From 2674ac042d30e9bd28f4feeb85353f61498429df Mon Sep 17 00:00:00 2001
From: gabriel miranda <gabrielmfern@outlook.com>
Date: Tue, 25 Nov 2025 10:15:50 -0300
Subject: [PATCH 01/10] fix shell usage in preview server dev

---
 packages/preview-server/scripts/dev.mts | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/packages/preview-server/scripts/dev.mts b/packages/preview-server/scripts/dev.mts
index 07fcda8c35..3dc7a4759e 100644
--- a/packages/preview-server/scripts/dev.mts
+++ b/packages/preview-server/scripts/dev.mts
@@ -30,9 +30,10 @@ NEXT_PUBLIC_IS_PREVIEW_DEVELOPMENT=true`,
   'utf8',
 );
 
-const webServerProcess = child_process.spawn('next', ['dev'], {
+const next = path.resolve(dirname, '../node_modules/.bin/next');
+
+const webServerProcess = child_process.spawn(next, ['dev'], {
   cwd: previewServerRoot,
-  shell: true,
   stdio: 'inherit',
 });
 

From 6baabeec0a48f71fb616f02147d0e66d242e8b59 Mon Sep 17 00:00:00 2001
From: gabriel miranda <gabrielmfern@outlook.com>
Date: Tue, 25 Nov 2025 10:21:35 -0300
Subject: [PATCH 02/10] fix shell usage in create-email tests

---
 packages/create-email/package.json      |  1 +
 packages/create-email/src/index.spec.ts | 43 ++++++++++---------------
 packages/create-email/tsconfig.json     |  2 ++
 pnpm-lock.yaml                          |  3 ++
 4 files changed, 23 insertions(+), 26 deletions(-)

diff --git a/packages/create-email/package.json b/packages/create-email/package.json
index e1c1609eca..7980147180 100644
--- a/packages/create-email/package.json
+++ b/packages/create-email/package.json
@@ -36,6 +36,7 @@
     "create-email": "src/index.js"
   },
   "devDependencies": {
+    "nypm": "0.6.0",
     "react": "19.0.0",
     "tsconfig": "workspace:*",
     "typescript": "5.8.3"
diff --git a/packages/create-email/src/index.spec.ts b/packages/create-email/src/index.spec.ts
index 67b78ee99a..14eea63e52 100644
--- a/packages/create-email/src/index.spec.ts
+++ b/packages/create-email/src/index.spec.ts
@@ -1,19 +1,19 @@
 import { spawnSync } from 'node:child_process';
 import { existsSync, promises as fs } from 'node:fs';
 import path from 'node:path';
+import { installDependencies, runScript } from 'nypm';
 
 describe('automatic setup', () => {
-  const starterPath = path.resolve(__dirname, '../.test');
+  const starterPath = path.resolve(import.meta.dirname, '../.test');
   test.sequential('creation', async () => {
     if (existsSync(starterPath)) {
       await fs.rm(starterPath, { recursive: true });
     }
 
     const createEmailProcess = spawnSync(
-      'node',
-      [path.resolve(__dirname, './index.js'), '.test'],
+      path.resolve(__dirname, './index.js'),
+      ['.test'],
       {
-        shell: true,
         cwd: path.resolve(__dirname, '../'),
         stdio: 'pipe',
       },
@@ -26,35 +26,26 @@ describe('automatic setup', () => {
     );
   });
 
-  test.sequential('install', { timeout: 40_000 }, () => {
-    const installProcess = spawnSync('npm', ['install'], {
-      shell: true,
-      cwd: path.resolve(starterPath),
-      stdio: 'pipe',
+  test.sequential('install', { timeout: 40_000 }, async () => {
+    await installDependencies({
+      cwd: starterPath,
+      packageManager: 'npm',
     });
-    if (installProcess.stderr) {
-      console.log(installProcess.stderr.toString());
-    }
-    expect(installProcess.status, 'starter npm install should return 0').toBe(
-      0,
-    );
   });
 
-  test.sequential('export', () => {
-    const exportProcess = spawnSync('npm', ['run export'], {
-      shell: true,
+  test.sequential('export', async () => {
+    await runScript('export', {
       cwd: starterPath,
-      stdio: 'pipe',
+      packageManager: 'npm',
     });
-    if (exportProcess.stderr) {
-      console.log(exportProcess.stderr.toString());
-    }
-    expect(exportProcess.status, 'export should return status code 0').toBe(0);
   });
 
