$;
+
+-- drop procedure if exists find_user_by_id(inout json);
\ No newline at end of file
diff --git a/resources/functions/user/find_user_by_username.sql b/resources/functions/user/find_user_by_username.sql
new file mode 100644
index 0000000..c8c6e4b
--- /dev/null
+++ b/resources/functions/user/find_user_by_username.sql
@@ -0,0 +1,12 @@
+create or replace procedure find_user_by_username(in username text, inout resource json) language plpgsql as
+$$
+declare
+    _username alias for username;
+begin
+    select to_json(u) into resource
+    from "user" as u
+    where u.username = _username;
+end;
+$$;
+
+-- drop procedure if exists find_user_by_username(text, inout json);
\ No newline at end of file
diff --git a/resources/functions/user/insert_user.sql b/resources/functions/user/insert_user.sql
new file mode 100644
index 0000000..803b268
--- /dev/null
+++ b/resources/functions/user/insert_user.sql
@@ -0,0 +1,20 @@
+create or replace procedure insert_user(inout resource json) language plpgsql as
+$$
+declare
+    new_id uuid;
+begin
+    insert into "user" (username, password, blocked_at)
+    select
+        username,
+        crypt(resource->>'plain_password', gen_salt('bf', 8)),
+        case when blocked_at is not null then now() else null end
+    from json_populate_record(null::"user", resource)
+    returning id into new_id;
+
+    select to_json(u) into resource
+    from "user" as u
+    where u.id = new_id;
+end;
+$$;
+
+-- drop procedure if exists insert_user(inout json);
\ No newline at end of file
diff --git a/resources/sql/migrations/0000-init_schema.up.sql b/resources/sql/migrations/0000-init_schema.up.sql
index 8ec5264..4f6577b 100644
--- a/resources/sql/migrations/0000-init_schema.up.sql
+++ b/resources/sql/migrations/0000-init_schema.up.sql
@@ -1,9 +1,5 @@
 -- Users
 create extension if not exists pgcrypto;
--- select *
--- from "user"
--- where username = lower('nick@example.com')
---   and password = crypt('12346', password);
 
 create table "user"
 (
diff --git a/resources/sql/migrations/0000-init_view.down.sql b/resources/sql/migrations/0000-init_view.down.sql
new file mode 100644
index 0000000..3a46f2f
--- /dev/null
+++ b/resources/sql/migrations/0000-init_view.down.sql
@@ -0,0 +1,2 @@
+-- User
+drop view if exists user_lite;
\ No newline at end of file
diff --git a/resources/sql/migrations/0000-init_view.up.sql b/resources/sql/migrations/0000-init_view.up.sql
new file mode 100644
index 0000000..354be37
--- /dev/null
+++ b/resources/sql/migrations/0000-init_view.up.sql
@@ -0,0 +1,5 @@
+-- User
+create or replace view user_lite as
+select u.id, u.created_at, u.blocked_at, u.username
+from "user" u
+where u.blocked_at is null;
\ No newline at end of file
diff --git a/resources/tests/user.sql b/resources/tests/user.sql
new file mode 100644
index 0000000..6db54af
--- /dev/null
+++ b/resources/tests/user.sql
@@ -0,0 +1,31 @@
+do
+$$
+declare
+    created_user json := '{"username": "george", "plain_password": "azerty"}';
+    selected_user json;
+    exist_user json;
+begin
+    call insert_user(created_user);
+    assert created_user->>'username' = 'george', 'username must be george';
+    assert created_user->>'password' is not null, 'password must be generated';
+
+    call find_user_by_id((created_user->>'id')::uuid, selected_user);
+    assert selected_user->>'username' = 'george', 'username must be george';
+
+    call find_user_by_username(created_user->>'username', selected_user);
+    assert selected_user->>'username' = 'george', 'username must be george';
+
+    select check_user('george', 'azerty') into exist_user;
+    assert exist_user is not null, format('the function check_user must be return user object if username and password is correct, %s is return', exist_user::text);
+    assert exist_user->>'username' = 'george', format('the function check_user must be return user object with username is "george", %s is return', exist_user::text);
+    assert exist_user->>'password' is null, format('the function check_user must not be return the password, %s is return', exist_user::text);
+
+    delete from "user" where username = 'george';
+
+    select check_user('george', 'azerty') into exist_user;
+    assert exist_user is null, format('the function check_user must be return null if user not exist, %s is return', exist_user::text);
+
+    raise notice 'user test pass';
+end;
+$$;
+