From 41c4139611ff4847af7cb6246b514c3ebaa4ab87 Mon Sep 17 00:00:00 2001
From: Ruben Carvalho <rcarvalho@adobe.com>
Date: Mon, 11 May 2026 14:53:36 +0200
Subject: [PATCH 1/2] fix(build): replace process.env.NODE_ENV at esbuild time

Adds process.env.NODE_ENV to the esbuild define config so built .js and
.dev.js files never contain raw process.env references. This fixes
ReferenceError: process is not defined for downstream consumers that load
SWC packages in a browser without a bundler (e.g. Sass playground), while
keeping dev/prod behaviour correct in built output.
---
 1st-gen/scripts/ts-tools.js | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/1st-gen/scripts/ts-tools.js b/1st-gen/scripts/ts-tools.js
index bb968b9853d..c86a27c8795 100644
--- a/1st-gen/scripts/ts-tools.js
+++ b/1st-gen/scripts/ts-tools.js
@@ -83,7 +83,10 @@ export const buildPackage = async (paths) => {
       build({
         ...config,
         entryPoints: devPaths,
-        define: { 'window.__swc.DEBUG': 'true' },
+        define: {
+          'window.__swc.DEBUG': 'true',
+          'process.env.NODE_ENV': '"development"',
+        },
         outExtension: { '.js': '.dev.js' },
         plugins: devPlugins,
       }).catch(() => process.exit(1))
@@ -91,7 +94,10 @@ export const buildPackage = async (paths) => {
   }
   const prodConfig = {
     ...config,
-    define: { 'window.__swc.DEBUG': 'false' },
+    define: {
+      'window.__swc.DEBUG': 'false',
+      'process.env.NODE_ENV': '"production"',
+    },
     plugins: paths.length === 1 ? [] : prodPlugins,
   };
   if (prodPath.length) {

From 89e88beb0c022bb946cd3a45416efa54e6122a09 Mon Sep 17 00:00:00 2001
From: Ruben Carvalho <rcarvalho@adobe.com>
Date: Mon, 11 May 2026 19:35:19 +0200
Subject: [PATCH 2/2] fix(2nd-gen): replace process.env.NODE_ENV in Vite
 library builds

Vite's library mode does not auto-replace process.env.NODE_ENV, so 2nd-gen
dist files contained raw process.env.NODE_ENV references. This caused
ReferenceError: process is not defined for downstream consumers that load
SWC packages in a browser without a bundler (e.g. Sass playground).

Adds a mode-aware define so dist files contain the literal mode value
('production' or 'development') instead of the runtime expression.
---
 2nd-gen/packages/core/vite.config.js | 9 +++++++--
 2nd-gen/packages/swc/vite.config.ts  | 9 +++++++--
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/2nd-gen/packages/core/vite.config.js b/2nd-gen/packages/core/vite.config.js
index f91fd99b164..9e08614ceda 100644
--- a/2nd-gen/packages/core/vite.config.js
+++ b/2nd-gen/packages/core/vite.config.js
@@ -86,7 +86,12 @@ function getEntries() {
   return entries;
 }
 
-export default defineConfig({
+export default defineConfig(({ mode }) => ({
+  define: {
+    'process.env.NODE_ENV': JSON.stringify(
+      mode === 'development' ? 'development' : 'production'
+    ),
+  },
   plugins: [
     dts({
       include: ['**/*.ts'],
@@ -125,4 +130,4 @@ export default defineConfig({
   esbuild: {
     target: 'es2018',
   },
-});
+}));
diff --git a/2nd-gen/packages/swc/vite.config.ts b/2nd-gen/packages/swc/vite.config.ts
index fd0ad4ba2c2..94e0d57d423 100644
--- a/2nd-gen/packages/swc/vite.config.ts
+++ b/2nd-gen/packages/swc/vite.config.ts
@@ -60,7 +60,12 @@ function processStylesheets(): Plugin {
   };
 }
 
-export default defineConfig({
+export default defineConfig(({ mode }) => ({
+  define: {
+    'process.env.NODE_ENV': JSON.stringify(
+      mode === 'development' ? 'development' : 'production'
+    ),
+  },
   plugins: [
     litCss({ exclude: ['./stylesheets/**/*.css'] }),
     processStylesheets(),
@@ -147,4 +152,4 @@ export default defineConfig({
   esbuild: {
     target: 'es2018',
   },
-});
+}));