diff --git a/packages/cli-kit/src/public/node/themes/factories.test.ts b/packages/cli-kit/src/public/node/themes/factories.test.ts
new file mode 100644
index 00000000000..ade9266edeb
--- /dev/null
+++ b/packages/cli-kit/src/public/node/themes/factories.test.ts
@@ -0,0 +1,110 @@
+import {buildTheme, buildChecksum, buildThemeAsset} from './factories.js'
+import {describe, test, expect} from 'vitest'
+
+describe('buildTheme', () => {
+  test('returns undefined when themeJson is undefined', () => {
+    expect(buildTheme()).toBeUndefined()
+  })
+
+  test('transforms main role to live role', () => {
+    const theme = buildTheme({
+      id: 1,
+      name: 'Main Theme',
+      role: 'main',
+    })
+
+    expect(theme).toEqual({
+      id: 1,
+      name: 'Main Theme',
+      role: 'live',
+      processing: false,
+      createdAtRuntime: false,
+    })
+  })
+
+  test('preserves non-main roles and custom flags', () => {
+    const theme = buildTheme({
+      id: 2,
+      name: 'Dev Theme',
+      role: 'development',
+      processing: true,
+      createdAtRuntime: true,
+    })
+
+    expect(theme).toEqual({
+      id: 2,
+      name: 'Dev Theme',
+      role: 'development',
+      processing: true,
+      createdAtRuntime: true,
+    })
+  })
+})
+
+describe('buildChecksum', () => {
+  test('returns undefined when asset is undefined', () => {
+    expect(buildChecksum()).toBeUndefined()
+  })
+
+  test('extracts key and checksum from asset', () => {
+    const checksum = buildChecksum({
+      key: 'assets/app.js',
+      checksum: '12345',
+      attachment: undefined,
+      value: 'console.log("hello")',
+    })
+
+    expect(checksum).toEqual({
+      key: 'assets/app.js',
+      checksum: '12345',
+    })
+  })
+})
+
+describe('buildThemeAsset', () => {
+  test('returns undefined when asset is undefined', () => {
+    expect(buildThemeAsset(undefined)).toBeUndefined()
+  })
+
+  test('calculates size stats from string value', () => {
+    const value = 'body { color: red; }'
+    const asset = buildThemeAsset({
+      key: 'assets/style.css',
+      checksum: 'abc',
+      attachment: undefined,
+      value,
+    })
+
+    expect(asset).toEqual({
+      key: 'assets/style.css',
+      checksum: 'abc',
+      attachment: undefined,
+      value,
+      stats: {
+        size: value.length,
+        mtime: expect.any(Number),
+      },
+    })
+  })
+
+  test('calculates size stats from attachment when value is empty', () => {
+    const attachment = 'base64string=='
+    const asset = buildThemeAsset({
+      key: 'assets/logo.png',
+      checksum: 'def',
+      attachment,
+      value: '',
+    })
+
+    expect(asset).toEqual({
+      key: 'assets/logo.png',
+      checksum: 'def',
+      attachment,
+      value: '',
+      stats: {
+        size: attachment.length,
+        mtime: expect.any(Number),
+      },
+    })
+  })
+})