[It's out](https://github.com/status-im/nim-chronos/pull/494)!
v4 is the async/await framework release where we circle back experience from building libraries for [p2p networking](https://github.com/status-im/nim-libp2p), [standards-compliant websockets](https://github.com/status-im/nim-websock), [REST](https://github.com/status-im/nim-presto/) and [JSON-RPC](https://github.com/status-im/nim-json-rpc/) and of course a bunch of applications using these libraries into the core infrastructure layer, providing a stable base to continue building on. Features: * Exception effects / raises for async procedures helping you write more efficient leak-free code * Cross-thread notification mechanism for suitable building channels, queues and other multithreaded primitives * Async process I/O * IPv6 dual stack support * HTTP middleware support allowing multiple services to share a single http server * A new [documentation web site](https://status-im.github.io/nim-chronos/) covering the basics, with several simple examples for getting started * Implicit returns, support for `results.?` and other conveniences * Rate limiter * Revamped cancellation support with more control over the cancellation process * Efficiency improvements with `lent` and `sink` See the [porting](https://status-im.github.io/nim-chronos/porting.html) guides for porting code from earlier `chronos` releases (as well as asyncdispatch) See also the [release candidate](https://forum.nim-lang.org/t/10666) post for more background.
