The Vite point is the one that bites quietly. Without server.strictPort it just moves to 5174, and the only symptom is an OAuth callback or CORS error that looks unrelated. Setting strictPort: true in shared repos turns that into a loud failure, which is easier to debug. Binding databases to 127.0.0.1 is also a good default even when there's no clash, since nothing outside the machine needs to reach a dev Postgres.