Does Crux have a native Unreal Engine SDK?

Yes, as a beta C++ plugin. Its protocol and structure tests pass, but it has not yet been compiled with Unreal Build Tool against the engine. Raw REST/OpenAPI through FHttpModule remains the verified fallback while the plugin completes engine validation.

Does Crux replace Unreal replication or Epic Online Services?

No. Unreal replication and online-service integrations solve realtime/platform jobs. Crux is a persistent backend for auth, durable player data, stats, leaderboards, economy, live config and server registry.

Does Crux host Unreal dedicated servers?

No. Crux does not currently provide general Unreal dedicated-server fleet hosting. Run the Unreal server with the hosting or orchestration provider you choose and call Crux over HTTPS for persistent backend operations.

Unreal Engine · beta C++ SDK + REST

Keep Unreal authoritative. Put persistent state behind a plain HTTP contract.

Unreal already owns replication, RPCs and game simulation. Crux handles the data that must survive the match: player identity, saves, stats, achievements, leaderboards, economy, live config and server registry. Use the beta C++ plugin for the typed client surface, or call the same HTTPS/OpenAPI contract directly with FHttpModule.

Create a free Unreal backend → See the UE dedicated-server path

SDK status: beta. The plugin is protocol/structure-tested but has not yet been compiled with UBT against Unreal Engine. REST/OpenAPI remains the verified fallback. Crux does not host your UE fleet.

First external call FHttpModule

POST /v1/auth/anonymous
Authorization: ApiKey pk_...
Content-Type: application/json



// Unreal: FHttpModule::Get()
//        .CreateRequest()

Verify before you integrate

The Unreal plugin is real, but still beta.

Inspect the beta C++ plugin and the public OpenAPI contract. The plugin has protocol/structure coverage, but its engine-facing code still needs a real UBT build before production use.

Live API status

A live check of the hosted API right now. No made-up uptime percentage and no hidden demo environment.

Check current status

Public API contract

The hosted HTTP surface is documented as OpenAPI. Inspect the wire format before choosing an SDK or writing an adapter.

Open the spec

MIT client SDKs

The JavaScript, Godot, Unity, and Roblox client SDK source is public. The hosted backend itself remains a managed proprietary service.

Inspect the SDK source

Documented exit path

Read what is exportable today and the written commitment for advance notice plus an export window if the hosted service winds down.

Read the exit guarantee

Epic HTTP API reference

Unreal exposes FHttpModule and IHttpRequest for ordinary HTTP integration. That remains the verified fallback while Crux's beta C++ plugin completes engine validation.

Open Epic's HTTP docs

Layer boundary

Unreal owns the frame. The backend owns what must survive it.

Keep in Unreal / platform services

Authoritative gameplay simulation and replication
Actor state, RPCs and movement/network prediction
Online Subsystem / Online Services integrations that fit your platforms
EOS/Steam/console functionality you intentionally keep

Put in Crux

Guest/email player auth and persistent player records
Cloud saves, stats, achievements and inventories
Leaderboards and economy outside one server process
Backend-owned live config
Dedicated-server registration and heartbeat data

First-success path

Choose the beta plugin or prove the wire contract with FHttpModule.

The beta plugin already wraps the Crux API, but its first real Unreal build is still part of the work. If you want the lowest-risk proof today, make the anonymous-login POST with FHttpModule first; that verifies DNS/TLS, authorization and the wire contract from the actual Unreal process.

Create the free project and run the dashboard sample.
Either copy the Crux/ beta plugin into Plugins/, or start with the generated FHttpModule request.
Run it from Unreal; Crux marks the first external credential use as the real activation event.
Parse the player token and add only the persistent endpoints you need.
For a trusted dedicated server, switch privileged operations to a server token rather than embedding secrets in the client.

Open the Unreal SDK path → Inspect OpenAPI

Unreal decision paths

Your question	Start here
UE dedicated server + persistent backend	Dedicated-server integration
Server authority / anti-cheat boundary	Server-authoritative validation
EOS vs application backend	EOS vs custom backend
Fleet orchestration choices	Orchestration guide
Beta C++ SDK	Unreal SDK quickstart
Wire contract / fallback	Crux OpenAPI

Hosting boundary

Crux is not your Unreal fleet manager.

Epic's dedicated-server model is headless and authoritative, but where that executable runs is a separate infrastructure choice. Crux currently provides the persistent/backend API and server registry, not general Unreal process hosting or orchestration. Keep the hosting adapter separate so you can change it without moving player data.

Start at the boundary

Test the Unreal plugin, or the HTTP contract, before moving state.

The beta plugin gives you a first-party C++ surface; FHttpModule gives you the lowest-level fallback. Either path should prove a live call before production state moves.

Create the free Unreal project →