You might have heard of “state machine” or “finite-state machine” before. If you look up state machine on Wikipedia, you’ll read that a state machine is described as a “mathematical model of computation,” followed by a bunch of symbols and computer science jargon that doesn’t immediately seem to apply to your team’s work.
However, state machines are really useful for describing almost any kind of logic, feature, user story, sequence, process, workflow, specification, and more.
State machines are great for modeling state in applications. However, we often need to persist and restore state across sessions - for example, when a user closes and reopens their browser. In this article, we’ll explore how to persist and restore state in XState so your frontend applications or backend workflows can pick up where it left off.
At Stately, the Actor Model is one of our favorite programming paradigms, and we think it’s for good reason! The actor model allows developers to build reliable message-based systems by using actors to communicate. This works extremely well with state machines and statecharts, which can also be modeled as actors and can communicate much in the same ways. Read on to learn what the actor model is, the problems it seeks to solve, and how you can use it in your projects to communicate reliably across different entities.
Today we’re happy to introduce another pro feature for our Stately Studio subscribers; Version History. With this feature, you can save versions of your work as you go and refer back to them in the future.
Modelling using statecharts changed my career as a dev. Of all the state management solutions I’ve tried, it feels the most complete, logical and robust. Even if you don’t use them in your app’s code, statecharts let you break down complex features into states, events, services, actions and guards.
Statecharts are a visual language used to describe the states in a process.
You may have used similar diagrams in the past to design user flows, plan databases or map app architecture. Statecharts are another way of using boxes and arrows to represent flows, but with XState these flows are also executable code that can be used to control the logic in your applications.
The finite state machine is one of the oldest models of computation in computer science. It’s older than the web, older than any programming language you can think of, and probably older than you. Just ask Mealy (1955) or Moore (1956). Finite state machines (FSMs) can be implemented in any modern language using control-flow statements, yet there’s most likely a state machine library (if not many) in all of those languages.
My code contains Horcruxes. I’m not proud to admit it, since to make a Horcrux you need to commit a murder. The murders seemed intuitive at the time, and were usually for expedience. But nonetheless, I am a murderer.
Let’s talk about how I got here.
Redux is fantastic.
Some of you might disagree, so let me tell you why.
Over the last few years, Redux has popularized the idea of using message-passing (also known as event-driven programming) to manage application state. Instead of making arbitrary method calls to various class instances or mutating data structures, we now can think of state as being in a "predictable container" that only changes as a reaction to these "events".
XState version 4.7 has just been released. This is a minor version bump, but a major reworking of the internal algorithms, a lot of new capabilities, bug fixes, and a better TypeScript experience. It also paves the road for even more utilities, like @xstate/test and @xstate/react, as well as compatibility with other 3rd-party tools across the ecosystem, and even across languages.
