diff --git a/src/spellcheck/tests/_quick_features.test.ts b/src/spellcheck/tests/_quick_features.test.ts
new file mode 100644
index 0000000..fda07cc
--- /dev/null
+++ b/src/spellcheck/tests/_quick_features.test.ts
@@ -0,0 +1,56 @@
+import { describe, test, expect, beforeEach } from 'vitest';
+import {
+  CapitalizationFeature,
+  CapitalizationFeatureFactory,
+  GrammarPatternFeature,
+  GrammarPatternFeatureFactory,
+  FeatureManager
+} from '../features';
+
+describe('CapitalizationFeature', () => {
+  let feature: CapitalizationFeature;
+
+  beforeEach(() => {
+    feature = CapitalizationFeatureFactory.createDefault();
+  });
+
+  test('should detect sentence capitalization errors', async () => {
+    const text = 'this is a sentence. another sentence here.';
+    const results = await feature.checkText(text);
+    expect(results).toHaveLength(2);
+  });
+});
+
+describe('GrammarPatternFeature', () => {
+  let feature: GrammarPatternFeature;
+
+  beforeEach(() => {
+    feature = GrammarPatternFeatureFactory.createDefault();
+  });
+
+  test('should detect a/an errors', async () => {
+    const text = 'I have a apple and an banana.';
+    const results = await feature.checkText(text);
+    const appleError = results.find(r => r.originalText === 'a apple');
+    expect(appleError).toBeDefined();
+  });
+});
+
+describe('FeatureManager Integration', () => {
+  let manager: FeatureManager;
+
+  beforeEach(() => {
+    manager = new FeatureManager();
+  });
+
+  test('should manage multiple features', async () => {
+    const capitalization = CapitalizationFeatureFactory.createDefault();
+    const grammar = GrammarPatternFeatureFactory.createDefault();
+    manager.addFeature(capitalization);
+    manager.addFeature(grammar);
+    await manager.initializeAll();
+    const text = 'this is wrong. I have a apple.';
+    const results = await manager.checkText(text);
+    expect(results.length).toBeGreaterThan(1);
+  });
+});