diff --git a/packages/language-service/BUILD.bazel b/packages/language-service/BUILD.bazel
index 4a741ba60c29d8..3379d4e4f7f883 100644
--- a/packages/language-service/BUILD.bazel
+++ b/packages/language-service/BUILD.bazel
@@ -6,15 +6,17 @@ ts_library(
     name = "api",
     srcs = [
         "api.ts",
+        "index.ts",
     ],
     deps = [
+        "@npm//@types/node",
         "@npm//typescript",
     ],
 )
 
 ts_library(
     name = "language-service",
-    srcs = ["index.ts"] + glob(
+    srcs = glob(
         [
             "src/**/*.ts",
         ],
@@ -54,8 +56,7 @@ pkg_npm(
         "//integration:__pkg__",
     ],
     deps = [
-        ":language-service",
-        "//packages/language-service/ivy",
+        ":api",
         # min bundle is not used at the moment; omit from package to speed up build
         "//packages/language-service/bundles:language-service.js",
         "//packages/language-service/bundles:ivy.js",
diff --git a/packages/language-service/api.ts b/packages/language-service/api.ts
index 603f82dbb5d0ec..a78f3173e450e2 100644
--- a/packages/language-service/api.ts
+++ b/packages/language-service/api.ts
@@ -14,6 +14,19 @@
 
 import * as ts from 'typescript';
 
+export interface NgLanguageServiceConfig {
+  /**
+   * If true, return only Angular results. Otherwise, return Angular + TypeScript
+   * results.
+   */
+  angularOnly: boolean;
+  /**
+   * If true, return factory function for Ivy LS during plugin initialization.
+   * Otherwise return factory function for View Engine LS.
+   */
+  ivy: boolean;
+}
+
 export type GetTcbResponse = {
   /**
    * The filename of the SourceFile this typecheck block belongs to.
diff --git a/packages/language-service/bundles/BUILD.bazel b/packages/language-service/bundles/BUILD.bazel
index d1c5915e1744d8..08e47e0d3833ed 100644
--- a/packages/language-service/bundles/BUILD.bazel
+++ b/packages/language-service/bundles/BUILD.bazel
@@ -3,7 +3,7 @@ load("//dev-infra/benchmark/ng_rollup_bundle:ng_rollup_bundle.bzl", "ng_rollup_b
 ng_rollup_bundle(
     name = "language-service",
     build_optimizer = False,
-    entry_point = "//packages/language-service:index.ts",
+    entry_point = "//packages/language-service:src/ts_plugin.ts",
     format = "amd",
     globals = {
         "fs": "fs",
diff --git a/packages/language-service/index.ts b/packages/language-service/index.ts
index 0ed58aaa34a2d0..636dfc17611c2a 100644
--- a/packages/language-service/index.ts
+++ b/packages/language-service/index.ts
@@ -6,5 +6,39 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
+import * as ts from 'typescript/lib/tsserverlibrary';
+import {NgLanguageService, NgLanguageServiceConfig} from './api';
+
 export * from './api';
-export {create, getExternalFiles} from './src/ts_plugin';
+
+interface PluginModule extends ts.server.PluginModule {
+  create(createInfo: ts.server.PluginCreateInfo): NgLanguageService;
+  onConfigurationChanged?(config: NgLanguageServiceConfig): void;
+}
+
+const factory: ts.server.PluginModuleFactory = function(mod): PluginModule {
+  let plugin: PluginModule;
+
+  function create(info: ts.server.PluginCreateInfo): NgLanguageService {
+    const config: NgLanguageServiceConfig = info.config;
+    const bundleName = config.ivy ? 'ivy.js' : 'language-service.js';
+    plugin = require(`./bundles/${bundleName}`)(mod);
+    return plugin.create(info);
+  }
+
+  function getExternalFiles(proj: ts.server.Project): string[] {
+    return plugin?.getExternalFiles?.(proj) ?? [];
+  }
+
+  function onConfigurationChanged(config: NgLanguageServiceConfig): void {
+    plugin?.onConfigurationChanged?.(config);
+  }
+
+  return {
+    create,
+    getExternalFiles,
+    onConfigurationChanged,
+  };
+};
+
+module.exports = factory;
diff --git a/packages/language-service/package.json b/packages/language-service/package.json
index e3e5b2a1b56c2f..6bb933885dae8d 100644
--- a/packages/language-service/package.json
+++ b/packages/language-service/package.json
@@ -2,7 +2,7 @@
   "name": "@angular/language-service",
   "version": "0.0.0-PLACEHOLDER",
   "description": "Angular - language services",
-  "main": "./bundles/language-service.js",
+  "main": "./index.js",
   "typings": "./index.d.ts",
   "author": "angular",
   "license": "MIT",