diff --git a/packages/app/src/cli/models/extensions/specification.ts b/packages/app/src/cli/models/extensions/specification.ts
index ab5ad22008..26a5b4b9bc 100644
--- a/packages/app/src/cli/models/extensions/specification.ts
+++ b/packages/app/src/cli/models/extensions/specification.ts
@@ -55,9 +55,10 @@ export interface BuildAsset {
   static?: boolean
 }
 
-type BuildConfig =
-  | {mode: 'none'}
-  | {mode: 'ui' | 'theme' | 'function' | 'tax_calculation' | 'copy_files'; steps: ReadonlyArray<BuildStep>}
+interface BuildConfig {
+  mode: 'ui' | 'theme' | 'function' | 'tax_calculation' | 'copy_files' | 'none'
+  steps: ReadonlyArray<BuildStep>
+}
 /**
  * Extension specification with all the needed properties and methods to load an extension.
  */
@@ -204,7 +205,7 @@ export function createExtensionSpecification<TConfiguration extends BaseConfigTy
     experience: spec.experience ?? 'extension',
     uidStrategy: spec.uidStrategy ?? (spec.experience === 'configuration' ? 'single' : 'uuid'),
     getDevSessionUpdateMessages: spec.getDevSessionUpdateMessages,
-    buildConfig: spec.buildConfig ?? {mode: 'none'},
+    buildConfig: spec.buildConfig ?? {mode: 'none', steps: []},
   }
   const merged = {...defaults, ...spec}
 
@@ -265,7 +266,7 @@ export function createConfigExtensionSpecification<TConfiguration extends BaseCo
     transformRemoteToLocal: resolveReverseAppConfigTransform(spec.schema, spec.transformConfig),
     experience: 'configuration',
     uidStrategy: spec.uidStrategy ?? 'single',
-    buildConfig: spec.buildConfig ?? {mode: 'none'},
+    buildConfig: spec.buildConfig ?? {mode: 'none', steps: []},
     getDevSessionUpdateMessages: spec.getDevSessionUpdateMessages,
     patchWithAppDevURLs: spec.patchWithAppDevURLs,
     copyStaticAssets: spec.copyStaticAssets,
@@ -279,7 +280,7 @@ export function createContractBasedModuleSpecification<TConfiguration extends Ba
     identifier: spec.identifier,
     schema: zod.any({}) as unknown as ZodSchemaType<TConfiguration>,
     appModuleFeatures: spec.appModuleFeatures,
-    buildConfig: spec.buildConfig ?? {mode: 'none'},
+    buildConfig: spec.buildConfig ?? {mode: 'none', steps: []},
     deployConfig: async (config, directory) => {
       let parsedConfig = configWithoutFirstClassFields(config)
       if (spec.appModuleFeatures().includes('localization')) {
diff --git a/packages/app/src/cli/models/extensions/specifications/app_config_hosted_app_home.test.ts b/packages/app/src/cli/models/extensions/specifications/app_config_hosted_app_home.test.ts
index 9824718961..0f9ac44283 100644
--- a/packages/app/src/cli/models/extensions/specifications/app_config_hosted_app_home.test.ts
+++ b/packages/app/src/cli/models/extensions/specifications/app_config_hosted_app_home.test.ts
@@ -1,9 +1,6 @@
 import spec from './app_config_hosted_app_home.js'
 import {placeholderAppConfiguration} from '../../app/app.test-data.js'
-import {copyDirectoryContents} from '@shopify/cli-kit/node/fs'
-import {describe, expect, test, vi} from 'vitest'
-
-vi.mock('@shopify/cli-kit/node/fs')
+import {describe, expect, test} from 'vitest'
 
 describe('hosted_app_home', () => {
   describe('transform', () => {
@@ -54,43 +51,42 @@ describe('hosted_app_home', () => {
     })
   })
 
-  describe('copyStaticAssets', () => {
-    test('should copy static assets from source to output directory', async () => {
-      vi.mocked(copyDirectoryContents).mockResolvedValue(undefined)
-      const config = {static_root: 'public'}
-      const directory = '/app/root'
-      const outputPath = '/output/dist/bundle.js'
-
-      await spec.copyStaticAssets!(config, directory, outputPath)
-
-      expect(copyDirectoryContents).toHaveBeenCalledWith('/app/root/public', '/output/dist')
+  describe('buildConfig', () => {
+    test('should use copy_files mode', () => {
+      expect(spec.buildConfig.mode).toBe('copy_files')
     })
 