-  test.sequential('type checking', { timeout: 10_000 }, () => {
-    const typecheckingProcess = spawnSync('npx', ['tsc'], {
-      shell: true,
+  test.sequential('type checking', { timeout: 10_000 }, async () => {
+    const tscBinary = path.resolve(
+      import.meta.dirname,
+      '../node_modules/.bin/tsc',
+    );
+    const typecheckingProcess = spawnSync(tscBinary, [], {
       cwd: starterPath,
       stdio: 'pipe',
     });
diff --git a/packages/create-email/tsconfig.json b/packages/create-email/tsconfig.json
index 8ee1333b50..663a8da103 100644
--- a/packages/create-email/tsconfig.json
+++ b/packages/create-email/tsconfig.json
@@ -3,6 +3,8 @@
   "include": ["**/*.ts", "**/*.tsx"],
   "exclude": ["dist", "build", "node_modules", ".test"],
   "compilerOptions": {
+    "moduleResolution": "nodenext",
+    "module": "node20",
     "noEmit": true,
     "types": ["vitest/globals"]
   }
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 981ac1d77d..c8c56cded9 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -476,6 +476,9 @@ importers:
         specifier: ^8.0.0
         version: 8.2.0
     devDependencies:
+      nypm:
+        specifier: 0.6.0
+        version: 0.6.0
       react:
         specifier: ^19.0.0
         version: 19.0.0

From 637cf329d4a9adafa111b202357f82da3289a290 Mon Sep 17 00:00:00 2001
From: gabriel miranda <gabrielmfern@outlook.com>
Date: Tue, 25 Nov 2025 10:33:08 -0300
Subject: [PATCH 03/10] include preview-server scripts in tsconfig, update
 module option

---
 packages/preview-server/tsconfig.json | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/packages/preview-server/tsconfig.json b/packages/preview-server/tsconfig.json
index c33e31b3f8..b3fa612a2c 100644
--- a/packages/preview-server/tsconfig.json
+++ b/packages/preview-server/tsconfig.json
@@ -28,7 +28,7 @@
     "noEmit": true,
     "strict": false,
     "target": "ESNext",
-    "module": "CommonJS",
+    "module": "esnext",
     "noUncheckedIndexedAccess": true,
     "resolveJsonModule": true,
     "types": ["vitest/globals"],
@@ -39,6 +39,7 @@
     "tailwind-internals.d.ts",
     "**/*.ts",
     "**/*.tsx",
+    "**/*.mts",
     ".next/types/**/*.ts",
     ".next/dev/types/**/*.ts",
     "next.config.mjs"

From 7ab82407d14ed1c2692def18cc01cd89bb9a727a Mon Sep 17 00:00:00 2001
From: gabriel miranda <gabrielmfern@outlook.com>
Date: Tue, 25 Nov 2025 10:33:18 -0300
Subject: [PATCH 04/10] remove shell f rom preview server's build

---
 .../scripts/build-preview-server.mts               | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/packages/preview-server/scripts/build-preview-server.mts b/packages/preview-server/scripts/build-preview-server.mts
index 36c0236651..c951f3670c 100644
--- a/packages/preview-server/scripts/build-preview-server.mts
+++ b/packages/preview-server/scripts/build-preview-server.mts
@@ -1,16 +1,16 @@
 import { spawn } from 'node:child_process';
 import fs from 'node:fs';
 import path from 'node:path';
-import url from 'node:url';
 
-const filename = url.fileURLToPath(import.meta.url);
-const dirname = path.dirname(filename);
+const nextBinaryPath = path.resolve(
+  import.meta.dirname,
+  '../node_modules/.bin/next',
+);
 
-const nextBuildProcess = spawn('pnpm', ['next', 'build'], {
+const nextBuildProcess = spawn(nextBinaryPath, ['build'], {
   detached: true,
-  shell: true,
   stdio: 'inherit',
-  cwd: path.resolve(dirname, '../'),
+  cwd: path.resolve(import.meta.dirname, '../'),
 });
 
 process.on('SIGINT', () => {
@@ -23,7 +23,7 @@ nextBuildProcess.on('exit', (code) => {
     process.exit(code);
   }
 
