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README.md

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+# eventbus
+Straightforward EventBus for Go 1.18+
+
+[![Documentation](https://pkg.go.dev/badge/github.com/JosiahWitt/eventbus)](https://pkg.go.dev/github.com/JosiahWitt/eventbus)
+[![CI](https://github.com/JosiahWitt/eventbus/workflows/CI/badge.svg)](https://github.com/JosiahWitt/eventbus/actions?query=branch%3Amain+workflow%3ACI)
+[![codecov](https://codecov.io/gh/JosiahWitt/eventbus/branch/main/graph/badge.svg)](https://codecov.io/gh/JosiahWitt/eventbus)
+<!-- Hiding the Go Report Card until they support generics -->
+<!-- [![Go Report Card](https://goreportcard.com/badge/github.com/JosiahWitt/eventbus)](https://goreportcard.com/report/github.com/JosiahWitt/eventbus) -->
+
+## Go Version Support
+Go 1.18+ is required, due to the use of generics
+
+
+## Project Status
+Unlike some of my other projects that are used in production (eg. [ensure](https://github.com/JosiahWitt/ensure) for testing and [erk](https://github.com/JosiahWitt/erk) for errors), this project is _currently more on the experimental side_. It has good test coverage, but I haven't actually built anything serious with it (yet!). So, please **use at your own risk**! Oh, and if you do use it for something serious, let me know how it works out!
+
+
+## Install
+### Library
+```bash
+$ go get github.com/JosiahWitt/eventbus
+```
+
+
+## About
+This package provides a straightforward concurrent, typed EventBus for Go 1.18+, supporting fanout, and in order, only once delivery.
+
+
+## Examples
+
+Please see the [`examples`](./examples/) directory for complete examples, such as the [Simple Chat App](./examples/simplechatapp/).
+
+### Basic Usage
+```go
+type Message struct { Body string }
+
+bus := eventbus.New[*Message]()
+
+// In one goroutine:
+sub := bus.Subscribe("chatroom:123", "user:456")
+for msg := range sub.Channel() {
+  // Do something with msg
+}
+// Eventually...
+sub.Unsubscribe()
+
+// In another goroutine:
+bus.Publish(&Message{Body: "Hello, World!"}, "chatroom:123", "user:789")
+bus.Publish(&Message{Body: "Go is fun!"}, "chatroom:456", "user:456")
+bus.Publish(&Message{Body: "Wordle 1/6"}, "chatroom:456", "user:789")
+bus.Publish(&Message{Body: "Bonjour!"}, "chatroom:123", "user:456")
+
+// sub will receive:
+//  1. Hello, World!
+//  2. Go is fun!
+//  3. Bonjour!
+// Each of those messages is published to one or both of `chatroom:123` and `user:456`.
+//
+// sub will not receive "Wordle 1/6", because that was published to neither `chatroom:123` nor `user:456`.
+```