DeepSeek

DeepSeek is a Chinese AI assistant built on the company's own models, several of which have been released with open weights and are widely run by developers outside the company.

It is strong at reasoning tasks and code, and the open releases in particular changed expectations about what capability is achievable at a given training cost.

The hosted assistant is free to use for most purposes, and the open models can be run locally or self-hosted, which matters for anyone who cannot send data to a third-party service.