-  fs.rmSync(path.resolve(dirname, '../.next/cache'), {
+  fs.rmSync(path.resolve(import.meta.dirname, '../.next/cache'), {
     recursive: true,
   });
 });

From 7b1beca9431d690512741842dd723f48e80abcd4 Mon Sep 17 00:00:00 2001
From: gabriel miranda <gabrielmfern@outlook.com>
Date: Tue, 25 Nov 2025 10:37:01 -0300
Subject: [PATCH 05/10] use nypm's features for script running and dependency
 installation CLI's build

---
 packages/react-email/src/commands/build.ts | 71 ++++------------------
 1 file changed, 11 insertions(+), 60 deletions(-)

diff --git a/packages/react-email/src/commands/build.ts b/packages/react-email/src/commands/build.ts
index 262d5437b6..11fede1b5e 100644
--- a/packages/react-email/src/commands/build.ts
+++ b/packages/react-email/src/commands/build.ts
@@ -1,7 +1,7 @@
-import { spawn } from 'node:child_process';
 import fs from 'node:fs';
 import path from 'node:path';
 import logSymbols from 'log-symbols';
+import { installDependencies, type PackageManagerName, runScript } from 'nypm';
 import ora from 'ora';
 import {
   type EmailsDirectory,
@@ -12,65 +12,9 @@ import { registerSpinnerAutostopping } from '../utils/register-spinner-autostopp
 
 interface Args {
   dir: string;
-  packageManager: string;
+  packageManager: PackageManagerName;
 }
 
-const buildPreviewApp = (absoluteDirectory: string) => {
-  return new Promise<void>((resolve, reject) => {
-    const nextBuild = spawn('npm', ['run', 'build'], {
-      cwd: absoluteDirectory,
-      shell: true,
-    });
-    nextBuild.stdout.pipe(process.stdout);
-    nextBuild.stderr.pipe(process.stderr);
-
-    nextBuild.on('close', (code) => {
-      if (code === 0) {
-        resolve();
-      } else {
-        reject(
-          new Error(
-            `Unable to build the Next app and it exited with code: ${code}`,
-          ),
-        );
-      }
-    });
-  });
-};
-
-const npmInstall = async (
-  builtPreviewAppPath: string,
-  packageManager: string,
-) => {
-  return new Promise<void>((resolve, reject) => {
-    const childProc = spawn(
-      packageManager,
-      [
-        'install',
-        packageManager === 'deno' ? '' : '--include=dev',
-        packageManager === 'deno' ? '--quiet' : '--silent',
-      ],
-      {
-        cwd: builtPreviewAppPath,
-        shell: true,
-      },
-    );
-    childProc.stdout.pipe(process.stdout);
-    childProc.stderr.pipe(process.stderr);
-    childProc.on('close', (code) => {
-      if (code === 0) {
-        resolve();
-      } else {
-        reject(
-          new Error(
-            `Unable to install the dependencies and it exited with code: ${code}`,
-          ),
-        );
-      }
-    });
-  });
-};
-
 const setNextEnvironmentVariablesForBuild = async (
   emailsDirRelativePath: string,
   builtPreviewAppPath: string,
@@ -283,14 +227,21 @@ export const build = async ({
     await updatePackageJson(builtPreviewAppPath);
 
     spinner.text = 'Installing dependencies on `.react-email`';
-    await npmInstall(builtPreviewAppPath, packageManager);
+    await installDependencies({
+      cwd: builtPreviewAppPath,
+      silent: true,
+      packageManager,
+    });
 
     spinner.stopAndPersist({
       text: 'Successfully prepared `.react-email` for `next build`',
       symbol: logSymbols.success,
     });
 
-    await buildPreviewApp(builtPreviewAppPath);
+    await runScript('build', {
+      packageManager,
+      cwd: builtPreviewAppPath,
+    });
   } catch (error) {
     console.log(error);
     process.exit(1);

From 237ecb75e61aaa89c3eff02087fedcdc1fa13579 Mon Sep 17 00:00:00 2001
From: gabriel miranda <gabrielmfern@outlook.com>
Date: Wed, 26 Nov 2025 15:25:20 -0300
Subject: [PATCH 06/10] check for Windows and run .cmd with it

