Add all layers.

sportshub-application/pom.xml

@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <parent>
+        <groupId>org.sportshub</groupId>
+        <artifactId>sportshub-parent</artifactId>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath/> <!-- lookup parent from repository -->
+    </parent>
+
+    <artifactId>sportshub-application</artifactId>
+
+    <name>sportshub-application</name>
+    <description>Demo project for Spring Boot</description>
+
+    <packaging>jar</packaging>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.sportshub</groupId>
+            <artifactId>sportshub-domain</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-context</artifactId>
+        </dependency>
+    </dependencies>
+</project>

sportshub-application/src/main/java/org/sportshub/application/user/UserUseCases.java

@@ -0,0 +1,21 @@
+package org.sportshub.application.user;
+
+import java.util.Optional;
+import java.util.UUID;
+
+import org.sportshub.domain.user.model.User;
+import org.sportshub.domain.user.port.UserPort;
+import org.springframework.stereotype.Service;
+
+@Service
+public class UserUseCases {
+    private final UserPort userPort;
+
+    public UserUseCases(final UserPort userPort) {
+        this.userPort = userPort;
+    }
+
+    public Optional<User> findById(UUID userId) {
+        return userPort.findById(userId);
+    }
+}