# .NET Source-Build
Please use [GitHub
discussions](https://github.com/dotnet/source-build/discussions) to see
announcements, ask questions, make suggestions, and share information with other
members of the source-build community.
This repo is the starting point for building .NET from source. It contains
documentation, tools, and is used for issue tracking.
## Prerequisites
* [Build system requirements](Documentation/system-requirements.md)
## Building .NET
Follow the instructions in [dotnet/dotnet's
README](https://github.com/dotnet/dotnet/blob/main/README.md#dev-instructions)
to build .NET from source.
## Source-build goals
There are two primary goals of the source-build effort:
1. Increase .NET adoption by focusing on making .NET available everywhere
If .NET was available everywhere - including Linux distributions and package
managers like Homebrew - as a first class citizen, it would make .NET a more
attractive option for developers who might otherwise look at other languages
or runtimes. Users would be more likely to start using and keep using .NET if
.NET is available on their development and release platforms of choice.
To achieve this, we try to make it easier for community and partner
maintainers to build and release .NET for their platforms. We need to make
sure source-build satisfies the official packaging rules of commonly used
Linux distributions, such as
[Fedora](https://fedoraproject.org/wiki/Packaging:Guidelines) and
[Debian](https://www.debian.org/doc/manuals/maint-guide/build.en.html). Many
Linux distributions have similar rules. These rules tend to have three main
principles:
* Limited or no network access
* Consistent reproducibility
* Source code for everything
2. Make maintenance of the .NET product easier
The current way of making changes to .NET during a servicing release is to
make changes to individual product repositories and then adjust the
dependency versions to flow the changes to the next set of repositories. This
is repeated until all the repositories are updated. If there's an issue
discovered late in the release cycle, the fixes and the dependency updates
need to be re-done quickly, which becomes difficult. It's also difficult to
verify that the issue is fixed in the final product. It would be much easier
to make and test product-wide changes if we could make atomic changes to one
repository and be able to build the whole product based on that source code
at once.
In addition, getting source-build fully functional would provide everyone
with a place to try changes that would otherwise require a lot of
coordination between multiple repositories - such as landing features that
require changes to both the runtime and the SDK.
For more details about this Unified Build, see [this
overview](https://github.com/dotnet/dotnet/blob/main/docs/Overview.md).
Source-build can help achieve both these goals by making it easier for everyone
to build and release the entire .NET product end-to-end.
## What does the source-build infrastructure do?
Source-build solves common challenges that most developers encounter when trying
to build the whole .NET SDK from source.
* .NET is composed of many repositories that need to be built at a specific
combination of commits.
* Each repository's build output needs to flow into the next repository's build.
* By default, most .NET repositories download prebuilt binary dependencies from
online sources. These are forbidden by typical Linux distribution rules, and
interfere with build output flow.
* Some of the binary build dependencies are under a proprietary license, making
it difficult to build everything without taking accidental dependencies on
non-Open Source code. Many of our community members and partners want to build
an Open Source .NET only.
* Flowing the build output automatically also means we can make and test changes
that require coordination across a number of repositories.
* Nearly all .NET repositories require the .NET SDK to build. This is a circular
dependency, which presents a bootstrapping problem, whether that's bringing up
new architectures (eg, riscv), or support new operating systems (eg, FreeBSD).
* Microsoft controls the SDKs used by `dotnet-install.sh` scripts and
`Microsoft.*` and `runtime.*` nuget packages at nuget.org; source-build makes
it possible for the community to bring up the platforms without Microsoft
having to accept/bless things.
## Comprehensive Guidelines
* [Bootstrapping new distro and architecture
guidelines](Documentation/bootstrapping-guidelines.md)
* [Distribution packaging
guidelines](https://learn.microsoft.com/dotnet/core/distribution-packaging)
## .NET in Linux Distributions
| Distro | Package Feed | Maintainer |
|---|---|---|
| Alpine | [Community](https://pkgs.alpinelinux.org/packages?name=dotnet*&branch=v3.16&repo=&arch=&maintainer=) | [@ayakael](https://github.com/ayakael) |
| Arch Linux | [Community](https://archlinux.org/packages/?q=dotnet)<br>[Arch User Repo](https://aur.archlinux.org/packages?K=dotnet) | [@alucryd](https://github.com/alucryd) |
| CentOS Stream | [CentOS Stream Mirror](http://mirror.stream.centos.org/9-stream/AppStream/x86_64/os/Packages/) | [@omajid](https://github.com/omajid) |
| [Fedora](https://fedoraproject.org/wiki/DotNet) | [Default](https://packages.fedoraproject.org/search?query=dotnet) | [@omajid](https://github.com/omajid) |
| Homebrew | [Formula](https://formulae.brew.sh/formula/dotnet) | [@asbjornu](https://github.com/asbjornu) |
| [Red Hat Enterprise Linux](https://developers.redhat.com/products/dotnet/overview) | [Default](https://access.redhat.com/documentation/en-us/net/8.0) | [@omajid](https://github.com/omajid) |
| [Ubuntu](https://canonical.com/blog/install-dotnet-on-ubuntu) | [Default](https://packages.ubuntu.com/search?suite=default§ion=all&arch=any&keywords=dotnet&searchon=names)<br>[Personal Package Archives](https://launchpad.net/ubuntu/+ppas?name_filter=dotnet) | [@mirespace](https://github.com/mirespace) |
## Support
.NET source build supports the following:
1. Linux only, Windows and MacOS is not supported
1. 1xx SDK feature band only (e.g. 8.0.1xx)
For the latest information about Source-Build support for new .NET versions,
please check our [GitHub Discussions
page](https://github.com/dotnet/source-build/discussions) for announcements.
* [More information about .NET
Versioning](https://docs.microsoft.com/en-us/dotnet/core/versions/)
* [More information about .NET Support
Policies](https://dotnet.microsoft.com/en-us/platform/support/policy/dotnet-core)
## License
This repo is licensed under the [MIT](LICENSE.txt) license.