diff --git a/packages/core/__tests__/cli/build-watch.test.ts b/packages/core/__tests__/cli/build-watch.test.ts
index ce0cb49c9..220f2aac4 100644
--- a/packages/core/__tests__/cli/build-watch.test.ts
+++ b/packages/core/__tests__/cli/build-watch.test.ts
@@ -194,16 +194,16 @@ describe('CLI: watched build mode typechecking', () => {
 
       await pauseForTSBuffering();
 
-      project.write(INPUT_SFC, code.replace('this.startupTime', 'this.startupTimee'));
-
-      output = await watch.awaitOutput('Watching for file changes.');
+      output = await watch.writeAndAwaitOutput(
+        INPUT_SFC,
+        code.replace('this.startupTime', 'this.startupTimee'),
+        'Watching for file changes.'
+      );
       expect(output).toMatch('Found 1 error.');
 
       await pauseForTSBuffering();
 
-      project.write(INPUT_SFC, code);
-
-      output = await watch.awaitOutput('Watching for file changes.');
+      output = await watch.writeAndAwaitOutput(INPUT_SFC, code, 'Watching for file changes.');
       expect(output).toMatch('Found 0 errors.');
 
       await watch.terminate();
@@ -237,9 +237,11 @@ describe('CLI: watched build mode typechecking', () => {
 
       await pauseForTSBuffering();
 
-      project.write(INPUT_SFC, code.replace('{{! @glint-nocheck }}', ''));
-
-      output = await watch.awaitOutput('Watching for file changes.');
+      output = await watch.writeAndAwaitOutput(
+        INPUT_SFC,
+        code.replace('{{! @glint-nocheck }}', ''),
+        'Watching for file changes.'
+      );
       expect(output).toMatch('Found 1 error.');
 
       await watch.terminate();
diff --git a/packages/core/__tests__/cli/custom-extensions.test.ts b/packages/core/__tests__/cli/custom-extensions.test.ts
index ec01eabd1..27ccd4f13 100644
--- a/packages/core/__tests__/cli/custom-extensions.test.ts
+++ b/packages/core/__tests__/cli/custom-extensions.test.ts
@@ -81,9 +81,7 @@ describe('CLI: custom extensions', () => {
         "Cannot find module './other' or its corresponding type declarations."
       );
 
-      project.write('other.gjs', 'export const foo = 123;');
-
-      await watch.awaitOutput('Found 0 errors.');
+      await watch.writeAndAwaitOutput('other.gjs', 'export const foo = 123;', 'Found 0 errors.');
       await watch.terminate();
     });
 
@@ -95,8 +93,11 @@ describe('CLI: custom extensions', () => {
 
       expect(output).toMatch('Found 0 errors.');
 
-      project.write('other.gjs', 'export const foo = "hi";');
-      output = await watch.awaitOutput('Watching for file changes.');
+      output = await watch.writeAndAwaitOutput(
+        'other.gjs',
+        'export const foo = "hi";',
+        'Watching for file changes.'
+      );
 
       expect(output).toMatch('Found 1 error.');
       expect(output).toMatch('TS2362');
diff --git a/packages/core/__tests__/cli/watch.test.ts b/packages/core/__tests__/cli/watch.test.ts
index 090266961..fc5b56611 100644
--- a/packages/core/__tests__/cli/watch.test.ts
+++ b/packages/core/__tests__/cli/watch.test.ts
@@ -154,14 +154,14 @@ describe('CLI: watched typechecking', () => {
     let output = await watch.awaitOutput('Watching for file changes.');
     expect(output).toMatch('Found 0 errors.');
 
-    project.write('index.ts', code.replace('this.startupTime', 'this.startupTimee'));
-
-    output = await watch.awaitOutput('Watching for file changes.');
+    output = await watch.writeAndAwaitOutput(
+      'index.ts',
+      code.replace('this.startupTime', 'this.startupTimee'),
+      'Watching for file changes.'
+    );
     expect(output).toMatch('Found 1 error.');
 