-    test('should not copy assets when static_root is not provided', async () => {
-      const config = {}
-      const directory = '/app/root'
-      const outputPath = '/output/dist/bundle.js'
-
-      await spec.copyStaticAssets!(config, directory, outputPath)
+    test('should have copy-static-assets step with tomlKey entry', () => {
+      if (spec.buildConfig.mode === 'none') {
+        throw new Error('Expected build_steps mode')
+      }
 
-      expect(copyDirectoryContents).not.toHaveBeenCalled()
+      expect(spec.buildConfig.steps).toHaveLength(1)
+      expect(spec.buildConfig.steps[0]).toMatchObject({
+        id: 'copy-static-assets',
+        displayName: 'Copy Static Assets',
+        type: 'copy_files',
+        config: {
+          strategy: 'files',
+          definition: {files: [{tomlKey: 'static_root'}]},
+        },
+      })
     })
 
-    test('should throw error when copy fails', async () => {
-      vi.mocked(copyDirectoryContents).mockRejectedValue(new Error('Permission denied'))
-      const config = {static_root: 'public'}
-      const directory = '/app/root'
-      const outputPath = '/output/dist/bundle.js'
+    test('config should be serializable to JSON', () => {
+      if (spec.buildConfig.mode === 'none') {
+        throw new Error('Expected build_steps mode')
+      }
 
-      await expect(spec.copyStaticAssets!(config, directory, outputPath)).rejects.toThrow(
-        'Failed to copy static assets from /app/root/public to /output/dist: Permission denied',
-      )
-    })
-  })
+      const serialized = JSON.stringify(spec.buildConfig)
+      expect(serialized).toBeDefined()
 
-  describe('buildConfig', () => {
-    test('should have hosted_app_home build mode', () => {
-      expect(spec.buildConfig).toEqual({mode: 'none'})
+      const deserialized = JSON.parse(serialized)
+      expect(deserialized.steps).toHaveLength(1)
+      expect(deserialized.steps[0].config).toEqual({
+        strategy: 'files',
+        definition: {files: [{tomlKey: 'static_root'}]},
+      })
     })
   })
 
diff --git a/packages/app/src/cli/models/extensions/specifications/app_config_hosted_app_home.ts b/packages/app/src/cli/models/extensions/specifications/app_config_hosted_app_home.ts
index b11578d83e..873d18d64b 100644
--- a/packages/app/src/cli/models/extensions/specifications/app_config_hosted_app_home.ts
+++ b/packages/app/src/cli/models/extensions/specifications/app_config_hosted_app_home.ts
@@ -1,7 +1,5 @@
 import {BaseSchemaWithoutHandle} from '../schemas.js'
 import {TransformationConfig, createConfigExtensionSpecification} from '../specification.js'
-import {copyDirectoryContents} from '@shopify/cli-kit/node/fs'
-import {dirname, joinPath} from '@shopify/cli-kit/node/path'
 import {zod} from '@shopify/cli-kit/node/schema'
 
 const HostedAppHomeSchema = BaseSchemaWithoutHandle.extend({
@@ -16,18 +14,24 @@ export const HostedAppHomeSpecIdentifier = 'hosted_app_home'
 
 const hostedAppHomeSpec = createConfigExtensionSpecification({
   identifier: HostedAppHomeSpecIdentifier,
-  buildConfig: {mode: 'none'} as const,
+  buildConfig: {
+    mode: 'copy_files',
+    steps: [
+      {
+        id: 'copy-static-assets',
+        displayName: 'Copy Static Assets',
+        type: 'copy_files',
+        config: {
+          strategy: 'files',
+          definition: {
+            files: [{tomlKey: 'static_root'}],
+          },
+        },
+      },
+    ],
+  },
   schema: HostedAppHomeSchema,
   transformConfig: HostedAppHomeTransformConfig,
-  copyStaticAssets: async (config, directory, outputPath) => {
-    if (!config.static_root) return
-    const sourceDir = joinPath(directory, config.static_root)
-    const outputDir = dirname(outputPath)
-
-    return copyDirectoryContents(sourceDir, outputDir).catch((error) => {
-      throw new Error(`Failed to copy static assets from ${sourceDir} to ${outputDir}: ${error.message}`)
-    })
-  },
 })
 
 export default hostedAppHomeSpec