---
title: Upgrading Arc
editUrl: https://github.com/Cratis/Arc/edit/main/Documentation/upgrading/index.md
description: Changes in Arc that can need an action from you when you upgrade, and what to do about each one.
---


Most Arc upgrades need nothing from you. When a release changes a default or a behavior that an
application can rely on, it gets a page here. Each page answers the question that matters most first:
**does anything change for you?** It then names who is affected and the one change that keeps the
previous behavior when you need it.

| Change | What it means for you |
| --- | --- |
| [Secure defaults](/arc/upgrading/secure-defaults/) | Forwarded identity headers need an explicit opt-in before Arc trusts them, and discovery endpoints require authentication outside Development. |