Xcode 10.2 Beta 1 was released on 24 Jan 2019 and requires macOS 10.14+.
It can be downloaded from https://download.developer.apple.com/Developer_Tools/Xcode_10.2_beta/Xcode_10.2_beta.xip.
Release notes are located at https://developer.apple.com/documentation/xcode_release_notes/xcode_10_2_beta_release_notes.
The SDKs it contains are:
- iOS 12.2 (Build 16E5181e)
- macOS 10.14.4 (Build 18E174e)
- tvOS 12.2 (Build 16L5181e)
- watchOS 5.2 (Build 16T5181e)
The compilers it contains are:
- clang 10.0.1 (Build 1001.0.37.7)
- swift 5.0 (Build 1001.0.45.7)