Add all layers.

sportshub-infrastructure/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-infrastructure</artifactId>
+
+    <name>sportshub-infrastructure</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-infrastructure/src/main/java/org/sportshub/infrastructure/user/adapter/UserInMemoryAdapter.java

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+package org.sportshub.infrastructure.user.adapter;
+
+import java.util.List;
+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.Component;
+
+@Component
+public class UserInMemoryAdapter implements UserPort {
+    private static final List<User> users = List.of(
+        new User(UUID.fromString("c1a0805f-c618-47dc-bae7-bee70503644e"), "password"),
+        new User(UUID.fromString("4eff194d-dd8e-463e-974f-034bfd509f84"), "password"),
+        new User(UUID.fromString("c78d7d7c-0386-415d-86dc-98a470591e07"), "password")
+    );
+
+    @Override
+    public Optional<User> findById(final UUID userId) {
+        return users.stream()
+            .filter(user -> userId.equals(user.id()))
+            .findFirst();
+    }
+}