diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..b9aedee
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,28 @@
+name: CI
+
+on:
+  pull_request:
+    branches:
+      - '**'
+  push:
+    branches:
+      - main
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '22.12.0'
+
+      - name: Install dependencies
+        run: npm install
+
+      - name: Run unit tests
+        run: npm run test -- --watch=false --browsers=ChromeHeadless
diff --git a/src/app/app-import-normalization.spec.ts b/src/app/app-import-normalization.spec.ts
new file mode 100644
index 0000000..3b5622b
--- /dev/null
+++ b/src/app/app-import-normalization.spec.ts
@@ -0,0 +1,285 @@
+import { TestBed } from '@angular/core/testing';
+import { App } from './app';
+import { AnnotationTemplatesService, AnnotationTemplate } from './annotation-templates.service';
+import { PageAnnotations } from './models/annotation.model';
+import { Language, TranslationService } from './i18n/translation.service';
+
+describe('App import normalization', () => {
+  class AnnotationTemplatesServiceStub {
+    readonly defaultTemplateId = 'stub-default-template';
+    private readonly templates: AnnotationTemplate[] = [
+      {
+        id: this.defaultTemplateId,
+        name: 'Default',
+        createdAt: 0,
+        pages: [],
+      },
+    ];
+
+    readonly storeLastCoordsSpy = jasmine.createSpy<(pages: readonly PageAnnotations[]) => void>(
+      'storeLastCoords'
+    );
+
+    getTemplates(): AnnotationTemplate[] {
+      return this.templates.map((template) => ({
+        ...template,
+        pages: template.pages.map((page) => ({
+          num: page.num,
+          fields: page.fields.map((field) => ({ ...field })),
+        })),
+      }));
+    }
+
+    saveTemplate(): AnnotationTemplate | null {
+      return null;
+    }
+
+    deleteTemplate(): void {}
+
+    storeLastCoords(pages: readonly PageAnnotations[]): void {
+      this.storeLastCoordsSpy(pages);
+    }
+
+    loadLastCoords(): PageAnnotations[] | null {
+      return null;
+    }
+
+  }
+
+  class TranslationServiceStub {
+    readonly supportedLanguages: readonly Language[] = ['es-ES'];
+
+    translate(key: string): string {
+      return key;
+    }
+
+    setLanguage(): void {}
+
+    getCurrentLanguage(): Language {
+      return this.supportedLanguages[0];
+    }
+
+    language: any;
+  }
+
+  let alertSpy: jasmine.Spy<(message?: string) => void>;
+  let consoleErrorSpy: jasmine.Spy;
+
+  beforeEach(async () => {
+    await TestBed.configureTestingModule({
+      imports: [App],
+      providers: [
+        { provide: AnnotationTemplatesService, useClass: AnnotationTemplatesServiceStub },
+        { provide: TranslationService, useClass: TranslationServiceStub },
+      ],
+    }).compileComponents();
+
+    alertSpy = spyOn(window, 'alert').and.stub();
+    consoleErrorSpy = spyOn(console, 'error').and.stub();
+  });
+
+  it('normalizes imported coordinates with inconsistent values', () => {
+    const fixture = TestBed.createComponent(App);
+    const app = fixture.componentInstance;
+
+    app.coordsTextModel = JSON.stringify(
+      {
+        pages: [
+          {
+            num: '2',
+            fields: [
+              {
+                x: '10.234',
+                y: '20.789',
+                mapField: '  customer . address [ 0 ]  ',
+                fontSize: '12.3456',
+                color: '  #FF00AA  ',
+                type: 'TEXT',
+                value: ['   Hello   ', '', null],
+              },
+              {
+                x: '30',
+                y: 'NaN',
+                mapField: '   ',
+                fontSize: '-5',
+                color: '',
+                type: 'number',
+                value: '  123.456 ',
+                decimals: '2',
+                appender: '  kg ',
+              },
+              {
+                x: '50.555',
+                y: '60.444',
+                mapField: '',
+                fontSize: '0',
+                color: 'rgba(255, 128, 0, 0.5)',
+                type: 'NUMBER',
