diff --git a/src/emulator/src/main.js b/src/emulator/src/main.js
index 67f2daf55..8a0492994 100644
--- a/src/emulator/src/main.js
+++ b/src/emulator/src/main.js
@@ -110,6 +110,23 @@ puter.ui.on('connection', event => {
 
 window.onload = async function()
 {
+    let emu_config; try {
+        emu_config = await puter.fs.read('config.json');
+    } catch (e) {}
+
+    if ( ! emu_config ) {
+        await puter.fs.write('config.json', JSON.stringify({}));
+        emu_config = {};
+    }
+
+    if ( emu_config instanceof Blob ) {
+        emu_config = await emu_config.text();
+    }
+
+    if ( typeof emu_config === 'string' ) {
+        emu_config = JSON.parse(emu_config);
+    }
+
     const resp = await fetch(
         './image/build/rootfs.bin'
     );
@@ -152,10 +169,14 @@ window.onload = async function()
         // bzimage_initrd_from_filesystem: true,
         autostart: true,
 
-        network_relay_url: "wisp://127.0.0.1:3000",
+        network_relay_url: emu_config.network_relay ?? "wisp://127.0.0.1:3000",
         virtio_console: true,
     });
 
+    emulator.add_listener('download-error', function(e) {
+        status.missing_files || (status.missing_files = []);
+        status.missing_files.push(e.file_name);
+    });
     
     const decoder = new TextDecoder();
     const byteStream = NewCallbackByteStream();
diff --git a/src/phoenix/src/puter-shell/providers/EmuCommandProvider.js b/src/phoenix/src/puter-shell/providers/EmuCommandProvider.js
index 81f90cea3..3c2257c2a 100644
--- a/src/phoenix/src/puter-shell/providers/EmuCommandProvider.js
+++ b/src/phoenix/src/puter-shell/providers/EmuCommandProvider.js
@@ -36,6 +36,19 @@ export class EmuCommandProvider {
         if ( conn.response.status.ready ) {
             p_ready.resolve();
         }
+        console.log('status from emu', conn.response);
+        if ( conn.response.status.missing_files ) {
+            const pfx = '\x1B[31;1m┃\x1B[0m ';
+            ctx.externs.out.write('\n');
+            ctx.externs.out.write('\x1B[31;1m┃ Emulator is missing files:\x1B[0m\n');
+            for (const file of conn.response.status.missing_files) {
+                ctx.externs.out.write(pfx+`-  ${file}\n`);
+            }
+            ctx.externs.out.write(pfx+'\n');
+            ctx.externs.out.write(pfx+'\x1B[33;1mDid you run `./tools/build_v86.sh`?\x1B[0m\n');
+            ctx.externs.out.write('\n');
+            return;
+        }
         console.log('awaiting emulator ready');
         ctx.externs.out.write('Waiting for emulator...\n');
         await p_ready;