diff --git a/.changeset/vite-9-environment-hooks.md b/.changeset/vite-9-environment-hooks.md
new file mode 100644
index 0000000..c434fcd
--- /dev/null
+++ b/.changeset/vite-9-environment-hooks.md
@@ -0,0 +1,5 @@
+---
+'@solidjs/vite-plugin': patch
+---
+
+Add Vite 9 forward compatibility by using the per-environment consumer in plugin hooks and accepting Vite 9 as a peer.
diff --git a/examples/vite-8/vite.config.ts b/examples/vite-8/vite.config.ts
index f612fbe..b91b775 100644
--- a/examples/vite-8/vite.config.ts
+++ b/examples/vite-8/vite.config.ts
@@ -2,6 +2,9 @@ import { defineConfig } from 'vite';
 import solidPlugin from '@solidjs/vite-plugin';
 
 export default defineConfig({
+  future: {
+    removePluginHookSsrArgument: 'warn',
+  },
   plugins: [
     {
       name: 'simulate-eliminated-lazy-importer',
diff --git a/package.json b/package.json
index 5ba4ce8..b7ab1b3 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@solidjs/vite-plugin",
   "version": "3.0.0-next.30",
-  "description": "solid-js integration plugin for vite 6/7/8",
+  "description": "solid-js integration plugin for Vite",
   "type": "module",
   "files": [
     "dist",
@@ -88,7 +88,7 @@
     "@solidjs/web": "^2.0.0-rc.0",
     "@testing-library/jest-dom": "^5.16.6 || ^5.17.0 || ^6.*",
     "solid-js": "^2.0.0-rc.0",
-    "vite": "^6.0.0 || ^7.0.0 || ^8.0.0"
+    "vite": "^6.0.0 || ^7.0.0 || ^8.0.0 || ^9.0.0"
   },
   "peerDependenciesMeta": {
     "@testing-library/jest-dom": {
diff --git a/scripts/test-examples.ts b/scripts/test-examples.ts
index 235c0df..5718a99 100644
--- a/scripts/test-examples.ts
+++ b/scripts/test-examples.ts
@@ -3,6 +3,8 @@ import { promisify } from 'node:util';
 
 const execAsync = promisify(exec);
 const examples = ['vite-6', 'vite-7', 'vite-8'];
+const pluginHookSsrDeprecation =
+  "Plugin hook `options.ssr` is replaced with `this.environment.config.consumer === 'server'`.";
 const PORT = 4173;
 const TEST_TIMEOUT = 5 * 60 * 1000; // 5 minutes
 const cypressEnv = { ...process.env, ELECTRON_RUN_AS_NODE: undefined };
@@ -29,7 +31,10 @@ async function runExample(example) {
   try {
     // Install and build
     await execAsync('pnpm install', { cwd: examplePath });
-    await execAsync('pnpm run build', { cwd: examplePath });
+    const { stdout, stderr } = await execAsync('pnpm run build', { cwd: examplePath });
+    if (`${stdout}\n${stderr}`.includes(pluginHookSsrDeprecation)) {
+      throw new Error(`Vite's deprecated plugin hook SSR argument was used in ${example}`);
+    }
 
     // Start preview server with timeout
     const server = spawn('pnpm', ['run', 'preview'], { cwd: examplePath });
diff --git a/src/environment.ts b/src/environment.ts
index 3fe0d12..392b2d9 100644
--- a/src/environment.ts
+++ b/src/environment.ts
@@ -13,3 +13,13 @@
 export function isRunnableEnvironment(environment: unknown): boolean {
   return !!environment && typeof environment === 'object' && 'runner' in environment;
 }
+
+export function getEnvironmentConsumer(
+  environment: unknown,
+  options?: { ssr?: boolean },
+): 'client' | 'server' {
+  const consumer = (environment as { config?: { consumer?: string } } | undefined)?.config
+    ?.consumer;
+  if (consumer === 'client' || consumer === 'server') return consumer;
+  return options?.ssr ? 'server' : 'client';
+}
diff --git a/src/index.ts b/src/index.ts
index f031ba8..88818a4 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -26,7 +26,7 @@ export type { StartOptions };
 import path from 'path';
 import type { FilterPattern, Plugin, ViteDevServer } from 'vite';
 import { createFilter, version } from 'vite';
-import { isRunnableEnvironment } from './environment.js';
+import { getEnvironmentConsumer, isRunnableEnvironment } from './environment.js';
 import { crawlFrameworkPkgs } from 'vitefu';
 
