diff --git a/packages/astro/src/vite-plugin-fetch/index.ts b/packages/astro/src/vite-plugin-fetch/index.ts
index 5191c1b80..8363248a7 100644
--- a/packages/astro/src/vite-plugin-fetch/index.ts
+++ b/packages/astro/src/vite-plugin-fetch/index.ts
@@ -3,20 +3,6 @@ import type { BaseNode, Identifier } from 'estree';
 import MagicString from 'magic-string';
 import { walk } from 'estree-walker';
 
-// https://github.com/vitejs/vite/discussions/5109#discussioncomment-1450726
-function isSSR(options: undefined | boolean | { ssr?: boolean }): boolean {
-  if (options === undefined) {
-    return false;
-  }
-  if (typeof options === 'boolean') {
-    return options;
-  }
-  if (typeof options == 'object') {
-    return !!options.ssr;
-  }
-  return false;
-}
-
 // This matches any JS-like file (that we know of)
 // See https://regex101.com/r/Cgofir/1
 const SUPPORTED_FILES = /\.(astro|svelte|vue|[cm]?js|jsx|[cm]?ts|tsx)$/;
@@ -28,23 +14,23 @@ function isIdentifier(node: BaseNode): node is Identifier {
 }
 
 export default function pluginFetch(): Plugin {
-	return {
-		name: '@astrojs/vite-plugin-fetch',
-		enforce: 'post',
-		async transform(code, id, opts) {
-			const ssr = isSSR(opts);
-			// If this isn't an SSR pass, `fetch` will already be available!
-			if (!ssr) {
-				return null;
-			}
-			// Only transform JS-like files
-			if (!id.match(SUPPORTED_FILES)) {
-				return null;
-			}
-			// Optimization: only run on probable matches
-			if (!code.includes('fetch')) {
-				return null;
-			}
+  return {
+    name: '@astrojs/vite-plugin-fetch',
+    enforce: 'post',
+    async transform(code, id, opts) {
+      const ssr = Boolean(opts?.ssr);
+      // If this isn't an SSR pass, `fetch` will already be available!
+      if (!ssr) {
+        return null;
+      }
+      // Only transform JS-like files
+      if (!id.match(SUPPORTED_FILES)) {
+        return null;
+      }
+      // Optimization: only run on probable matches
+      if (!code.includes('fetch')) {
+        return null;
+      }
 
 			const ast = this.parse(code);
 			let fetchDeclared = false;
diff --git a/packages/astro/src/vite-plugin-jsx/index.ts b/packages/astro/src/vite-plugin-jsx/index.ts
index a1efb6ffd..8434aebb9 100644
--- a/packages/astro/src/vite-plugin-jsx/index.ts
+++ b/packages/astro/src/vite-plugin-jsx/index.ts
@@ -24,21 +24,6 @@ const IMPORT_STATEMENTS: Record<string, string> = {
 // be careful about esbuild not treating h, React, Fragment, etc. as unused.
 const PREVENT_UNUSED_IMPORTS = ';;(React,Fragment,h);';
 
-// This check on a flexible "options" object is needed because Vite uses this flexible argument for ssr.
-// More context: https://github.com/vitejs/vite/discussions/5109#discussioncomment-1450726
-function isSSR(options: undefined | boolean | { ssr: boolean }): boolean {
-	if (options === undefined) {
-		return false;
-	}
-	if (typeof options === 'boolean') {
-		return options;
-	}
-	if (typeof options == 'object') {
-		return !!options.ssr;
-	}
-	return false;
-}
-
 function getEsbuildLoader(fileExt: string): string {
 	return fileExt.substr(1);
 }