# Fucking Approachable Swift Concurrency
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A no-bullshit guide to understanding Swift concurrency. Learn async/await, actors, Sendable, and MainActor with simple mental models.
**[Visit the site](https://fuckingapproachableswiftconcurrency.com)**
## About
Swift concurrency can be confusing. This site distills the best resources into clear, approachable mental models that anyone can understand.
In the tradition of [fuckingblocksyntax.com](https://fuckingblocksyntax.com/) and [fuckingifcaseletsyntax.com](https://fuckingifcaseletsyntax.com/).
## Topics Covered
- **Async/Await** - Suspension vs blocking, and why it matters
- **Tasks** - Managing async work with Task and TaskGroup
- **Isolation** - The core mental model for Swift concurrency (MainActor, actors, nonisolated)
- **Sendable** - What can safely cross isolation boundaries
- **Isolation Inheritance** - How isolation flows through your code
- **Common Mistakes** - And how to avoid them
## Languages
Available in 14 languages: English, Spanish, Ukrainian, Portuguese (BR & PT), Arabic, Korean, Japanese, Chinese (Simplified & Traditional), Russian, Turkish, French and Polish.
## Development
This site is built with [Eleventy](https://www.11ty.dev/).
### Prerequisites
- [mise](https://mise.jdx.dev/) (for managing Node.js and pnpm)
### Setup
```bash
mise install
pnpm install
```
### Development Server
```bash
pnpm dev
```
Then open **http://localhost:8080/** in your browser.
### Build
```bash
pnpm build
```
## Credits
Much of this guide is distilled from [Matt Massicotte's](https://www.massicotte.org/) excellent work on Swift concurrency.
## License
MIT License - see [LICENSE.md](LICENSE.md)
## Contributors ✨
Thanks goes to these wonderful people ([emoji key](https://allcontributors.org/docs/en/emoji-key)):
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<td align="center" valign="top" width="14.28%"><a href="https://github.com/AkshayAShah"><img src="https://avatars.githubusercontent.com/u/148655?v=4?s=100" width="100px;" alt="Akshay"/><br /><sub><b>Akshay</b></sub></a><br /><a href="#content-AkshayAShah" title="Content">🖋</a></td>
<td align="center" valign="top" width="14.28%"><a href="https://peterspath.net"><img src="https://avatars.githubusercontent.com/u/211143281?v=4?s=100" width="100px;" alt="Peter's Path"/><br /><sub><b>Peter's Path</b></sub></a><br /><a href="#content-peterspath" title="Content">🖋</a></td>
<td align="center" valign="top" width="14.28%"><a href="http://www.stormacq.com"><img src="https://avatars.githubusercontent.com/u/401798?v=4?s=100" width="100px;" alt="Sébastien Stormacq"/><br /><sub><b>Sébastien Stormacq</b></sub></a><br /><a href="#content-sebsto" title="Content">🖋</a></td>
<td align="center" valign="top" width="14.28%"><a href="https://github.com/exproot"><img src="https://avatars.githubusercontent.com/u/72192187?v=4?s=100" width="100px;" alt="Ertan"/><br /><sub><b>Ertan</b></sub></a><br /><a href="https://github.com/tuist/fuckingapproachableswiftconcurrency/commits?author=exproot" title="Documentation">📖</a></td>
<td align="center" valign="top" width="14.28%"><a href="https://vikram.kriplaney.com"><img src="https://avatars.githubusercontent.com/u/55100?v=4?s=100" width="100px;" alt="Vikram Kriplaney"/><br /><sub><b>Vikram Kriplaney</b></sub></a><br /><a href="#content-markiv" title="Content">🖋</a></td>
<td align="center" valign="top" width="14.28%"><a href="https://github.com/krzyszt0xF"><img src="https://avatars.githubusercontent.com/u/10384246?v=4?s=100" width="100px;" alt="Krzysztof"/><br /><sub><b>Krzysztof</b></sub></a><br /><a href="https://github.com/tuist/fuckingapproachableswiftconcurrency/commits?author=krzyszt0xF" title="Code">💻</a></td>
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This project follows the [all-contributors](https://github.com/all-contributors/all-contributors) specification. Contributions of any kind welcome!