diff --git a/src/project.ts b/src/project.ts
index 2ad9e25a..2a530c3e 100644
--- a/src/project.ts
+++ b/src/project.ts
@@ -9,6 +9,8 @@ import {
   isRootStartingWithFilePath,
   getDepIfExists,
   getPackageJSON,
+  cached,
+  PackageInfo,
 } from './utils/layout-helpers';
 import Server from './server';
 import { Diagnostic, FileChangeType } from 'vscode-languageserver/node';
@@ -39,6 +41,7 @@ export class Project {
   initIssues: Error[] = [];
   files: Map<string, { version: number }> = new Map();
   podModulePrefix = '';
+  @cached
   get roots() {
     const mainRoot = this.root;
     const otherRoots = this.addonsMeta.map((meta) => meta.root);
@@ -105,7 +108,8 @@ export class Project {
   addWatcher(cb: Watcher) {
     this.watchers.push(cb);
   }
-  get packageJSON() {
+  @cached
+  get packageJSON(): PackageInfo {
     return getPackageJSON(this.root);
   }
   get name() {
diff --git a/src/server.ts b/src/server.ts
index e096640f..5b2bcae9 100644
--- a/src/server.ts
+++ b/src/server.ts
@@ -54,6 +54,7 @@ import { Usage, findRelatedFiles } from './utils/usages-api';
 import { URI } from 'vscode-uri';
 import { MatchResultType } from './utils/path-matcher';
 import { FileChangeType } from 'vscode-languageserver/node';
+import { debounce } from 'lodash';
 
 export default class Server {
   initializers: any[] = [];
@@ -136,10 +137,16 @@ export default class Server {
       this.connection.workspace.onDidChangeWorkspaceFolders(this.onDidChangeWorkspaceFolders.bind(this));
     }
 
-    this.executors['els.setConfig'] = async (_, __, [config]: [{ local: { addons: string[]; ignoredProjects: string[] } }]) => {
+    this.executors['els.setConfig'] = async (_, __, [config]: [{ local: { addons: string[]; ignoredProjects: string[]; useBuiltinLinting: boolean } }]) => {
       this.projectRoots.setLocalAddons(config.local.addons);
       this.projectRoots.setIgnoredProjects(config.local.ignoredProjects);
 
+      if (config.local.useBuiltinLinting === false) {
+        this.templateLinter.disable();
+      } else if (config.local.useBuiltinLinting === true) {
+        this.templateLinter.enable();
+      }
+
       if (this.lazyInit) {
         this.executeInitializers();
       }
@@ -264,11 +271,14 @@ export default class Server {
 
     this.documents.listen(this.connection);
 
+    this.onDidChangeContent = this.onDidChangeContent.bind(this);
+    this._onDidChangeContent = this._onDidChangeContent.bind(this);
+
     // Bind event handlers
     this.connection.onInitialize(this.onInitialize.bind(this));
     this.connection.onInitialized(this.onInitialized.bind(this));
-    this.documents.onDidChangeContent(this.onDidChangeContent.bind(this));
-    this.documents.onDidOpen(this.onDidChangeContent.bind(this));
+    this.documents.onDidChangeContent(this.onDidChangeContent);
+    this.documents.onDidOpen(this.onDidChangeContent);
     this.connection.onDidChangeWatchedFiles(this.onDidChangeWatchedFiles.bind(this));
     this.connection.onDocumentSymbol(this.onDocumentSymbol.bind(this));
     this.connection.onDefinition(this.definitionProvider.handler);
@@ -443,23 +453,32 @@ export default class Server {
     return results;
   }
 
+  lastChangeEvent!: TextDocumentChangeEvent<TextDocument>;
+
   private async onDidChangeContent(change: TextDocumentChangeEvent<TextDocument>) {
+    this.lastChangeEvent = change;
+    debounce(this._onDidChangeContent, 250);
+  }
+
+  private async _onDidChangeContent() {
     // this.setStatusText('did-change');
+    const change = this.lastChangeEvent;
 
     const lintResults = await this.templateLinter.lint(change.document);
-    const results: Diagnostic[] = [];
+
+    if (change !== this.lastChangeEvent) {
+      return;
+    }
 
     if (Array.isArray(lintResults)) {
-      lintResults.forEach((result) => {
-        results.push(result);
-      });
+      this.connection.sendDiagnostics({ version: change.document.version, uri: change.document.uri, diagnostics: lintResults });
     }
 
     const addonResults = await this.runAddonLinters(change.document);
 
