From a7422b79b22d58779e0319f8808d2e184cc5e5ef Mon Sep 17 00:00:00 2001
From: Mark Dalgleish <mark.john.dalgleish@gmail.com>
Date: Mon, 8 May 2023 10:12:27 +1000
Subject: [PATCH] fix(dev): disable Vanilla Extract if not installed

---
 .changeset/slimy-snakes-do.md                         | 5 +++++
 packages/remix-dev/compiler/plugins/vanillaExtract.ts | 7 +++++++
 2 files changed, 12 insertions(+)
 create mode 100644 .changeset/slimy-snakes-do.md

diff --git a/.changeset/slimy-snakes-do.md b/.changeset/slimy-snakes-do.md
new file mode 100644
index 00000000000..2dff196c56d
--- /dev/null
+++ b/.changeset/slimy-snakes-do.md
@@ -0,0 +1,5 @@
+---
+"@remix-run/dev": patch
+---
+
+Only process .css.ts/js files with Vanilla Extract if `@vanilla-extract/css` is installed
diff --git a/packages/remix-dev/compiler/plugins/vanillaExtract.ts b/packages/remix-dev/compiler/plugins/vanillaExtract.ts
index 2754a2b0fcd..e7501a760aa 100644
--- a/packages/remix-dev/compiler/plugins/vanillaExtract.ts
+++ b/packages/remix-dev/compiler/plugins/vanillaExtract.ts
@@ -60,6 +60,13 @@ export function vanillaExtractPlugin(
   return {
     name: pluginName,
     async setup(build) {
+      try {
+        require.resolve("@vanilla-extract/css");
+      } catch (_) {
+        // If Vanilla Extract isn't installed, skip this plugin.
+        return;
+      }
+
       let root = config.appDirectory;
 
       let postcssProcessor = await getPostcssProcessor({