diff --git a/springboot/api/src/main/kotlin/webapp/users/payment/payment.kt b/springboot/api/src/main/kotlin/webapp/users/payment/payment.kt
new file mode 100644
index 0000000..d5c4437
--- /dev/null
+++ b/springboot/api/src/main/kotlin/webapp/users/payment/payment.kt
@@ -0,0 +1,2 @@
+package webapp.users.payment
+
diff --git a/springboot/api/src/test/kotlin/core/UserTests.kt b/springboot/api/src/test/kotlin/core/UserTests.kt
new file mode 100755
index 0000000..8617227
--- /dev/null
+++ b/springboot/api/src/test/kotlin/core/UserTests.kt
@@ -0,0 +1,114 @@
+@file:Suppress("JUnitMalformedDeclaration")
+
+package core
+
+import com.fasterxml.jackson.databind.ObjectMapper
+import jakarta.validation.Validator
+import kotlinx.coroutines.runBlocking
+import org.junit.jupiter.api.assertDoesNotThrow
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.beans.factory.getBean
+import org.springframework.boot.test.context.SpringBootTest
+import org.springframework.context.ApplicationContext
+import org.springframework.context.annotation.ComponentScan
+import org.springframework.dao.EmptyResultDataAccessException
+import org.springframework.test.context.ActiveProfiles
+import webapp.Application
+import webapp.TestUtils.Data.user
+import webapp.TestUtils.countRoles
+import webapp.TestUtils.countUsers
+import webapp.TestUtils.defaultRoles
+import webapp.TestUtils.deleteAllUsersOnly
+import webapp.core.model.EntityModel.Members.withId
+import webapp.core.utils.AppUtils.cleanField
+import webapp.core.utils.AppUtils.toJson
+import webapp.core.utils.i
+import webapp.users.User
+import webapp.users.UserDao.Dao.findOneByEmail
+import webapp.users.UserDao.Dao.save
+import kotlin.test.*
+
+
+@SpringBootTest(
+    properties = ["spring.main.web-application-type=reactive"],
+    classes = [Application::class]
+)
+@ActiveProfiles("test")
+class UserTests {
+
+    @Autowired
+    lateinit var context: ApplicationContext
+    val mapper: ObjectMapper by lazy { context.getBean() }
+    val validator: Validator by lazy { context.getBean() }
+
+    @AfterTest
+    fun cleanUp() = runBlocking { context.deleteAllUsersOnly() }
+
+    @Test
+    fun `save default user should work in this context `() = runBlocking {
+        val count = context.countUsers()
+        (user to context).save()
+        assertEquals(expected = count + 1, context.countUsers())
+    }
+
+    @Test
+    fun `count users, expected 0`() =
+        runBlocking {
+            assertEquals(
+                0,
+                context.countUsers(),
+                "because init sql script does not inserts default users."
+            )
+        }
+
+    @Test
+    fun `count roles, expected 3`() = runBlocking {
+        context.run {
+            assertEquals(
+                defaultRoles.size,
+                countRoles(),
+                "Because init sql script does insert default roles."