-    project.write('index.ts', code);
-
-    output = await watch.awaitOutput('Watching for file changes.');
+    output = await watch.writeAndAwaitOutput('index.ts', code, 'Watching for file changes.');
     expect(output).toMatch('Found 0 errors.');
 
     expect(watch.allOutput).toMatch(/\033c/); // output should include screen reset control sequence
@@ -196,19 +196,25 @@ describe('CLI: watched typechecking', () => {
     let output = await watch.awaitOutput('Watching for file changes.');
     expect(output).toMatch('Found 0 errors.');
 
-    project.write('my-component.hbs', template.replace('target', 'tarrget'));
-
-    output = await watch.awaitOutput('Watching for file changes.');
+    output = await watch.writeAndAwaitOutput(
+      'my-component.hbs',
+      template.replace('target', 'tarrget'),
+      'Watching for file changes.'
+    );
     expect(output).toMatch('Found 1 error.');
 
-    project.write('my-component.hbs', template);
-
-    output = await watch.awaitOutput('Watching for file changes.');
+    output = await watch.writeAndAwaitOutput(
+      'my-component.hbs',
+      template,
+      'Watching for file changes.'
+    );
     expect(output).toMatch('Found 0 errors.');
 
-    project.write('my-component.hbs', template.replace('@message', '@messagee'));
-
-    output = await watch.awaitOutput('Watching for file changes.');
+    output = await watch.writeAndAwaitOutput(
+      'my-component.hbs',
+      template.replace('@message', '@messagee'),
+      'Watching for file changes.'
+    );
     expect(output).toMatch('Found 1 error.');
 
     project.remove('my-component.hbs');
@@ -238,14 +244,14 @@ describe('CLI: watched typechecking', () => {
     let output = await watch.awaitOutput('Watching for file changes.');
     expect(output).toMatch('Found 0 errors.');
 
-    project.write('index.gts', code.replace('this.startupTime', 'this.startupTimee'));
-
-    output = await watch.awaitOutput('Watching for file changes.');
+    output = await watch.writeAndAwaitOutput(
+      'index.gts',
+      code.replace('this.startupTime', 'this.startupTimee'),
+      'Watching for file changes.'
+    );
     expect(output).toMatch('Found 1 error.');
 
-    project.write('index.gts', code);
-
-    output = await watch.awaitOutput('Watching for file changes.');
+    output = await watch.writeAndAwaitOutput('index.gts', code, 'Watching for file changes.');
     expect(output).toMatch('Found 0 errors.');
 
     await watch.terminate();
@@ -278,14 +284,18 @@ describe('CLI: watched typechecking', () => {
     let output = await watch.awaitOutput('Watching for file changes.');
     expect(output).toMatch('Found 0 errors.');
 
-    project.write('my-component.ts', script.replace('// ', ''));
-
-    output = await watch.awaitOutput('Watching for file changes.');
+    output = await watch.writeAndAwaitOutput(
+      'my-component.ts',
+      script.replace('// ', ''),
+      'Watching for file changes.'
+    );
     expect(output).toMatch('Found 1 error.');
 
-    project.write('my-component.ts', script);
-
-    output = await watch.awaitOutput('Watching for file changes.');
+    output = await watch.writeAndAwaitOutput(
+      'my-component.ts',
+      script,
+      'Watching for file changes.'
+    );
     expect(output).toMatch('Found 0 errors.');
 
     await watch.terminate();
@@ -316,14 +326,14 @@ describe('CLI: watched typechecking', () => {
     let output = await watch.awaitOutput('Watching for file changes.');
     expect(output).toMatch('Found 0 errors.');
 
-    project.write('index.ts', code.replace('this.startupTime', 'this.startupTimee'));
-
-    output = await watch.awaitOutput('Watching for file changes.');
+    output = await watch.writeAndAwaitOutput(
+      'index.ts',
+      code.replace('this.startupTime', 'this.startupTimee'),
+      'Watching for file changes.'
+    );
     expect(output).toMatch('Found 1 error.');
 
-    project.write('index.ts', code);
-
-    output = await watch.awaitOutput('Watching for file changes.');
+    output = await watch.writeAndAwaitOutput('index.ts', code, 'Watching for file changes.');
     expect(output).toMatch('Found 0 errors.');
 
     expect(watch.allOutput).not.toMatch(/\033c/); // output should not include screen reset control sequence