If you want to stay on top of the proposed changes to the Swift programming language then this repository is worth a browse https://github.com/apple/swift-evolution

This repository tracks the ongoing evolution of Swift. It contains:

Goals for upcoming Swift releases (this document). The Swift evolution review schedule tracking proposals to change Swift. The Swift evolution process that governs the evolution of Swift. Commonly Rejected Changes, proposals which have been denied in the past. This document describes goals for the Swift language on a per-release basis, usually listing minor releases adding to the currently shipping version and one major release out. Each release will have many smaller features or changes independent of these larger goals, and not all goals are reached for each release.