Mark Erikson
Mark Erikson
Mark Erikson is a Senior Front-End Engineer at Replay, and lives in southwest Ohio, USA. Mark is a Redux maintainer, creator of Redux Toolkit, and general keeper of the Redux docs. He tweets at @acemarke, and blogs at https://blog.isquaredsoftware.com. He spends much of his time answering questions about React and Redux anywhere there's a comment box on the internet, and usually hangs out in the Reactiflux chat channels.
React Summit 2024React Summit 2024
Upcoming
Why You Should Use Redux in 2024
I've always avoided trying to do sales pitches for Redux, and tbh most of my time has been spent telling people when they _shouldn't_ use Redux :) But I still see lots of folks asking "_when_ should I use Redux?", and "how does Redux compare to $OTHER_TOOL?". So, I figure it's worth actually doing a talk where I cover the actual benefits and reasons to consider using Redux today.
React Day Berlin 2023React Day Berlin 2023
8 min
What's New in Redux Toolkit 2.0
Redux Toolkit 2.0 is here! Find out what's changedand why, the work that's gone into repackaging the Redux libraries, an overview of new features and breaking changes, and a look at future plans.
React Summit US 2023React Summit US 2023
7 min
Modern Redux With Redux Toolkit
Redux Toolkit 2.0 is coming Soon (TM)! Find out what's changing and why, the work that's gone into repackaging the Redux libraries, an overview of new features and breaking changes, and the latest status on the release plans.
React Advanced Conference 2023React Advanced Conference 2023
31 min
Building Better React Debugging with Replay Analysis
React's component model and one-way data flow give us a great mental model for building our apps, but debugging React apps can still be confusing. React's internals are a black box, and it's often hard to understand why components rendered or what caused errors.
The Replay time-travel debugger makes it easier to debug React apps by letting you inspect what's happening at any point in time. But what if we could go beyond the usual debugger features, and build new debugging features that tell us more about what React is doing? Let's see how Replay's API makes that possible.
TypeScript Congress 2023TypeScript Congress 2023
31 min
Publishing TS Libraries for Fun and Profit
Publishing libraries to NPM is easy - just `tsc && npm publish` and you're done, right?

Whoops, you forgot proper ESM compat. And a user is asking for a UMD build. And it doesn't work in Webpack 4. And `moduleResolution: "node16"` can't find the types.

Publishing libraries today is _complicated_. We'll take a look at the many problems and questions you should consider when publishing a package, and some hard-earned possible answers to those questions.type
React Summit 2023React Summit 2023
24 min
Debugging JS
As developers, we spend much of our time debugging apps - often code we didn't even write. Sadly, few developers have ever been taught how to approach debugging - it's something most of us learn through painful experience.  The good news is you _can_ learn how to debug effectively, and there's several key techniques and tools you can use for debugging JS and React apps.
React Advanced Conference 2022React Advanced Conference 2022
25 min
A Guide to React Rendering Behavior
Top Content
React is a library for "rendering" UI from components, but many users find themselves confused about how React rendering actually works. What do terms like "rendering", "reconciliation", "Fibers", and "committing" actually mean? When do renders happen? How does Context affect rendering, and how do libraries like Redux cause updates? In this talk, we'll clear up the confusion and provide a solid foundation for understanding when, why, and how React renders. We'll look at: - What "rendering" actually is - How React queues renders and the standard rendering behavior - How keys and component types are used in rendering - Techniques for optimizing render performance - How context usage affects rendering behavior| - How external libraries tie into React rendering
TypeScript Congress 2022TypeScript Congress 2022
30 min
Lessons from Maintaining TypeScript Libraries
Maintaining widely-used JS libraries is already complicated, and TypeScript adds an additional set of challenges.

Join Redux maintainer Mark Erikson for a look at some of the unique problems TS library maintainers face, and how the Redux team has handled those problems. We'll cover:

- Tradeoffs of different ways to define TS types for a library
- How to target different versions of TS, and considerations for determining the supported version range
- Migrating existing JS libraries to TS
- Differences between writing "app" types and "library" types
- Managing and versioning public types APIs
- Tips and tricks used by types from the Redux libraries
- TS limitations and possible language-level improvements