diff --git a/blocksuite/affine/all/src/__tests__/utils/get-provider.ts b/blocksuite/affine/all/src/__tests__/utils/get-provider.ts
index 6a2f7deabb..00257f7f28 100644
--- a/blocksuite/affine/all/src/__tests__/utils/get-provider.ts
+++ b/blocksuite/affine/all/src/__tests__/utils/get-provider.ts
@@ -1,14 +1,7 @@
 import { Container } from '@blocksuite/global/di';
 
-import {
-  registerBlockSpecs,
-  registerStoreSpecs,
-} from '../../extensions/register';
 import { testStoreExtensions } from './store';
 
-registerStoreSpecs();
-registerBlockSpecs();
-
 export function getProvider() {
   const container = new Container();
   const exts = testStoreExtensions;
diff --git a/blocksuite/affine/all/src/effects.ts b/blocksuite/affine/all/src/effects.ts
index 1b25997c31..5c0a6d2603 100644
--- a/blocksuite/affine/all/src/effects.ts
+++ b/blocksuite/affine/all/src/effects.ts
@@ -63,8 +63,6 @@ import { effects as widgetToolbarEffects } from '@blocksuite/affine-widget-toolb
 import { effects as dataViewEffects } from '@blocksuite/data-view/effects';
 import { effects as stdEffects } from '@blocksuite/std/effects';
 
-import { registerBlockSpecs } from './extensions';
-
 export declare const _GLOBAL_:
   | typeof stdEffects
   | typeof dataViewEffects
@@ -113,7 +111,6 @@ export declare const _GLOBAL_:
   | typeof fragmentOutlineEffects;
 
 export function effects() {
-  registerBlockSpecs();
   stdEffects();
 