-    addonResults.forEach((result) => {
-      results.push(result);
-    });
+    if (change !== this.lastChangeEvent) {
+      return;
+    }
 
     const project = this.projectRoots.projectForUri(change.document.uri);
 
@@ -467,7 +486,7 @@ export default class Server {
       project.trackChange(change.document.uri, FileChangeType.Changed);
     }
 
-    this.connection.sendDiagnostics({ uri: change.document.uri, diagnostics: results });
+    this.connection.sendDiagnostics({ version: change.document.version, uri: change.document.uri, diagnostics: addonResults });
   }
 
   private onDidChangeWatchedFiles(items: DidChangeWatchedFilesParams) {
diff --git a/src/template-linter.ts b/src/template-linter.ts
index 0acfa159..f65aafe3 100644
--- a/src/template-linter.ts
+++ b/src/template-linter.ts
@@ -37,9 +37,18 @@ function setCwd(cwd: string) {
 
 export default class TemplateLinter {
   private _linterCache = new Map<Project, any>();
+  private _isEnabled = true;
 
   constructor(private server: Server) {}
 
+  disable() {
+    this._isEnabled = false;
+  }
+
+  enable() {
+    this._isEnabled = true;
+  }
+
   private getProjectForDocument(textDocument: TextDocument) {
     const ext = getExtension(textDocument);
 
@@ -81,6 +90,10 @@ export default class TemplateLinter {
     }
   }
   async lint(textDocument: TextDocument): Promise<Diagnostic[] | undefined> {
+    if (this._isEnabled === false) {
+      return;
+    }
+
     const cwd = process.cwd();
     const project = this.getProjectForDocument(textDocument);
 
diff --git a/src/utils/addon-api.ts b/src/utils/addon-api.ts
index 5fef2603..5cb02109 100644
--- a/src/utils/addon-api.ts
+++ b/src/utils/addon-api.ts
@@ -6,6 +6,7 @@ import {
   PackageInfo,
   ADDON_CONFIG_KEY,
   hasEmberLanguageServerExtension,
+  addonVersion,
 } from './layout-helpers';
 import { TextDocument } from 'vscode-languageserver-textdocument';
 import * as path from 'path';
@@ -196,6 +197,7 @@ export function collectProjectProviders(root: string, addons: string[]): Project
       addonsMeta.push({
         name: info.name,
         root: packagePath,
+        version: addonVersion(info),
       });
     }
 
@@ -224,7 +226,7 @@ export function collectProjectProviders(root: string, addons: string[]): Project
     codeActionProviders: CodeActionResolveFunction[];
     initFunctions: InitFunction[];
     info: string[];
-    addonsMeta: { name: string; root: string }[];
+    addonsMeta: AddonMeta[];
   } = {
     definitionProviders: [],
     referencesProviders: [],
@@ -319,7 +321,7 @@ export function collectProjectProviders(root: string, addons: string[]): Project
   return result;
 }
 
-export type AddonMeta = { root: string; name: string };
+export type AddonMeta = { root: string; name: string; version: null | 1 | 2 };
 export type DependencyMeta = { name: string; version: string };
 export interface ProjectProviders {
   definitionProviders: DefinitionResolveFunction[];
diff --git a/src/utils/layout-helpers.ts b/src/utils/layout-helpers.ts
index b50d8321..1159ecbe 100644
--- a/src/utils/layout-helpers.ts
+++ b/src/utils/layout-helpers.ts
@@ -158,6 +158,26 @@ export function isELSAddonRoot(root: string) {
   return hasEmberLanguageServerExtension(pack);
 }
 
