diff --git a/src/scripts/repositories.js b/src/scripts/repositories.js
new file mode 100644
index 0000000..caf9d1d
--- /dev/null
+++ b/src/scripts/repositories.js
@@ -0,0 +1,27 @@
+const getRepositoryName = (split, max) => {
+  let repositoryName = '';
+  for (let i = 0; i < max; i++) {
+    repositoryName += `${split[i]}/`;
+  }
+  return repositoryName;
+};
+
+export const getBranching =
+  (min = 1, max = 1) =>
+  (repositories) =>
+    repositories.sort().reduce(function (acc, image) {
+      const split = image.split('/');
+      if (split.length > min && min > 0) {
+        const repoName = getRepositoryName(split, max);
+        if (acc.length === 0 || acc[acc.length - 1].repo != repoName) {
+          acc.push({
+            repo: repoName,
+            images: [],
+          });
+        }
+        acc[acc.length - 1].images.push(image);
+        return acc;
+      }
+      acc.push(image);
+      return acc;
+    }, []);
diff --git a/test/repositories.test.js b/test/repositories.test.js
new file mode 100644
index 0000000..d8bc125
--- /dev/null
+++ b/test/repositories.test.js
@@ -0,0 +1,31 @@
+import { getBranching } from '../src/scripts/repositories.js';
+import assert from 'assert';
+
+describe('repositories', () => {
+  describe('getBranching', () => {
+    it('should not branch for no levels', () => {
+      const branching = getBranching(0, 0);
+      assert.deepEqual(branching(['alpine', 'debian', 'nginx']), ['alpine', 'debian', 'nginx']);
+      assert.deepEqual(branching(['alpine', 'joxit/docker-registry-ui', 'nginx']), [
+        'alpine',
+        'joxit/docker-registry-ui',
+        'nginx',
+      ]);
+    });
+
+    it('should branch for one level', () => {
+      const branching = getBranching(1, 1);
+      assert.deepEqual(branching(['alpine', 'debian', 'nginx']), ['alpine', 'debian', 'nginx']);
+      assert.deepEqual(branching(['alpine', 'joxit/docker-registry-ui', 'nginx']), [
+        'alpine',
+        { images: ['joxit/docker-registry-ui'], repo: 'joxit/' },
+        'nginx',
+      ]);
+      assert.deepEqual(branching(['alpine', 'joxit/docker-registry-ui', 'joxit/kokai', 'nginx']), [
+        'alpine',
+        { images: ['joxit/docker-registry-ui', 'joxit/kokai'], repo: 'joxit/' },
+        'nginx',
+      ]);
+    });
+  });
+});