UNREAL ENGINE SDK
Xsolla SDK 3 for Unreal Engine: Early Access Pilot
Xsolla SDK 3 for Unreal Engine is in early access. It handles the commercial layer of your game: signing players in, showing them your catalog, taking their money, and delivering what they bought. This page covers what the pilot is, what we are asking of you, and where to start.
Sign-in works through an Xsolla account, Steam, or EOS, with full Blueprint support throughout.
Join the pilot programWhat the pilot is
SDK 3 for Unreal is complete through its MVP feature set and is in internal verification. It has been tested against first-party standards, but a test suite only proves the paths we thought to write. Real games bring permutations we did not anticipate: different engine versions, unusual sign-in and inventory setups, partial scopes, and design decisions we would never have made ourselves.
If you have an Unreal project on hand, or you are starting one, integrate SDK 3 and put it through its paces. Every project runs a slightly different setup, so each one shows us something the last did not.
Partial scope is welcome. A title that only exercises Steam sign-in is still a valuable pilot. Run the gates your project supports and file a report.
The four capability gates
A gate is one part of the SDK working end to end in a real game. There are four, and each has a walkthrough in the repo.
| Gate | What it proves |
|---|---|
| C1 Auth | A player logs in, closes and reopens the game, and is still signed in |
| C2 Catalog Sync | Your in-game storefront renders your catalog: items and currencies |
| C3 Purchase | Checkout launches from inside Unreal for a catalog item |
| C4 Finalize | The order reaches a final state and the item appears in the player's inventory |
Install is a prerequisite. C1 starts once your project compiles.
Players can sign in three ways: with an Xsolla account, through Steam, or through EOS. We want all three proven in a live game, and we need at least one project covering each. After that, the more the better.
What SDK 3 gives you
However a player signs in, the purchase code you write is the same. Steam and EOS hand over an authentication ticket that resolves into a single Xsolla session, and everything downstream of that is identical.
The core is structurally 1:1 with the Unity 3.x SDK, with each Unity package assembly mapping to an Unreal plugin module. If your studio ships on both engines, the mental model transfers.
Pure code, minimal dependencies, with an online-subsystem dependency only in the IAP module. The test suite ships alongside the SDK as a companion plugin and runs against Valve's and Epic's own sample projects.
The SDK coexists with Steam or EOS while holding the Xsolla session for commerce. Steam Wallet and EOS Ecom work as real IAP backends behind a common interface, with per-provider pricing.
A player who launches from Xsolla Launcher arrives already signed in. Call LoginWithLauncherToken and the SDK uses the session token as-is.
Every capability the SDK exposes is reachable from Blueprint, not just C++.
Platforms and distribution
Windows (Win64) is the primary development host, with full platform dispatch, all Pay Station web-view paths, a sandbox and production runtime toggle, and locale resolution. Linux is supported alongside it, including dedicated-server builds. macOS, iOS, and Android are next-milestone scope.
Distribution is source-only. There is no prebuilt binary and no Fab listing. Your project's own Unreal build compiles the plugin, which keeps packages platform-neutral and version-neutral.
Where to start
Setup guides — the documentation index, architecture overview, installation steps, and the Steam/EOS integration walkthroughs — live in the pilot repo. Access to the repo and code is granted by joining the pilot program below.
Reporting
File a GitHub issue with the pilot-ready label, or bring it to the pilot Discord. Either one reaches the SDK team inside the pilot window.
Blunt, critical feedback is welcome.
One thing worth knowing up front: parts of the repo still carry leftover planning and tracking content from development, and some of it has yet to see human eyes. If you hit duplicated docs, stale plans, or orphaned content, flag that too.