+export function cached(_proto: unknown, prop: string, desc: PropertyDescriptor) {
+  const values = new WeakMap();
+
+  return {
+    get() {
+      if (!values.has(this)) {
+        values.set(this, {});
+      }
+
+      const objects = values.get(this);
+
+      if (!(prop in objects)) {
+        objects[prop] = desc.get?.call(this);
+      }
+
+      return objects[prop];
+    },
+  };
+}
+
 function getRecursiveInRepoAddonRoots(root: string, roots: string[]) {
   const packageData = getPackageJSON(root);
   const emberAddonPaths: string[] = (packageData['ember-addon'] && packageData['ember-addon'].paths) || [];
@@ -384,7 +404,7 @@ export function isEmberAddon(info: PackageInfo) {
   return info.keywords && info.keywords.includes('ember-addon');
 }
 
-function addonVersion(info: PackageInfo) {
+export function addonVersion(info: PackageInfo) {
   if (!isEmberAddon(info)) {
     return null;
   }
diff --git a/test/__snapshots__/integration-test.ts.snap b/test/__snapshots__/integration-test.ts.snap
index 7a9a0cb6..863629ae 100644
--- a/test/__snapshots__/integration-test.ts.snap
+++ b/test/__snapshots__/integration-test.ts.snap
@@ -6,18 +6,22 @@ Object {
     Object {
       "name": "addon1",
       "root": "node_modules/addon1",
+      "version": null,
     },
     Object {
       "name": "addon2",
       "root": "node_modules/addon2",
+      "version": null,
     },
     Object {
       "name": "addon3",
       "root": "node_modules/addon3",
+      "version": null,
     },
     Object {
       "name": "addon4",
       "root": "node_modules/addon4",
+      "version": null,
     },
   ],
   "registry": Object {
@@ -87,6 +91,7 @@ Object {
     Object {
       "name": "provider",
       "root": "node_modules/provider",
+      "version": null,
     },
   ],
   "registry": Object {
@@ -110,6 +115,7 @@ Object {
     Object {
       "name": "provider",
       "root": "node_modules/provider",
+      "version": null,
     },
   ],
   "registry": Object {
@@ -146,6 +152,7 @@ Object {
     Object {
       "name": "provider",
       "root": "node_modules/provider",
+      "version": null,
     },
   ],
   "registry": Object {
@@ -179,6 +186,7 @@ Object {
     Object {
       "name": "provider",
       "root": "node_modules/provider",
+      "version": null,
     },
   ],
   "registry": Object {
@@ -212,6 +220,7 @@ Object {
     Object {
       "name": "provider",
       "root": "node_modules/provider",
+      "version": null,
     },
   ],
   "registry": Object {
@@ -317,10 +326,12 @@ Object {
     Object {
       "name": "biz",
       "root": "lib/biz",
+      "version": 1,
     },
     Object {
       "name": "foo",
       "root": "../lib/foo",
+      "version": 1,
     },
   ],
   "registry": Object {
@@ -743,6 +754,7 @@ Object {
     Object {
       "name": "provider",
       "root": "node_modules/provider",
+      "version": null,
     },
   ],
   "registry": Object {
@@ -776,6 +788,7 @@ Object {
     Object {
       "name": "provider",
       "root": "node_modules/provider",
+      "version": null,
     },
   ],
   "registry": Object {
@@ -2378,6 +2391,7 @@ Object {
     Object {
       "name": "biz",
       "root": "lib/biz",
+      "version": 1,
     },
   ],
   "registry": Object {
@@ -2417,6 +2431,7 @@ Object {
     Object {
       "name": "biz",
       "root": "lib/biz",
+      "version": 1,
     },
   ],
   "registry": Object {
@@ -2804,10 +2819,12 @@ Object {
     Object {
       "name": "biz",
       "root": "lib/biz",
+      "version": 1,
     },
     Object {
       "name": "foo",
       "root": "../lib/foo",
+      "version": 1,
     },
   ],
   "registry": Object {
diff --git a/tsconfig.json b/tsconfig.json
index 127b4431..99c9d272 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -1,5 +1,6 @@
 {
   "compilerOptions": {
+    "experimentalDecorators": true,
     "target": "ES2018",
     "module": "commonjs",
     "allowSyntheticDefaultImports": true,