+                value: ' 987.654 ',
+                decimals: '3.7',
+                appender: '  kg ',
+              },
+            ],
+          },
+          {
+            num: '1',
+            fields: [
+              {
+                x: '5',
+                y: '15',
+                mapField: '   ',
+                fontSize: 0,
+                color: '#abc',
+                type: 'radio',
+                value: false,
+              },
+              {
+                x: '15.999',
+                y: '25.111',
+                mapField: ['', ' order . total '],
+                fontSize: '16',
+                color: 'rgb(34, 51, 68)',
+                type: 'NUMBER',
+                value: '',
+                decimals: '2',
+                appender: '\tUSD ',
+              },
+            ],
+          },
+          {
+            num: '0',
+            fields: [
+              {
+                x: 1,
+                y: 1,
+                mapField: 'should be skipped',
+              },
+            ],
+          },
+          'not-an-object',
+          null,
+        ],
+      },
+      null,
+      2
+    );
+
+    app.applyCoordsText();
+
+    expect(alertSpy).not.toHaveBeenCalled();
+    expect(consoleErrorSpy).not.toHaveBeenCalled();
+    expect(app.coords()).toEqual([
+      {
+        num: 1,
+        fields: [
+          {
+            x: 5,
+            y: 15,
+            mapField: 'false',
+            fontSize: 14,
+            color: '#aabbcc',
+            type: 'radio',
+            value: 'false',
+          },
+          {
+            x: 16,
+            y: 25.11,
+            mapField: 'order.total',
+            fontSize: 16,
+            color: '#223344',
+            type: 'number',
+            decimals: 2,
+            appender: '\tUSD ',
+          },
+        ],
+      },
+      {
+        num: 2,
+        fields: [
+          {
+            x: 10.23,
+            y: 20.79,
+            mapField: 'customer.address[0]',
+            fontSize: 12.35,
+            color: '#ff00aa',
+            type: 'text',
+            value: 'Hello',
+          },
+          {
+            x: 50.56,
+            y: 60.44,
+            mapField: '987.654',
+            fontSize: 14,
+            color: '#ff8000',
+            type: 'number',
+            value: '987.654',
+            decimals: 4,
+            appender: '  kg ',
+          },
+        ],
+      },
+    ]);
+  });
+
+  it('keeps the current coordinates and alerts when JSON is malformed', () => {
+    const fixture = TestBed.createComponent(App);
+    const app = fixture.componentInstance;
+
+    const initialCoords: PageAnnotations[] = [
+      {
+        num: 3,
+        fields: [
+          {
+            x: 1,
+            y: 2,
+            mapField: 'field',
+            fontSize: 14,
+            color: '#000000',
+            type: 'text',
+            value: 'value',
+          },
+        ],
+      },
+    ];
+
+    app.coords.set(initialCoords);
+    app.coordsTextModel = '{"pages": [invalid]';
+
+    app.applyCoordsText();
+
+    expect(alertSpy).toHaveBeenCalledTimes(1);
+    expect(consoleErrorSpy).toHaveBeenCalled();
+    expect(app.coords()).toEqual(initialCoords);
+  });
+
+  it('keeps the current coordinates and alerts when pages collection is invalid', () => {
+    const fixture = TestBed.createComponent(App);
+    const app = fixture.componentInstance;
+
+    const initialCoords: PageAnnotations[] = [
+      {
+        num: 1,
+        fields: [
+          {
+            x: 10,
+            y: 20,
+            mapField: 'existing',
+            fontSize: 14,
+            color: '#000000',
+            type: 'text',
+            value: 'initial',
+          },
+        ],
+      },
+    ];
+
+    app.coords.set(initialCoords);
+    app.coordsTextModel = '{"pages": {"1": {"num": 1, "fields": []}}}';
+
+    app.applyCoordsText();
+
+    expect(alertSpy).toHaveBeenCalledTimes(1);
+    expect(consoleErrorSpy).toHaveBeenCalled();
+    expect(app.coords()).toEqual(initialCoords);
+  });
+});