   dataViewEffects();
diff --git a/blocksuite/affine/all/src/extensions/index.ts b/blocksuite/affine/all/src/extensions/index.ts
index a53d7a0a9b..6a51891a73 100644
--- a/blocksuite/affine/all/src/extensions/index.ts
+++ b/blocksuite/affine/all/src/extensions/index.ts
@@ -2,4 +2,3 @@ export * from './common';
 export * from './editor-specs';
 export * from './legacy-store';
 export * from './preview-specs';
-export * from './register';
diff --git a/blocksuite/affine/all/src/extensions/register.ts b/blocksuite/affine/all/src/extensions/register.ts
deleted file mode 100644
index bcb2336c46..0000000000
--- a/blocksuite/affine/all/src/extensions/register.ts
+++ /dev/null
@@ -1,22 +0,0 @@
-import { SpecProvider } from '@blocksuite/affine-shared/utils';
-
-import {
-  EdgelessEditorBlockSpecs,
-  PageEditorBlockSpecs,
-} from './editor-specs.js';
-import { StoreExtensions } from './legacy-store.js';
-import {
-  PreviewEdgelessEditorBlockSpecs,
-  PreviewPageEditorBlockSpecs,
-} from './preview-specs.js';
-
-export function registerStoreSpecs() {
-  SpecProvider._.addSpec('store', StoreExtensions);
-}
-
-export function registerBlockSpecs() {
-  SpecProvider._.addSpec('page', PageEditorBlockSpecs);
-  SpecProvider._.addSpec('edgeless', EdgelessEditorBlockSpecs);
-  SpecProvider._.addSpec('preview:page', PreviewPageEditorBlockSpecs);
-  SpecProvider._.addSpec('preview:edgeless', PreviewEdgelessEditorBlockSpecs);
-}
diff --git a/blocksuite/affine/shared/src/utils/index.ts b/blocksuite/affine/shared/src/utils/index.ts
index f09d95f8e3..0339924963 100644
--- a/blocksuite/affine/shared/src/utils/index.ts
+++ b/blocksuite/affine/shared/src/utils/index.ts
@@ -20,7 +20,6 @@ export * from './print-to-pdf';
 export * from './reference';
 export * from './reordering';
 export * from './signal';
-export * from './spec';
 export * from './string';
 export * from './title';
 export * from './url';
diff --git a/blocksuite/affine/shared/src/utils/spec/index.ts b/blocksuite/affine/shared/src/utils/spec/index.ts
deleted file mode 100644
index 38bfcb6f95..0000000000
--- a/blocksuite/affine/shared/src/utils/spec/index.ts
+++ /dev/null
@@ -1,2 +0,0 @@
-export * from './spec-builder.js';
-export * from './spec-provider.js';
diff --git a/blocksuite/affine/shared/src/utils/spec/spec-builder.ts b/blocksuite/affine/shared/src/utils/spec/spec-builder.ts
deleted file mode 100644
index 4dd277341e..0000000000
--- a/blocksuite/affine/shared/src/utils/spec/spec-builder.ts
+++ /dev/null
@@ -1,39 +0,0 @@
-import type { ExtensionType } from '@blocksuite/store';
-
-export class SpecBuilder {
-  private _value: ExtensionType[];
-
-  get value() {
-    return this._value;
-  }
-
-  constructor(spec: ExtensionType[]) {
-    this._value = [...spec];
-  }
-
-  extend(extensions: ExtensionType[]) {
-    this._value = [...this._value, ...extensions];
-    return this;
-  }
-
-  omit(target: ExtensionType) {
-    this._value = this._value.filter(extension => extension !== target);
-    return this;
-  }
-
-  hasAll(target: ExtensionType[]) {
-    return target.every(t => this._value.includes(t));
-  }
-
-  hasOneOf(target: ExtensionType[]) {
-    return target.some(t => this._value.includes(t));
-  }
-
-  replace(target: ExtensionType[], newExtension: ExtensionType[]) {
-    this._value = [
-      ...this._value.filter(extension => !target.includes(extension)),
-      ...newExtension,
-    ];
-    return this;
-  }
-}
diff --git a/blocksuite/affine/shared/src/utils/spec/spec-provider.ts b/blocksuite/affine/shared/src/utils/spec/spec-provider.ts
deleted file mode 100644
index 0fdcfe16ae..0000000000
--- a/blocksuite/affine/shared/src/utils/spec/spec-provider.ts
+++ /dev/null
@@ -1,86 +0,0 @@
-import { BlockSuiteError } from '@blocksuite/global/exceptions';
-import type { ExtensionType } from '@blocksuite/store';
-
-import { SpecBuilder } from './spec-builder.js';
-
-type SpecId =
-  | 'store'
-  | 'page'
-  | 'edgeless'
-  | 'preview:page'
-  | 'preview:edgeless';
-
-export class SpecProvider {
-  static instance: SpecProvider;
-
-  private readonly specMap = new Map<SpecId, ExtensionType[]>();
-
-  private constructor() {}
-
-  static get _() {
-    if (!SpecProvider.instance) {
-      SpecProvider.instance = new SpecProvider();
-    }
-    return SpecProvider.instance;
-  }
-
-  addSpec(id: SpecId, spec: ExtensionType[]) {
-    if (!this.specMap.has(id)) {
-      this.specMap.set(id, spec);
-    }
-  }
-
-  clearSpec(id: SpecId) {
-    this.specMap.delete(id);
-  }
-
-  extendSpec(id: SpecId, newSpec: ExtensionType[]) {
-    const existingSpec = this.specMap.get(id);
-    if (!existingSpec) {
-      console.error(`Spec not found for ${id}`);
-      return;
-    }
-    this.specMap.set(id, [...existingSpec, ...newSpec]);
-  }
-
-  getSpec(id: SpecId) {
-    const spec = this.specMap.get(id);
-    if (!spec) {
-      throw new BlockSuiteError(
-        BlockSuiteError.ErrorCode.ValueNotExists,
-        `Spec not found for ${id}`
-      );
-    }
-    return new SpecBuilder(spec);
-  }
-
-  hasSpec(id: SpecId) {
-    return this.specMap.has(id);
-  }
-
-  omitSpec(id: SpecId, targetSpec: ExtensionType) {
-    const existingSpec = this.specMap.get(id);
-    if (!existingSpec) {
-      console.error(`Spec not found for ${id}`);
-      return;
-    }
-
-    this.specMap.set(
-      id,
-      existingSpec.filter(spec => spec !== targetSpec)
-    );
-  }
-
-  replaceSpec(id: SpecId, targetSpec: ExtensionType, newSpec: ExtensionType) {
-    const existingSpec = this.specMap.get(id);
-    if (!existingSpec) {
-      console.error(`Spec not found for ${id}`);
-      return;
-    }
-
-    this.specMap.set(
-      id,
-      existingSpec.map(spec => (spec === targetSpec ? newSpec : spec))
-    );
-  }
-}
diff --git a/blocksuite/integration-test/src/__tests__/utils/setup.ts b/blocksuite/integration-test/src/__tests__/utils/setup.ts
index af06acd4df..992a8c0c4a 100644
--- a/blocksuite/integration-test/src/__tests__/utils/setup.ts
+++ b/blocksuite/integration-test/src/__tests__/utils/setup.ts
@@ -1,7 +1,6 @@
 import '@toeverything/theme/style.css';
 import '@toeverything/theme/fonts.css';
 