+            )
+        }
+    }
+
+    @Test
+    fun `display user formatted in JSON`() = assertDoesNotThrow {
+        (user to context).toJson.let(::i)
+    }
+
+    @Test
+    fun `check toJson build a valid json format`(): Unit = assertDoesNotThrow {
+        (user to context).toJson.let(mapper::readTree)
+    }
+
+
+    @Test
+    fun `test cleanField extension function`() = assertEquals(
+        "login",
+        "`login`".cleanField(),
+        "Backtick should be removed"
+    )
+
+
+    @Test
+    fun `check findOneByEmail with non-existent email`(): Unit = runBlocking {
+        assertEquals(0, context.countUsers(), "context should not have a user recorded in database")
+        context.findOneByEmail<User>("user@dummy.com").apply {
+            assertFalse(isRight())
+            assertTrue(isLeft())
+        }.mapLeft { assertTrue(it is EmptyResultDataAccessException) }
+    }
+
+
+    @Test
+    fun `check findOneByEmail with existant email`(): Unit = runBlocking {
+        assertEquals(0, context.countUsers(), "context should not have a user recorded in database")
+        (user to context).save()
+        assertEquals(1, context.countUsers(), "context should have only one user recorded in database")
+        context.findOneByEmail<User>(user.email).apply {
+            assertTrue(isRight())
+            assertFalse(isLeft())
+        }.map { assertEquals(it, user.withId(it.id!!)) }
+    }
+}
\ No newline at end of file
diff --git a/springboot/api/src/test/kotlin/webapp/users/UserDaoTests.kt b/springboot/api/src/test/kotlin/webapp/users/UserDaoTests.kt
new file mode 100755
index 0000000..3bdd9ca
--- /dev/null
+++ b/springboot/api/src/test/kotlin/webapp/users/UserDaoTests.kt
@@ -0,0 +1,108 @@
+@file:Suppress("JUnitMalformedDeclaration")
+
+package webapp.users
+
+import com.fasterxml.jackson.databind.ObjectMapper
+import jakarta.validation.Validator
+import kotlinx.coroutines.runBlocking
+import org.junit.jupiter.api.assertDoesNotThrow
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.beans.factory.getBean
+import org.springframework.boot.test.context.SpringBootTest
+import org.springframework.context.ApplicationContext
+import org.springframework.dao.EmptyResultDataAccessException
+import org.springframework.test.context.ActiveProfiles
+import webapp.TestUtils.Data.user
+import webapp.TestUtils.countRoles
+import webapp.TestUtils.countUsers
+import webapp.TestUtils.defaultRoles
+import webapp.TestUtils.deleteAllUsersOnly
+import webapp.core.model.EntityModel.Members.withId
+import webapp.core.utils.AppUtils.cleanField
+import webapp.core.utils.AppUtils.toJson
+import webapp.core.utils.i
+import webapp.users.UserDao.Dao.findOneByEmail
+import webapp.users.UserDao.Dao.save
+import kotlin.test.*
+
+
+@SpringBootTest(properties = ["spring.main.web-application-type=reactive"])
+@ActiveProfiles("test")
+class UserDaoTests {
+
+    @Autowired
+    lateinit var context: ApplicationContext
+    val mapper: ObjectMapper by lazy { context.getBean() }
+    val validator: Validator by lazy { context.getBean() }
+
+    @AfterTest
+    fun cleanUp() = runBlocking { context.deleteAllUsersOnly() }
+
+    @Test
+    fun `save default user should work in this context `() = runBlocking {
+        val count = context.countUsers()
+        (user to context).save()
+        assertEquals(expected = count + 1, context.countUsers())
+    }
+
+    @Test
+    fun `count users, expected 0`() =
+        runBlocking {
+            assertEquals(
+                0,
+                context.countUsers(),
+                "because init sql script does not inserts default users."
+            )
+        }
+
+    @Test
+    fun `count roles, expected 3`() = runBlocking {
+        context.run {
+            assertEquals(
+                defaultRoles.size,
+                countRoles(),
+                "Because init sql script does insert default roles."
+            )
+        }
+    }
+
+    @Test
+    fun `display user formatted in JSON`() = assertDoesNotThrow {
+        (user to context).toJson.let(::i)
+    }
+
+    @Test
+    fun `check toJson build a valid json format`(): Unit = assertDoesNotThrow {
+        (user to context).toJson.let(mapper::readTree)
+    }
+
+
+    @Test
+    fun `test cleanField extension function`() = assertEquals(
+        "login",
+        "`login`".cleanField(),
+        "Backtick should be removed"
+    )
+
+
+    @Test
+    fun `check findOneByEmail with non-existent email`(): Unit = runBlocking {
+        assertEquals(0, context.countUsers(), "context should not have a user recorded in database")
+        context.findOneByEmail<User>("user@dummy.com").apply {
+            assertFalse(isRight())
+            assertTrue(isLeft())
+        }.mapLeft { assertTrue(it is EmptyResultDataAccessException) }
+    }
+
+
+    @Test
+    fun `check findOneByEmail with existant email`(): Unit = runBlocking {
+        assertEquals(0, context.countUsers(), "context should not have a user recorded in database")
+        (user to context).save()
+        assertEquals(1, context.countUsers(), "context should have only one user recorded in database")
+        context.findOneByEmail<User>(user.email).apply {
+            assertTrue(isRight())
+            assertFalse(isLeft())
+        }.map { assertEquals(it, user.withId(it.id!!)) }
+    }
+}
\ No newline at end of file