The State of Reactive Extensions for .NET in 2025

2nd June 2025 · 56 min watch

By Ian Griffiths Technical Fellow I

Ian Griffiths discusses the current state of Rx.NET, its challenges, and plans for v7.0 in this hour-long talk.

About this talk

Rx.NET

Rx.NET v6.0 was released in 2023. The free Introduction to Rx.NET book was released in 2024, but progress has stalled since then. In this hour long "state of the nation" talk, lead maintainer, Ian Griffiths, delves into the details, hidden complexities and the various options on the table, current progress and plans for Rx.NET v7.0.

Contents:

00:06 - We've stalled
01:38 - The big issues
02:58 - Packaging
03:03 - Packaging problems
05:31 - Deep dive into packaging
08:48 - Packaging problems continued
09:16 - Deep dive into packaging continued
10:17 - Packaging problems continued
18:17 - Self-contained bloat on Windows
18:49 - Nuget.org example
21:36 - Self-contained bloat on Windows continued
24:12 - Difficulties fixing packaging problems
25:18 - Why a "clean break" doesn't work
27:04 - Rx packaging "gauntlet"
31:20 - I wouldn't be starting from here
33:35 - What are we doing about packaging?
35:08 - Option 1: workaround
36:39 - Option 2: split packages
38:13 - UWP
38:27 - UWP (aka uap10.0)
42:59 - What I'd like to do with UWP
43:54 - WASM
44:01 - WASM problems
46:37 - AsyncRx.NET
46:58 - AsyncRx.NET status
48:13 - System.Linq.Async
48:19 - Separation of System.Linq.Async
51:26 - TFM misperceptions
51:35 - Perception of non-support for .NET 8.0
51:57 - nuget.org example
52:54 - Perception of non-support for .NET 8.0 continued
54:04 - Why we will update the TFM anyway
54:07 - Backlog
54:19 - What about actual meaningful progress?
55:19 - Conclusion

This talk was given during endjin's internal weekly "show & tell" meeting, but has been edited for public consumption.

About the presenter

Ian Griffiths

Ian has worked across an extraordinary breadth of computing - from embedded real-time systems and broadcast television to medical imaging and cloud-scale architectures. As Technical Fellow at endjin, he brings this deep cross-domain experience to bear on the hardest technical problems.

A 17-time Microsoft MVP in Developer Technologies, Ian is the author of O'Reilly's Programming C# 12.0 and one of the foremost authorities on the C# language and high-performance .NET development. He's a maintainer of Reactive Extensions for .NET, Reaqtor, and endjin's 50+ open source projects.

Ian has created Pluralsight courses on WPF fundamentals, WPF advanced topics, WPF v4, and the TPL, and has given over 20 talks at conferences worldwide. Technology brings him joy.