-import { registerStoreSpecs } from '@blocksuite/affine/extensions';
 import type { DocMode } from '@blocksuite/affine/model';
 import { AffineSchemas } from '@blocksuite/affine/schemas';
 import {
@@ -24,8 +23,6 @@ import { TestAffineEditorContainer } from '../../index.js';
 import { getTestStoreManager } from '../../store.js';
 import { getTestViewManager } from '../../view.js';
 
-// FIXME: used for test import/export
-registerStoreSpecs();
 const storeManager = getTestStoreManager();
 const viewManager = getTestViewManager();
 effects();
diff --git a/blocksuite/playground/apps/starter/main.ts b/blocksuite/playground/apps/starter/main.ts
index b59c2fad0e..d23f877f57 100644
--- a/blocksuite/playground/apps/starter/main.ts
+++ b/blocksuite/playground/apps/starter/main.ts
@@ -2,7 +2,6 @@ import '../../style.css';
 
 import * as databaseBlocks from '@blocksuite/affine/blocks/database';
 import * as noteBlocks from '@blocksuite/affine/blocks/note';
-import { registerStoreSpecs } from '@blocksuite/affine/extensions';
 import * as globalUtils from '@blocksuite/affine/global/utils';
 import * as services from '@blocksuite/affine/shared/services';
 import * as blockStd from '@blocksuite/affine/std';
@@ -21,7 +20,6 @@ import {
 import { mountDefaultDocEditor } from './utils/setup-playground';
 import { prepareTestApp } from './utils/test';
 
