Guide on getting Server Authority Test for testing your games with it

Hello,

On the RDC of 2025, Server Authority has been announced to be available for early testing, while that itself is cool, you would need to sign up, get selected and even sign a NDA.

Fortunately for everyone else, the server authority feature is in production builds of Studio and just needs to be enabled, while you won’t be directly able to provide feedback to Roblox about this, you will be atleast able to test your existing games or create new features integrating Server Authority.

:warning: Disclaimer: This guide requires you to patch (modify) the Studio build to get access to this feature, which inherently breaks Roblox TOS, while this may be a risk, no one was ever punished nor was this ever enforced on Roblox Studio.

The early test resides on the Roblox Studio v0.690.0.6900721, which wasn’t yet released but we can still download it using Roblox Studio Mod Manager

Once downloaded, you need to obtain something known as “internal permission” inside Roblox Studio, this is basically permission given to people who work at Roblox or have been granted it explicitly, for this we will be using Internal Studio Patcher

This tool will locate the code responsible for checking if you have this permission and trick Roblox Studio into thinking you have it.

Once properly patched, we still won’t have access to Server Authority, we need to override something known as FFlag, basically a feature flag, we need to override is few of them for all features, here is the list:

  1. DebugHashTableMetrics
  2. NextGenReplicatorEnabledRead3 - Seems to be already set to true
  3. DebugEnableAuroraService
  4. StudioAuroraEditorSupport

Once overrided, upon entering into any game you own, you will see this new option called “Authority Mode”, once you switch this to “Server” instead of “Automatic”, Server Authority will be active in your game (Keep in mind publishing this game to public won’t actually enable it)

For easier following of this guide, here is a video showcasing the steps:

20 Likes

You are amazing. I legitimately cannot put into words how much I appreciate you putting this knowledge out. My goat.

2 Likes

You need to enable more flags than that. At the bare minimum you also need NextGenReplicatorEnabledWrite4, DebugEnableAuroraService and DebugAuroraDefaultConfig enabled to start seeing the rollback system work.

I’m also fairly certain the current version included in the production build is outdated/incomplete. You need a special build to get everything to work properly, which no one to my knowledge has access to yet.

1 Like

Aurora service is enabled without overriding any of those, about rollbacks not sure, all I know this is pretty consistent to what they showcased in RDC 2025.

Roblox doesn’t have good history of actually making early testing features not included in production builds, so I think this is pretty up to date.

I did this reverse engineering (to enable Server Authority) myself and I think it’s crazy for roblox to force you into signing NDA over a feature that is publicly in the binary, plus I wanted to play with it for myself and I myself cannot sign NDAs so it would be pretty impossible to get the feature the “proper” way.

So I decided to share the knowledge for everyone else who also wants to try it.

No prediction is happening with just DebugHashTableMetrics. Character physics are only controlled through the legacy ‘no network ownership’ mode with no client predication or rollback, as you can tell by the input delay. There’s also supposed to be special scripts under ReplicatedStorage that use InputActionSystem for input recording.

You have to sign an NDA for the Early Features Program? Where are you getting this information?

Not true, I managed to enable it myself with SetPredictionMode (Instance | Roblox API Reference), again not sure about rollbacks.

Here Launching Early Access Programs: Test Experimental Features - #30 by Wh7sk

The Server Authority system as a whole needs multiple FFlags to be fully enabled without any issues.
The FFlag you enabled only allows you to enable a very limited portion of the behavior that comes with Server Authority. Next Gen Replicator and other flags must be enabled to have client prediction, rollback, and input recording.

The API you mentioned have also only been added in v690. (Released yesterday, will roll out today.)
And it can only be used when all of the prediction related fast flags have been enabled.

No official sources from Roblox has mentioned early-access-programs putting you under an NDA. There’s no explicit mention of it found anywhere. I wouldn’t trust a random person’s statement about it. Feel free to correct me however, if there’s any official mention of it.

If you know about FFlags that need to be overridden for more of the server authority features, please share them.

https://devforum.roblox.com/t/early-server-authority-access/3630543/52?u=tenebrisnoctua

Everything but NextGenReplicatorEnabledWrite4 and DebugAuroraDefaultConfig seems to be there, but I will edit this guide then.

I seem to not have the Internal version of roblox studio after messing with something. Do you know how to fix?
image

Edit: if anyone has this issue just go into the Studio Settings and search “Internal”

1 Like

I’m late, but remember to exercise extreme caution using this feature early, as this API is unstable and likely will break before it reaches production.

It’s dangerous to use this in a DataModel you intend to save to production, because it might get corrupted. Only use this for experimental work with the expectation it will break.

2 Likes

Small question about server authority: do you know about the fact that if you move your character on your side it will take a small delay for the server to get that information and move your character for everyone else? what happens when server authority come’s out and when you press W to move your character there is a very small delay for when your character actually move’s but with the client side movement it does it instantly?

Example here with small delays with character movement: https://www.youtube.com/watch?v=VGulLY1Agg8

This is what client-side prediction system aims to solve. Server Authority on its own does not provide smooth movement.

That video displays the behavior of server authority in a very early experimental state.
There’s a new and better character controlling system with the FixedHeartbeat event.

Besides that, this system is still very much a work-in-progress. Do not create systems expecting to use in production. Especially if you’re enrolled in the early-access, you will not be able to use the Roblox Client.

1 Like