Watermill

Quick takeaways Solve real problems first - successful open source projects start by addressing actual needs, not by looking for problems to fit a solution Keep breaking changes minimal - Watermill stayed on v1 for 6 years with no breaking changes in the core library, building trust with users Examples and documentation are crucial - provide real-world examples with automated tests, not just simple “hello world” demos Promotion matters - creating a great library isn’t enough; you need to actively share it through conferences, blog posts, and communities Be patient with growth - Watermill took 7 years to reach 8,000 stars; overnight success in open source is rare Introduction In this episode, we share the story of how Watermill, our event-driven library for Go, grew from a side project to a popular open source library with over 8,000 GitHub stars and 100+ contributors.

It’s Autumn over here, and it usually means another release of Watermill! 🍂 It’s hard to believe it’s already been five years since the v1.0 release. In case you’re new to Watermill, here’s TL;DR. Watermill is a Go library for building message-driven or event-driven applications the easy way. Think of it like an HTTP router but for messages. It’s a library, not a framework, so you don’t need to change your architecture to use it.

In the previous post, I looked into running transactions in a layered architecture. Now, let’s consider transactions that need to span more than one service. If you work with microservices, a time may come when you need a transaction running across them. Especially if the way they are split was an afterthought (the unfortunate but likely scenario). Service A calls service B, which calls service C, and if something goes wrong at the end, the system becomes inconsistent.

In case you missed the memo, the Single Page Application hype period is over, and we’re now back to PHP and jQuery, I mean rendering HTML on the server. I’m excited! It brings me back to the early 2000s when we were all web developers, not frontend or backend engineers. But there’s one thing I would miss from the SPA era: live updates.

Hey, it’s been a long time! We’re happy to share that Watermill v1.3 is now out! What is Watermill Watermill is an open-source library for building message-driven or event-driven applications the easy way in Go. Our definition of “easy” is as easy as building an HTTP server in Go. With all that, it’s a library, not a framework. So your application is not tied to Watermill forever.

After almost three years since the last stable release, Watermill v1.2 is finally out! If you’re new here, Watermill is our open-source library for building event-driven applications in Go, the easy way. A lot has happened since v1.1. We’ve been running Watermill on production in many projects, using it in new ways and adding features to support new use cases. We also received a lot of feedback and contributions from the community.

If you compare MySQL or PostgreSQL with Kafka or RabbitMQ, at first, it seems they are entirely different software. And usually, that’s true, as you would use them for quite different tasks. What they have in common is processing streams of data, and they specialize in specific ways of doing it. While Kafka and RabbitMQ are popular examples of Pub/Subs (also known as message queues or stream processing platforms), I’d like to share some patterns for using SQL databases as Pub/Subs as well.

54 days of work, 12,909 lines of code, 47 Monsters and 42 KFC Twisters later finally it is Watermill v0.3.0! To keep it short, let’s go through the changes. One important thing: at the end of this post there is a 3 question survey. Please take a moment to fill it out, it will help us make Watermill even better.

This post is a quick how-to for starting a new project in Go. It features: Hot code reloading Running multiple Docker containers with Docker Compose Using Go Modules for managing dependencies It’s best to show the above working together with an example project. We’re going to set up two separate services communicating with messages over NATS. The first one will receive messages on an HTTP endpoint and then publish them to a NATS topic.

Let me start by thanking all contributors for feedback on Watermill - it drives us to add new features. Thanks! It’s been almost a month since the initial release of Watermill. However, it’s just the beginning and we are still working hard to ship new features. What is new in Watermill 0.2? Documentation - watermill.io Godoc is great. However, it’s functionality is sometimes too limited to express more complicated documentation.

Watermill is a Go library for working efficiently with message streams. It is intended as a library for building event-driven applications, enabling event sourcing, CQRS, RPC over messages, sagas. Why? Lack of standard messaging library There are many third party and standard library tools which help to implement standardized RPC or HTTP communication in Golang. There are also multiple third party HTTP routers and frameworks.