From 9b2737ef774c14ba11df7800dfeba9c0cc7e6516 Mon Sep 17 00:00:00 2001
From: Ryan Malloy <ryan@supported.systems>
Date: Fri, 13 Feb 2026 03:45:23 -0700
Subject: [PATCH] Set PUBLIC_API_URL at build time for production

Vite inlines import.meta.env.PUBLIC_* at build time, not runtime.
Without this, the frontend falls back to localhost:8099 which doesn't
exist from the browser. Empty string means same-origin requests,
letting Caddy route /api/* to the backend.
---
 frontend/Dockerfile | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/frontend/Dockerfile b/frontend/Dockerfile
index ed39f80..a5cbc29 100644
--- a/frontend/Dockerfile
+++ b/frontend/Dockerfile
@@ -24,6 +24,12 @@ RUN npm ci
 COPY . .
 
 ENV ASTRO_TELEMETRY_DISABLED=1
+
+# PUBLIC_API_URL must be set at build time for Vite to inline it.
+# Empty string = same-origin (Caddy routes /api/* to backend).
+ARG PUBLIC_API_URL=""
+ENV PUBLIC_API_URL=${PUBLIC_API_URL}
+
 RUN npm run build