-registerStoreSpecs();
 itEffects();
 const storeManager = getTestStoreManager();
 commentEffects();
diff --git a/packages/frontend/apps/android/src/setup.ts b/packages/frontend/apps/android/src/setup.ts
index 7032e81feb..36544281fb 100644
--- a/packages/frontend/apps/android/src/setup.ts
+++ b/packages/frontend/apps/android/src/setup.ts
@@ -1,5 +1,4 @@
 import '@affine/core/bootstrap/browser';
-import '@affine/core/bootstrap/blocksuite';
 import '@affine/component/theme';
 import '@affine/core/mobile/styles/mobile.css';
 import './proxy';
diff --git a/packages/frontend/apps/electron-renderer/src/app/setup.ts b/packages/frontend/apps/electron-renderer/src/app/setup.ts
index 8c0efdd221..78fb623056 100644
--- a/packages/frontend/apps/electron-renderer/src/app/setup.ts
+++ b/packages/frontend/apps/electron-renderer/src/app/setup.ts
@@ -1,5 +1,4 @@
 import '@affine/core/bootstrap/electron';
-import '@affine/core/bootstrap/blocksuite';
 import '@affine/core/bootstrap/cleanup';
 import '@affine/component/theme';
 import './global.css';
diff --git a/packages/frontend/apps/ios/src/setup.ts b/packages/frontend/apps/ios/src/setup.ts
index 037cf5c436..868df4f032 100644
--- a/packages/frontend/apps/ios/src/setup.ts
+++ b/packages/frontend/apps/ios/src/setup.ts
@@ -1,4 +1,3 @@
 import '@affine/core/bootstrap/browser';
-import '@affine/core/bootstrap/blocksuite';
 import '@affine/core/bootstrap/cleanup';
 import './proxy';
diff --git a/packages/frontend/apps/mobile/src/setup.ts b/packages/frontend/apps/mobile/src/setup.ts
index 91115ee8c5..f2367090f7 100644
--- a/packages/frontend/apps/mobile/src/setup.ts
+++ b/packages/frontend/apps/mobile/src/setup.ts
@@ -1,5 +1,4 @@
 import '@affine/core/bootstrap/browser';
-import '@affine/core/bootstrap/blocksuite';
 import '@affine/core/bootstrap/cleanup';
 import '@affine/component/theme';
 import '@affine/core/mobile/styles/mobile.css';
diff --git a/packages/frontend/apps/web/src/setup.ts b/packages/frontend/apps/web/src/setup.ts
index 765f04e23d..41dd0c6d4c 100644
--- a/packages/frontend/apps/web/src/setup.ts
+++ b/packages/frontend/apps/web/src/setup.ts
@@ -1,4 +1,3 @@
 import '@affine/core/bootstrap/browser';
-import '@affine/core/bootstrap/blocksuite';
 import '@affine/core/bootstrap/cleanup';
 import '@affine/component/theme';
diff --git a/packages/frontend/core/src/blocksuite/ai/effects.ts b/packages/frontend/core/src/blocksuite/ai/effects.ts
index f4bcd9298b..34ba44bc3d 100644
--- a/packages/frontend/core/src/blocksuite/ai/effects.ts
+++ b/packages/frontend/core/src/blocksuite/ai/effects.ts
@@ -1,5 +1,3 @@
-import { SpecProvider } from '@blocksuite/affine/shared/utils';
-
 import { AIChatBlockComponent } from './blocks/ai-chat-block/ai-chat-block';
 import { EdgelessAIChatBlockComponent } from './blocks/ai-chat-block/ai-chat-edgeless-block';
 import { LitTranscriptionBlock } from './blocks/ai-chat-block/ai-transcription-block';
@@ -13,7 +11,6 @@ import {
 } from './blocks/ai-chat-block/components/chat-images';
 import { ImagePlaceholder } from './blocks/ai-chat-block/components/image-placeholder';
 import { UserInfo } from './blocks/ai-chat-block/components/user-info';
-import { AIChatBlockSchemaExtension } from './blocks/ai-chat-block/model';
 import { ChatPanel } from './chat-panel';
 import { ActionWrapper } from './chat-panel/actions/action-wrapper';
 import { ActionImage } from './chat-panel/actions/image';
@@ -158,6 +155,4 @@ export function registerAIEffects() {
   );
 