---
 packages/create-email/src/index.spec.ts                  | 4 +++-
 packages/preview-server/scripts/build-preview-server.mts | 4 +++-
 packages/preview-server/scripts/dev.mts                  | 9 +++++++--
 3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/packages/create-email/src/index.spec.ts b/packages/create-email/src/index.spec.ts
index 14eea63e52..b63fe4539a 100644
--- a/packages/create-email/src/index.spec.ts
+++ b/packages/create-email/src/index.spec.ts
@@ -43,7 +43,9 @@ describe('automatic setup', () => {
   test.sequential('type checking', { timeout: 10_000 }, async () => {
     const tscBinary = path.resolve(
       import.meta.dirname,
-      '../node_modules/.bin/tsc',
+      process.platform === 'win32'
+        ? '../node_modules/.bin/tsc.cmd'
+        : '../node_modules/.bin/tsc',
     );
     const typecheckingProcess = spawnSync(tscBinary, [], {
       cwd: starterPath,
diff --git a/packages/preview-server/scripts/build-preview-server.mts b/packages/preview-server/scripts/build-preview-server.mts
index c951f3670c..d11482903f 100644
--- a/packages/preview-server/scripts/build-preview-server.mts
+++ b/packages/preview-server/scripts/build-preview-server.mts
@@ -4,7 +4,9 @@ import path from 'node:path';
 
 const nextBinaryPath = path.resolve(
   import.meta.dirname,
-  '../node_modules/.bin/next',
+  process.platform === 'win32'
+    ? '../node_modules/.bin/next.cmd'
+    : '../node_modules/.bin/next',
 );
 
 const nextBuildProcess = spawn(nextBinaryPath, ['build'], {
diff --git a/packages/preview-server/scripts/dev.mts b/packages/preview-server/scripts/dev.mts
index 3dc7a4759e..fb9942daac 100644
--- a/packages/preview-server/scripts/dev.mts
+++ b/packages/preview-server/scripts/dev.mts
@@ -30,9 +30,14 @@ NEXT_PUBLIC_IS_PREVIEW_DEVELOPMENT=true`,
   'utf8',
 );
 
-const next = path.resolve(dirname, '../node_modules/.bin/next');
+const nextBinaryPath = path.resolve(
+  import.meta.dirname,
+  process.platform === 'win32'
+    ? '../node_modules/.bin/next.cmd'
+    : '../node_modules/.bin/next',
+);
 
-const webServerProcess = child_process.spawn(next, ['dev'], {
+const webServerProcess = child_process.spawn(nextBinaryPath, ['dev'], {
   cwd: previewServerRoot,
   stdio: 'inherit',
 });

From 3fa9cc505a2c8885576763883859bdcd86fcf31b Mon Sep 17 00:00:00 2001
From: gabriel miranda <gabrielmfern@outlook.com>
Date: Wed, 26 Nov 2025 15:28:12 -0300
Subject: [PATCH 07/10] don't use __dirname

---
 packages/create-email/src/index.spec.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/create-email/src/index.spec.ts b/packages/create-email/src/index.spec.ts
index b63fe4539a..4bd17c65f3 100644
--- a/packages/create-email/src/index.spec.ts
+++ b/packages/create-email/src/index.spec.ts
@@ -11,10 +11,10 @@ describe('automatic setup', () => {
     }
 
     const createEmailProcess = spawnSync(
-      path.resolve(__dirname, './index.js'),
+      path.resolve(import.meta.dirname, './index.js'),
       ['.test'],
       {
-        cwd: path.resolve(__dirname, '../'),
+        cwd: path.resolve(import.meta.dirname, '../'),
         stdio: 'pipe',
       },
     );

From c12bbe475443c7da5e7e017b3551320b5ec0b2fa Mon Sep 17 00:00:00 2001
From: gabriel miranda <gabrielmfern@outlook.com>
Date: Wed, 26 Nov 2025 15:32:37 -0300
Subject: [PATCH 08/10] try using shell without arguments

