diff --git a/ts/addon.ts b/ts/addon.ts
index de2f645a7..291268538 100644
--- a/ts/addon.ts
+++ b/ts/addon.ts
@@ -46,12 +46,16 @@ export default addon({
     return `${__dirname}/blueprints`;
   },
 
-  serverMiddleware({ app }) {
-    this._addTypecheckMiddleware(app);
+  serverMiddleware({ app, options }) {
+    if (!options || !options.path) {
+      this._addTypecheckMiddleware(app);
+    }
   },
 
-  testemMiddleware(app) {
-    this._addTypecheckMiddleware(app);
+  testemMiddleware(app, options) {
+    if (!options || !options.path) {
+      this._addTypecheckMiddleware(app);
+    }
   },
 
   async postBuild() {
diff --git a/ts/tests/acceptance/build-test.ts b/ts/tests/acceptance/build-test.ts
index 10ff9a233..8f0822b2d 100644
--- a/ts/tests/acceptance/build-test.ts
+++ b/ts/tests/acceptance/build-test.ts
@@ -69,6 +69,52 @@ describe('Acceptance: build', function() {
     );
   });
 
+  it("doesn't launch type checking when --path used", async () => {
+    await app.build();
+    let server = app.serve({
+      args: ['--path', 'dist'],
+      env: { DEBUG: 'ember-cli-typescript|express:*' },
+    });
+    let result = await server.raceForOutputs([
+      'ember-cli-typescript:typecheck-worker',
+      'Serving on',
+    ]);
+    expect(result).to.include('Serving on');
+  });
+
+  it('does launch type checking when --path not used', async () => {
+    await app.build();
+    let server = app.serve({ env: { DEBUG: 'ember-cli-typescript|express:*' } });
+    let result = await server.raceForOutputs([
+      'ember-cli-typescript:typecheck-worker',
+      'Serving on',
+    ]);
+    expect(result).to.include('ember-cli-typescript:typecheck-worker');
+  });
+
+  it("doesn't launch type checking when --path used for tests", async () => {
+    await app.build();
+    let test = app.test({
+      args: ['--path', 'dist'],
+      env: { DEBUG: 'ember-cli-typescript|express:*' },
+    });
+    let result = await test.raceForOutputs([
+      'ember-cli-typescript:typecheck-worker',
+      'express:application',
+    ]);
+    expect(result).to.include('express:application');
+  });
+
+  it('does launch type checking when --path not used for tests', async () => {
+    await app.build();
+    let test = app.test({ env: { DEBUG: 'ember-cli-typescript|express:*' } });
+    let result = await test.raceForOutputs([
+      'ember-cli-typescript:typecheck-worker',
+      'express:application',
+    ]);
+    expect(result).to.include('ember-cli-typescript:typecheck-worker');
+  });
+
   it('fails the build when noEmitOnError is set and an error is emitted', async () => {
     app.writeFile('app/app.ts', `import { foo } from 'nonexistent';`);
 
diff --git a/ts/tests/helpers/skeleton-app.ts b/ts/tests/helpers/skeleton-app.ts
index e5435c549..9e7ab5662 100644
--- a/ts/tests/helpers/skeleton-app.ts
+++ b/ts/tests/helpers/skeleton-app.ts
@@ -15,9 +15,15 @@ const getEmberPort = (() => {
   return () => lastPort++;
 })();
 
+interface EmberCliOptions {
+  args?: string[];
+  env?: any;
+}
+
 export default class SkeletonApp {
   port = getEmberPort();
-  watched: WatchedBuild | null = null;
+  watched: WatchedEmberProcess | null = null;
+  watchedTest: WatchedEmberProcess | null = null;
   tmpDir = tmp.dirSync({
     tries: 10,
     unsafeCleanup: true,
@@ -31,17 +37,25 @@ export default class SkeletonApp {
   }
 
   build() {
-    return this._ember(['build']);
+    return this._ember({ args: ['build'] });
   }
 
