diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..270625d
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,116 @@
+name: CI
+
+on:
+  push:
+    branches: [ "main" ]
+  pull_request:
+    branches: [ "main", "dev" ]
+
+permissions:
+  contents: read
+
+jobs:
+
+  # ---------------------------------------------------------------------
+  # 1. Build + test on every push and every PR
+  # ---------------------------------------------------------------------
+  test:
+    name: Build & Test
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v7
+
+      - name: Set up JDK 17
+        uses: actions/setup-java@v5
+        with:
+          distribution: temurin
+          java-version: '17'
+          cache: maven
+
+      - name: Make mvnw executable
+        run: chmod +x ./mvnw
+
+      - name: Run tests
+        # Tests run against the in-memory H2 DB and spring.cache.type=simple,
+        # so no Postgres/Redis service containers are needed here.
+        # WEATHER_API_KEY just needs to be non-empty; tests mock the HTTP client.
+        env:
+          WEATHER_API_KEY: dummy-ci-key
+        run: ./mvnw -B test
+
+      - name: Publish test report
+        if: always()
+        uses: dorny/test-reporter@v3
+        with:
+          name: Maven Tests
+          path: target/surefire-reports/*.xml
+          reporter: java-junit
+
+      - name: Upload JaCoCo coverage report
+        if: always()
+        uses: actions/upload-artifact@v7
+        with:
+          name: jacoco-report
+          path: target/site/jacoco/
+
+      - name: Build jar
+        env:
+          WEATHER_API_KEY: dummy-ci-key
+        run: ./mvnw -B package -DskipTests
+
+      - name: Upload jar artifact
+        uses: actions/upload-artifact@v7
+        with:
+          name: app-jar
+          path: target/*.jar
+
+  # ---------------------------------------------------------------------
+  # 2. Build + push a versioned image to Docker Hub
+  #    - runs ONLY on: pushes to main
+  #    - every push to main -> :<pom-version>  :latest
+  #    - pushes to dev, and all PRs -> this job does not run at all
+  #      (dev/PRs are still covered by the `test` job above)
+  # ---------------------------------------------------------------------
+  docker:
+    name: Build & Push Docker Image
+    needs: test
+    if: github.ref == 'refs/heads/main'
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v7
+
+      - name: Read version from pom.xml
+        id: pom
+        run: |
+          chmod +x ./mvnw
+          VERSION=$(./mvnw -q -B help:evaluate -Dexpression=project.version -DforceStdout)
+          echo "version=$VERSION" >> "$GITHUB_OUTPUT"
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Log in to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+      - name: Extract metadata (tags)
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ${{ secrets.DOCKERHUB_USERNAME }}/weatherviewer
+          tags: |
+            type=raw,value=${{ steps.pom.outputs.version }}
+            type=raw,value=latest
+
+      - name: Build and push
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
\ No newline at end of file
diff --git a/src/main/java/com/weatherviewer/mapper/LocationMapper.java b/src/main/java/com/weatherviewer/mapper/LocationMapper.java
index 4a66169..68e2d65 100644
--- a/src/main/java/com/weatherviewer/mapper/LocationMapper.java
+++ b/src/main/java/com/weatherviewer/mapper/LocationMapper.java
@@ -35,9 +35,16 @@ public abstract class LocationMapper {
      */
     @Mapping(target = "user", expression = "java(userRepository.getReferenceById(addLocationDto.getUserId()))")
     @Mapping(target = "favorite", expression = "java(addLocationDto.getFavorite() != null ? addLocationDto.getFavorite() : false)")
+    @Mapping(target = "id", ignore = true)
+    @Mapping(target = "createdAt", ignore = true)
     public abstract Location fromDto(AddLocationDto addLocationDto);
 
-    /** Builds a {@link Location} from its full DTO representation (e.g. for updates). */
+    /**
+     * Builds a {@link Location} from its full DTO representation (e.g. for updates).
+     * The owning {@code user} is intentionally left unset here — callers that need
+     * a persisted, owned entity set it separately after this conversion.
+     */
+    @Mapping(target = "user", ignore = true)
     public abstract Location fromDto(LocationDto locationDto);
 
     /**
diff --git a/src/main/java/com/weatherviewer/mapper/UserMapper.java b/src/main/java/com/weatherviewer/mapper/UserMapper.java
index d4a3e23..caf54e5 100644
--- a/src/main/java/com/weatherviewer/mapper/UserMapper.java
+++ b/src/main/java/com/weatherviewer/mapper/UserMapper.java
@@ -22,6 +22,10 @@ public interface UserMapper {
      */
     @Mapping(target = "status", expression = "java(com.weatherviewer.model.enums.UserStatus.ACTIVE)")
     @Mapping(target = "role", expression = "java(com.weatherviewer.model.enums.Role.USER)")
+    @Mapping(target = "id", ignore = true)
+    @Mapping(target = "createdAt", ignore = true)
+    @Mapping(target = "units", ignore = true)
+    @Mapping(target = "locations", ignore = true)
     User fromRecord(CreateUserDto createUserDto);
 
     /**