From f9faea18518379f80ee0487888609b00c8e16ff8 Mon Sep 17 00:00:00 2001
From: Jeff Emmett <jeff@jeffemmett.com>
Date: Wed, 18 Feb 2026 23:34:04 +0000
Subject: [PATCH] fix: connect frontend to sync server for multiplayer
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NEXT_PUBLIC_SYNC_URL was never set, so useRoom always fell into
local-only mode — users couldn't see other joiners. Added build arg
to bake wss://sync.rmaps.online into the client bundle.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 Dockerfile         | 3 +++
 docker-compose.yml | 2 ++
 2 files changed, 5 insertions(+)

diff --git a/Dockerfile b/Dockerfile
index 52acc98..1b0d4ca 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -23,6 +23,9 @@ COPY rmaps-online/ .
 
 ENV NEXT_TELEMETRY_DISABLED=1
 ENV NODE_ENV=production
+# Sync server URL baked into client bundle at build time
+ARG NEXT_PUBLIC_SYNC_URL
+ENV NEXT_PUBLIC_SYNC_URL=${NEXT_PUBLIC_SYNC_URL}
 
 RUN npm run build
 
diff --git a/docker-compose.yml b/docker-compose.yml
index 6c26880..c0868f1 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -5,6 +5,8 @@ services:
     build:
       context: ..
       dockerfile: rmaps-online/Dockerfile
+      args:
+        - NEXT_PUBLIC_SYNC_URL=wss://sync.rmaps.online
     container_name: rmaps-online
     restart: unless-stopped
     environment: