Nginx reverse proxy patterns for Next.js and ASP.NET Core products

Even when the actual apps already expose HTTP servers, a reverse proxy still matters. Nginx gives you one place to handle host routing, TLS termination, upgrade headers for WebSockets, timeouts, and the forwarded headers the backend needs to log real client IPs correctly.

That is especially helpful when the product has a landing app, a client panel, and an API on separate internal ports but needs to look like one coherent platform externally.

The common mistakes are missing upgrade headers for realtime connections, missing forwarded headers, and wrong assumptions about which host or protocol the backend sees. Those small configuration gaps later turn into broken WebSockets, wrong IP logs, and incorrect redirect behavior.

When the proxy layer is wrong, the SEO product itself becomes harder to trust. Logged IPs can be incorrect, status endpoints may look healthy while WebSockets fail, and public report routes might resolve with inconsistent canonical behavior or mixed-origin assumptions.

The best production Nginx setup is the one operators can read quickly. Clear host-based routing, explicit proxy headers, and predictable timeouts are usually better than a very clever setup that only one person can reason about under pressure.