   customElements.define('transcription-block', LitTranscriptionBlock);
-
-  SpecProvider._.extendSpec('store', [AIChatBlockSchemaExtension]);
 }
diff --git a/packages/frontend/core/src/blocksuite/ai/extensions/enable-ai.ts b/packages/frontend/core/src/blocksuite/ai/extensions/enable-ai.ts
deleted file mode 100644
index 0d1314c583..0000000000
--- a/packages/frontend/core/src/blocksuite/ai/extensions/enable-ai.ts
+++ /dev/null
@@ -1,42 +0,0 @@
-import { CodeBlockSpec } from '@blocksuite/affine/blocks/code';
-import { ImageBlockSpec } from '@blocksuite/affine/blocks/image';
-import { ParagraphBlockSpec } from '@blocksuite/affine/blocks/paragraph';
-import {
-  EdgelessRootBlockSpec,
-  PageRootBlockSpec,
-} from '@blocksuite/affine/blocks/root';
-import type { SpecBuilder } from '@blocksuite/affine/shared/utils';
-import type { FrameworkProvider } from '@toeverything/infra';
-
-import { AIChatBlockSpec } from '../blocks';
-import { AITranscriptionBlockSpec } from '../blocks/ai-chat-block/ai-transcription-block';
-import { AICodeBlockSpec } from './ai-code';
-import { createAIEdgelessRootBlockSpec } from './ai-edgeless-root';
-import { AIImageBlockSpec } from './ai-image';
-import { createAIPageRootBlockSpec } from './ai-page-root';
-import { AIParagraphBlockSpec } from './ai-paragraph';
-
-export function enableAIExtension(
-  specBuilder: SpecBuilder,
-  framework: FrameworkProvider,
-  enableAI: boolean
-) {
-  if (!enableAI) return;
-
-  specBuilder.replace(CodeBlockSpec, AICodeBlockSpec);
-  specBuilder.replace(ImageBlockSpec, AIImageBlockSpec);
-  specBuilder.replace(ParagraphBlockSpec, AIParagraphBlockSpec);
-
-  if (specBuilder.hasAll(EdgelessRootBlockSpec)) {
-    const aiEdgeless = createAIEdgelessRootBlockSpec(framework);
-    specBuilder.replace(EdgelessRootBlockSpec, aiEdgeless);
-  }
-
-  if (specBuilder.hasAll(PageRootBlockSpec)) {
-    const aiPage = createAIPageRootBlockSpec(framework);
-    specBuilder.replace(PageRootBlockSpec, aiPage);
-  }
-
-  specBuilder.extend(AIChatBlockSpec);
-  specBuilder.extend(AITranscriptionBlockSpec);
-}
diff --git a/packages/frontend/core/src/blocksuite/ai/extensions/index.ts b/packages/frontend/core/src/blocksuite/ai/extensions/index.ts
deleted file mode 100644
index 566868dc50..0000000000
--- a/packages/frontend/core/src/blocksuite/ai/extensions/index.ts
+++ /dev/null
@@ -1 +0,0 @@
-export * from './enable-ai';
diff --git a/packages/frontend/core/src/blocksuite/ai/index.ts b/packages/frontend/core/src/blocksuite/ai/index.ts
index 44cedbe710..5e42d78c39 100644
--- a/packages/frontend/core/src/blocksuite/ai/index.ts
+++ b/packages/frontend/core/src/blocksuite/ai/index.ts
@@ -3,7 +3,6 @@ export * from './actions';
 export { ChatPanel } from './chat-panel';
 export * from './entries';
 export * from './entries/edgeless/actions-config';
-export * from './extensions';
 export * from './messages';
 export { AIChatBlockPeekViewTemplate } from './peek-view/chat-block-peek-view';
 export * from './provider';
diff --git a/packages/frontend/core/src/blocksuite/extensions/entry/enable-affine.ts b/packages/frontend/core/src/blocksuite/extensions/entry/enable-affine.ts
deleted file mode 100644
index 9a1a525df9..0000000000
--- a/packages/frontend/core/src/blocksuite/extensions/entry/enable-affine.ts
+++ /dev/null
@@ -1,23 +0,0 @@
-import type { SpecBuilder } from '@blocksuite/affine/shared/utils';
-import { type FrameworkProvider } from '@toeverything/infra';
-
-import { buildDocDisplayMetaExtension } from '../display-meta';
-import { getEditorConfigExtension } from '../editor-config';
-import { getFontConfigExtension } from '../font-config';
-import { getTelemetryExtension } from '../telemetry';
-import { getThemeExtension } from '../theme';
-
-export function enableAffineExtension(
-  specBuilder: SpecBuilder,
-  framework: FrameworkProvider
-): void {
-  specBuilder.extend(
-    [
-      getThemeExtension(framework),
-      getFontConfigExtension(),
-      getTelemetryExtension(),
-      getEditorConfigExtension(framework),
-      buildDocDisplayMetaExtension(framework),
-    ].flat()
-  );
-}
diff --git a/packages/frontend/core/src/blocksuite/extensions/entry/enable-preview.ts b/packages/frontend/core/src/blocksuite/extensions/entry/enable-preview.ts
index 8e6c26158f..236aae424e 100644
--- a/packages/frontend/core/src/blocksuite/extensions/entry/enable-preview.ts
+++ b/packages/frontend/core/src/blocksuite/extensions/entry/enable-preview.ts
@@ -1,4 +1,3 @@
-import { PeekViewService } from '@affine/core/modules/peek-view/services/peek-view';
 import { AppThemeService } from '@affine/core/modules/theme';
 import type { Container } from '@blocksuite/affine/global/di';
 import { ColorScheme } from '@blocksuite/affine/model';
@@ -9,24 +8,15 @@ import {
 import {
   createSignalFromObservable,
   type Signal,
-  SpecProvider,
 } from '@blocksuite/affine/shared/utils';
 import {
   type BlockStdScope,
   LifeCycleWatcher,
   StdIdentifier,
 } from '@blocksuite/affine/std';
-import type { ExtensionType } from '@blocksuite/affine/store';
 import type { FrameworkProvider } from '@toeverything/infra';
 import type { Observable } from 'rxjs';
 
