That's according to a blog post on the game engine's website, in which it says it has changed its Terms of Service once more saying that developers can use whatever third-party tech they want with Unity.
However, the firm says that some services will be supported while others are not. This means that studios can use any tech they fancy, but the performance might not always be perfect as Unity says it won't fully understand what unsupported tech is up to.
This also means that Improbable can once again use Unity tech with its own SpatialOS as it is no longer in breach of the middleware's terms of service. However, they are not an official partner of the engine firm meaning that the tech integration might not be perfect.
Our sister-site PCGamesInsider.biz has the full story.