-  serve() {
+  serve(options: EmberCliOptions = { args: [], env: {} }) {
     if (this.watched) {
       throw new Error('Already serving');
     }
-    return (this.watched = new WatchedBuild(
-      this._ember(['serve', '--port', `${this.port}`]),
-      this.port
-    ));
+    options.args = options.args || [];
+    options.args = ['serve', '--port', `${this.port}`, ...options.args];
+    return (this.watched = new WatchedEmberProcess(this._ember(options), this.port));
+  }
+
+  test(options: EmberCliOptions = { args: [], env: {} }) {
+    if (this.watchedTest) {
+      throw new Error('Already testing');
+    }
+    options.args = options.args || [];
+    options.args = ['test', ...options.args];
+    return (this.watchedTest = new WatchedEmberProcess(this._ember(options)));
   }
 
   updatePackageJSON(callback: (arg: any) => any) {
@@ -68,17 +82,20 @@ export default class SkeletonApp {
     if (this.watched) {
       this.watched.kill();
     }
+    if (this.watchedTest) {
+      this.watchedTest.kill();
+    }
     this.tmpDir.removeCallback();
   }
 
-  _ember(args: string[]) {
+  _ember(options: EmberCliOptions) {
     let ember = require.resolve('ember-cli/bin/ember');
-    return execa.node(ember, args, { cwd: this.root, all: true });
+    return execa.node(ember, options.args, { cwd: this.root, all: true, env: options.env });
   }
 }
 
-class WatchedBuild extends EventEmitter {
-  constructor(protected ember: execa.ExecaChildProcess, protected port: number) {
+class WatchedEmberProcess extends EventEmitter {
+  constructor(protected ember: execa.ExecaChildProcess, protected port?: number) {
     super();
     this.ember.stdout.on('data', data => {
       let output = data.toString();
@@ -102,6 +119,10 @@ class WatchedBuild extends EventEmitter {
     return got(`http://localhost:${this.port}${path}`);
   }
 
+  raceForOutputs(targets: string[]) {
+    return Promise.race(targets.map(target => this.waitForOutput(target)));
+  }
+
   waitForOutput(target: string) {
     return new Promise(resolve => {
       let output = '';
diff --git a/ts/types/ember-cli/index.d.ts b/ts/types/ember-cli/index.d.ts
index 1c78069ef..bb75f7694 100644
--- a/ts/types/ember-cli/index.d.ts
+++ b/ts/types/ember-cli/index.d.ts
@@ -11,6 +11,7 @@ declare module 'ember-cli/lib/models/addon' {
   import UI from 'console-ui';
   import { Application } from 'express';
   import Project from 'ember-cli/lib/models/project';
+  import { TaskOptions } from 'ember-cli/lib/models/task';
   import Command from 'ember-cli/lib/models/command';
   import EmberApp from 'ember-cli/lib/broccoli/ember-app';
   import PreprocessRegistry from 'ember-cli-preprocess-registry';
@@ -36,8 +37,8 @@ declare module 'ember-cli/lib/models/addon' {
     includedCommands(): Record<string, typeof Command | ExtendOptions<Command>> | void;
     shouldIncludeChildAddon(addon: Addon): boolean;
     isDevelopingAddon(): boolean;
-    serverMiddleware(options: { app: Application }): void | Promise<void>;
-    testemMiddleware(app: Application): void;
+    serverMiddleware(options: { app: Application; options?: TaskOptions }): void | Promise<void>;
+    testemMiddleware(app: Application, options?: TaskOptions): void;
     setupPreprocessorRegistry(type: 'self' | 'parent', registry: PreprocessRegistry): void;
   }
 }
@@ -49,6 +50,12 @@ declare module 'ember-cli/lib/models/blueprint' {
   export = Blueprint;
 }
 
+declare module 'ember-cli/lib/models/task' {
+  export interface TaskOptions {
+    path?: string;
+  }
+}
+
 declare module 'ember-cli/lib/models/command' {
   import CoreObject from 'core-object';
   import UI from 'console-ui';