-import { AIChatBlockSpec } from '../../ai/blocks';
-import { AITranscriptionBlockSpec } from '../../ai/blocks/ai-chat-block/ai-transcription-block';
-import { buildDocDisplayMetaExtension } from '../display-meta';
-import { getFontConfigExtension } from '../font-config';
-import { patchPeekViewService } from '../peek-view-service';
-import { getThemeExtension } from '../theme';
-
 export function getPagePreviewThemeExtension(framework: FrameworkProvider) {
   class AffinePagePreviewThemeExtension
     extends LifeCycleWatcher
@@ -81,38 +71,3 @@ export function getPagePreviewThemeExtension(framework: FrameworkProvider) {
 
   return AffinePagePreviewThemeExtension;
 }
-
-const fontConfig = getFontConfigExtension();
-
-let _framework: FrameworkProvider;
-let _previewExtensions: ExtensionType[];
-export function enablePreviewExtension(framework: FrameworkProvider): void {
-  if (_framework === framework && _previewExtensions) {
-    return;
-  }
-
-  const specProvider = SpecProvider._;
-
-  if (_previewExtensions) {
-    _previewExtensions.forEach(extension => {
-      specProvider.omitSpec('preview:page', extension);
-      specProvider.omitSpec('preview:edgeless', extension);
-    });
-  }
-
-  _framework = framework;
-  const peekViewService = framework.get(PeekViewService);
-
-  _previewExtensions = [
-    ...AIChatBlockSpec,
-    ...AITranscriptionBlockSpec,
-    fontConfig,
-    getThemeExtension(framework),
-    getPagePreviewThemeExtension(framework),
-    buildDocDisplayMetaExtension(framework),
-    patchPeekViewService(peekViewService),
-  ];
-
-  specProvider.extendSpec('preview:page', _previewExtensions);
-  specProvider.extendSpec('preview:edgeless', _previewExtensions);
-}
diff --git a/packages/frontend/core/src/blocksuite/extensions/index.ts b/packages/frontend/core/src/blocksuite/extensions/index.ts
index bbc9b34f6b..025a1597dc 100644
--- a/packages/frontend/core/src/blocksuite/extensions/index.ts
+++ b/packages/frontend/core/src/blocksuite/extensions/index.ts
@@ -1,2 +1 @@
-export * from './entry/enable-affine';
 export * from './entry/enable-mobile';
diff --git a/packages/frontend/core/src/bootstrap/blocksuite.ts b/packages/frontend/core/src/bootstrap/blocksuite.ts
deleted file mode 100644
index ad5d5ec3af..0000000000
--- a/packages/frontend/core/src/bootstrap/blocksuite.ts
+++ /dev/null
@@ -1,3 +0,0 @@
-import { registerStoreSpecs } from '@blocksuite/affine/extensions';
-
-registerStoreSpecs();