diff --git a/.env.example b/.env.example
new file mode 100644
index 0000000..04480ff
--- /dev/null
+++ b/.env.example
@@ -0,0 +1,2 @@
+CODESERVER_HOST=your-codeserver.example.com
+CODESERVER_PORT=3000
diff --git a/.gitignore b/.gitignore
index 4f076b5..17e8407 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,6 @@
 node_modules/
 .next/
 out/
+.env.local
+.env*.local
+tsconfig.tsbuildinfo
diff --git a/next-env.d.ts b/next-env.d.ts
index 9edff1c..c4b7818 100644
--- a/next-env.d.ts
+++ b/next-env.d.ts
@@ -1,6 +1,6 @@
 /// <reference types="next" />
 /// <reference types="next/image-types/global" />
-import "./.next/types/routes.d.ts";
+import "./.next/dev/types/routes.d.ts";
 
 // NOTE: This file should not be edited
 // see https://nextjs.org/docs/app/api-reference/config/typescript for more information.
diff --git a/next.config.ts b/next.config.ts
index 1040bca..2462dd4 100644
--- a/next.config.ts
+++ b/next.config.ts
@@ -1,10 +1,32 @@
 import type { NextConfig } from "next";
 
 const isProd = process.env.NODE_ENV === "production";
+const isCodeserver = process.env.NEXT_DEV_PROFILE === "codeserver";
+
+// In dev under code-server's reverse proxy, basePath/assetPrefix must match
+// the proxy URL so links, assets, and the HMR socket all resolve.
+// Use /absproxy/{port} (NOT /proxy/{port}) — /proxy strips the prefix before
+// forwarding; /absproxy preserves it so basePath matches the incoming request.
+// CODESERVER_HOST and CODESERVER_PORT are loaded from .env.local by Next.
+function codeserverConfig() {
+  const host = process.env.CODESERVER_HOST;
+  if (!host) {
+    throw new Error(
+      "CODESERVER_HOST is required when NEXT_DEV_PROFILE=codeserver (set it in .env.local)"
+    );
+  }
+  const port = process.env.CODESERVER_PORT ?? "3000";
+  return { basePath: `/absproxy/${port}`, allowedDevOrigins: [host] };
+}
+
+const cs = isCodeserver ? codeserverConfig() : null;
+const basePath = cs?.basePath ?? (isProd ? "/loto" : "");
 
 const nextConfig: NextConfig = {
   output: "export",
-  basePath: isProd ? "/loto" : "",
+  basePath,
+  assetPrefix: basePath || undefined,
+  ...(cs?.allowedDevOrigins ? { allowedDevOrigins: cs.allowedDevOrigins } : {}),
 };
 
 export default nextConfig;
diff --git a/package.json b/package.json
index 92b9a4b..65e8ec7 100644
--- a/package.json
+++ b/package.json
@@ -4,6 +4,7 @@
   "private": true,
   "scripts": {
     "dev": "next dev",
+    "dev:codeserver": "NEXT_DEV_PROFILE=codeserver next dev -H 0.0.0.0",
     "build": "next build",
     "start": "next start",
     "lint": "eslint"