After creating MolSeeker and iBabel4 I've been investigating the use of Swift and in particular the open-source use.

Swift.org provides a nice introduction and overview, it also highlights the Google Summer of Code Swift projects which are a fabulous way for students to get involved.

The Google Swift for TensorFlow group have been very active, and Tyrolabs have recently posted a detailed summary, including a comparison with other languages.

Two years ago, a small team at Google started working on making Swift the first mainstream language with first-class language-integrated differentiable programming capabilities. The scope and initial results of the project have been remarkable, and general public usability is not very far off.

They have now provided support for Jupyter notebooks https://github.com/google/swift-jupyter

There is also an interesting blog post here fast.ai.

IBM also seem to be using swift https://developer.ibm.com/technologies/swift/ and are highlighting leveraging Watson.

Developers can take advantage of the Watson Developer Cloud’s Swift SDK to easily build Watson-powered applications for iOS or Linux platforms. Leverage the power of Watson’s advanced artificial intelligence, machine learning, and deep learning techniques to understand unstructured data and engage with users in new ways.

Since Swift is a relatively new language it is worth looking at the ongoing evolution.