diff --git a/__tests__/unit/shortener.spec.ts b/__tests__/unit/shortener.spec.ts
new file mode 100644
index 0000000..0cc1b77
--- /dev/null
+++ b/__tests__/unit/shortener.spec.ts
@@ -0,0 +1,53 @@
+import Shortener from '../../lib/shortener';
+
+jest.mock('../../db', () => {
+  return {
+    __esModule: true,
+    default: {
+      get: jest
+        .fn()
+        .mockResolvedValueOnce('https://rsgarxia.is-a.dev')
+        .mockResolvedValueOnce({
+          status: 'error',
+          reason: 'URL not found',
+        }),
+      set: jest.fn().mockResolvedValueOnce(true),
+    },
+  };
+});
+
+describe('Shortener', () => {
+  describe('urlByHash method', () => {
+    describe('if Hash exists', () => {
+      it('returns URL', async () => {
+        const url = await Shortener.urlByHash('some-uuid');
+
+        expect(url).toBe('https://rsgarxia.is-a.dev');
+      });
+    });
+
+    describe('if Hash does not exist', () => {
+      it('returns JSON with error message', async () => {
+        const result = await Shortener.urlByHash('some-uuid');
+
+        expect(result).toMatchObject({
+          reason: expect.any(String),
+          status: expect.any(String),
+        });
+      });
+    });
+  });
+
+  describe('hashUrl method', () => {
+    it('returns JSON with URL hash', async () => {
+      const url = 'https://rsgarxia.is-a.dev';
+      const hash = await Shortener.hashUrl(url);
+
+      expect(hash).toMatchObject({
+        status: 'success',
+        original_url: url,
+        shortened_url: expect.any(String),
+      });
+    });
+  });
+});
diff --git a/jest.config.js b/jest.config.js
index b413e10..b9db607 100644
--- a/jest.config.js
+++ b/jest.config.js
@@ -1,5 +1,7 @@
 /** @type {import('ts-jest').JestConfigWithTsJest} */
 module.exports = {
+  verbose: true,
   preset: 'ts-jest',
   testEnvironment: 'node',
-};
\ No newline at end of file
+  testPathIgnorePatterns: ['dist/*', 'node_modules'],
+};
diff --git a/lib/shortener.ts b/lib/shortener.ts
new file mode 100644
index 0000000..75598bf
--- /dev/null
+++ b/lib/shortener.ts
@@ -0,0 +1,29 @@
+import client from '../db';
+import mmh3 from 'murmurhash3';
+
+const DOMAIN = process.env.DOMAIN || 'https://frodo.sigfried.xyz';
+
+class Shortener {
+  static async urlByHash(hash: string) {
+    const url = await client.get(hash);
+
+    return url ? url : { status: 'error', reason: 'URL not found' };
+  }
+
+  static async hashUrl(url: string) {
+    const hash = mmh3.murmur32HexSync(url);
+
+    const maybeKeyValue = await this.urlByHash(hash);
+    if (!maybeKeyValue) {
+      await client.set(hash, url);
+    }
+
+    return {
+      status: 'success',
+      original_url: url,
+      shortened_url: `${DOMAIN}/${hash}`,
+    };
+  }
+}
+
+export default Shortener;