---
 packages/create-email/src/index.spec.ts                |  9 ++-------
 .../preview-server/scripts/build-preview-server.mts    | 10 ++--------
 packages/preview-server/scripts/dev.mts                | 10 ++--------
 3 files changed, 6 insertions(+), 23 deletions(-)

diff --git a/packages/create-email/src/index.spec.ts b/packages/create-email/src/index.spec.ts
index 4bd17c65f3..66df164f21 100644
--- a/packages/create-email/src/index.spec.ts
+++ b/packages/create-email/src/index.spec.ts
@@ -41,14 +41,9 @@ describe('automatic setup', () => {
   });
 
   test.sequential('type checking', { timeout: 10_000 }, async () => {
-    const tscBinary = path.resolve(
-      import.meta.dirname,
-      process.platform === 'win32'
-        ? '../node_modules/.bin/tsc.cmd'
-        : '../node_modules/.bin/tsc',
-    );
-    const typecheckingProcess = spawnSync(tscBinary, [], {
+    const typecheckingProcess = spawnSync('npx tsc', {
       cwd: starterPath,
+      shell: true,
       stdio: 'pipe',
     });
     if (typecheckingProcess.stderr) {
diff --git a/packages/preview-server/scripts/build-preview-server.mts b/packages/preview-server/scripts/build-preview-server.mts
index d11482903f..fde679aa76 100644
--- a/packages/preview-server/scripts/build-preview-server.mts
+++ b/packages/preview-server/scripts/build-preview-server.mts
@@ -2,15 +2,9 @@ import { spawn } from 'node:child_process';
 import fs from 'node:fs';
 import path from 'node:path';
 
-const nextBinaryPath = path.resolve(
-  import.meta.dirname,
-  process.platform === 'win32'
-    ? '../node_modules/.bin/next.cmd'
-    : '../node_modules/.bin/next',
-);
-
-const nextBuildProcess = spawn(nextBinaryPath, ['build'], {
+const nextBuildProcess = spawn('pnpm next build', {
   detached: true,
+  shell: true,
   stdio: 'inherit',
   cwd: path.resolve(import.meta.dirname, '../'),
 });
diff --git a/packages/preview-server/scripts/dev.mts b/packages/preview-server/scripts/dev.mts
index fb9942daac..dbb1bc095c 100644
--- a/packages/preview-server/scripts/dev.mts
+++ b/packages/preview-server/scripts/dev.mts
@@ -30,15 +30,9 @@ NEXT_PUBLIC_IS_PREVIEW_DEVELOPMENT=true`,
   'utf8',
 );
 
-const nextBinaryPath = path.resolve(
-  import.meta.dirname,
-  process.platform === 'win32'
-    ? '../node_modules/.bin/next.cmd'
-    : '../node_modules/.bin/next',
-);
-
-const webServerProcess = child_process.spawn(nextBinaryPath, ['dev'], {
+const webServerProcess = child_process.spawn('pnpm next dev', {
   cwd: previewServerRoot,
+  shell: true,
   stdio: 'inherit',
 });
 

From 0a4a3c997d7b5bc275404bb4ec2580e0697dfe93 Mon Sep 17 00:00:00 2001
From: gabriel miranda <gabrielmfern@outlook.com>
Date: Wed, 26 Nov 2025 15:39:17 -0300
Subject: [PATCH 09/10] add execPath for better windows support

---
 packages/create-email/src/index.spec.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/create-email/src/index.spec.ts b/packages/create-email/src/index.spec.ts
index 66df164f21..6282c76f74 100644
--- a/packages/create-email/src/index.spec.ts
+++ b/packages/create-email/src/index.spec.ts
@@ -11,8 +11,8 @@ describe('automatic setup', () => {
     }
 
     const createEmailProcess = spawnSync(
-      path.resolve(import.meta.dirname, './index.js'),
-      ['.test'],
+      process.execPath,
+      [path.resolve(import.meta.dirname, './index.js'), '.test'],
       {
         cwd: path.resolve(import.meta.dirname, '../'),
         stdio: 'pipe',

From 032309b998669563517db3f40698774e57db7822 Mon Sep 17 00:00:00 2001
From: gabriel miranda <gabrielmfern@outlook.com>
Date: Wed, 26 Nov 2025 16:55:14 -0300
Subject: [PATCH 10/10] fix tsconfig

---
 packages/create-email/tsconfig.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/create-email/tsconfig.json b/packages/create-email/tsconfig.json
index 663a8da103..8c1c2ea235 100644
--- a/packages/create-email/tsconfig.json
+++ b/packages/create-email/tsconfig.json
@@ -4,7 +4,7 @@
   "exclude": ["dist", "build", "node_modules", ".test"],
   "compilerOptions": {
     "moduleResolution": "nodenext",
-    "module": "node20",
+    "module": "nodenext",
     "noEmit": true,
     "types": ["vitest/globals"]
   }