 const require = createRequire(import.meta.url);
@@ -993,7 +993,7 @@ export default function solidPlugin(options: Partial<Options> = {}): Plugin[] {
     },
 
     async transform(source, id, transformOptions) {
-      const isSsr = transformOptions && transformOptions.ssr;
+      const isSsr = getEnvironmentConsumer(this.environment, transformOptions) === 'server';
       const currentFileExtension = getExtension(id);
 
       const extensionsToWatch = options.extensions || [];
diff --git a/src/server-functions/index.ts b/src/server-functions/index.ts
index 61346dd..836a486 100644
--- a/src/server-functions/index.ts
+++ b/src/server-functions/index.ts
@@ -17,7 +17,7 @@ import {
   type Plugin,
   type ViteDevServer,
 } from 'vite';
-import { isRunnableEnvironment } from '../environment.js';
+import { getEnvironmentConsumer, isRunnableEnvironment } from '../environment.js';
 import { joinBase, sendWebResponse, webRequestFromNode } from '../http.js';
 import { compile, type CompileOptions } from './compile.js';
 import xxHash32 from './xxhash32.js';
@@ -487,7 +487,7 @@ export function serverFunctions(
       enforce: 'pre',
       resolveId(source, _importer, opts) {
         if (source === HANDLER_ID) {
-          if (!opts?.ssr) {
+          if (getEnvironmentConsumer(this.environment, opts) !== 'server') {
             this.error(
               `${HANDLER_ID} is server-only; import it from your server entry (SSR build).`,
             );
@@ -497,7 +497,7 @@ export function serverFunctions(
         return null;
       },
       load(id, opts) {
-        if (id === HANDLER_ID && opts?.ssr) {
+        if (id === HANDLER_ID && getEnvironmentConsumer(this.environment, opts) === 'server') {
           const externalDev =
             this.environment.mode === 'dev' &&
             (internal.externalDevServer || !isRunnableEnvironment(this.environment));
@@ -633,7 +633,7 @@ export function serverFunctions(
         return null;
       },
       async load(id, opts) {
-        const mode = opts?.ssr ? 'server' : 'client';
+        const mode = getEnvironmentConsumer(this.environment, opts);
         if (id === manifestId) {
           if (isBuild && mode === 'server') {
             // Merge the client build's persisted discoveries at load time,
@@ -659,7 +659,7 @@ export function serverFunctions(
       name: 'solid:server-functions/compiler',
       enforce: 'pre',
       async transform(code, fileId, opts) {
-        const mode = opts?.ssr ? 'server' : 'client';
+        const mode = getEnvironmentConsumer(this.environment, opts);
         const [id] = fileId.split('?');
         if (!filter(id)) {
           return null;
diff --git a/src/ssr/index.ts b/src/ssr/index.ts
index ec9e4af..3154715 100644
--- a/src/ssr/index.ts
+++ b/src/ssr/index.ts
@@ -51,7 +51,7 @@ import {
   type PreviewServer,
   type ViteDevServer,
 } from 'vite';
-import { isRunnableEnvironment } from '../environment.js';
+import { getEnvironmentConsumer, isRunnableEnvironment } from '../environment.js';
 import {
   collectDevStyles,
   collectDevStyleSources,
@@ -1035,8 +1035,9 @@ export function startServe(
         return null;
       },
       async load(id, opts) {
+        const consumer = getEnvironmentConsumer(this.environment, opts);
         if (id === HANDLER_ID) {
-          if (!opts?.ssr) {
+          if (consumer !== 'server') {
             this.error(`${HANDLER_ID} is server-only; import it from server code (SSR build).`);
           }
           const externalDev =
@@ -1046,7 +1047,7 @@ export function startServe(
           return handlerModuleCode(externalDev);
         }
         if (id === RESOLVED_DEV_STYLES_ID) {
-          if (!opts?.ssr || this.environment.mode !== 'dev') {
+          if (consumer !== 'server' || this.environment.mode !== 'dev') {
             this.error(`${DEV_STYLES_ID} is only available to the development server handler.`);
           }
           return devStylesModuleCode(this.environment, (file) => this.addWatchFile(file));