Versioning and package naming

Arc4u follows semantic versioning since version 8.0.0, and every package of a release has the same version number. With Arc4u 9, the packages were also renamed from Arc4u.Standard.* to Arc4u.*. This page explains both, so that you can tell which packages and versions belong together.

How it works

Version numbers

Since 8.0.0, a version is MAJOR.MINOR.PATCH:

Part	Changes when
`MAJOR`	A release contains breaking changes.
`MINOR`	A release adds features, with bug fixes.
`PATCH`	A release contains bug fixes only.

Previews carry a -previewNN suffix, for example 9.0.0-preview37. Arc4u 9 is available only as previews so far, which is why the install commands in this documentation use --prerelease:

dotnet add package Arc4u.Caching --prerelease

All the packages are built and published together, with one version number passed to the whole build. A package therefore gets a new version even when its own code did not change, and the packages of one application should all use the same version.

The versions published on NuGet.org so far fall into these lines:

Versions	Package names	Format	Target frameworks of the last release
5.0.x.y (2021 to 2022)	`Arc4u.Standard.*`	Four parts, tied to .NET	`netstandard2.0`, `netstandard2.1`
6.0.x.y and 6.1.x.y (2022 to 2023)	`Arc4u.Standard.*`	Four parts, tied to .NET	`netstandard2.0`, `net6.0`, `net7.0`
8.0.0 to 8.3.2 (2023 to 2025)	`Arc4u.Standard.*`	Semantic versioning	`netstandard2.0`, `net8.0`, `net9.0`
9.0.0 previews (since 2025)	`Arc4u.*`	Semantic versioning	`9.0.0-preview02` to `9.0.0-preview37`: `net8.0`, `net9.0`, `net10.0` (`9.0.0-preview01`: `net8.0`, `net9.0`)

The code on the develop/9.0.0 branch, which this site documents, targets net10.0 and net11.0 (see Target frameworks).

Note

A few packages also have a stable 1.0.0 version outside these lines, for example Arc4u.Standard.Core, Arc4u.AspNetCore.Results and Arc4u.Dependency.Tool. Ignore it: dotnet add package Arc4u.Dependency.Tool without --prerelease installs 1.0.0, not a 9.0.0 preview.

Before 8.0.0, a version followed the .NET version it was built with. For example, 6.0.9.1 was built with .NET 6.0.9:

the first part was the .NET version supported,
the second part changed for a breaking change in Arc4u,
the third part was the minimum .NET patch version,
the fourth part was the Arc4u change.

There is no Arc4u 7: the Arc4u.Prism.DI.Wpf package already had 7.2.x versions, so semantic versioning started at 8.

Package names

Arc4u 9 renamed the packages by removing Standard from their IDs:

Arc4u 8.x	Arc4u 9
`Arc4u.Standard`	`Arc4u`
`Arc4u.Standard.Core`	`Arc4u.Core`
`Arc4u.Standard.<Area>`	`Arc4u.<Area>`, for example `Arc4u.Standard.Caching.Redis` becomes `Arc4u.Caching.Redis`

What the rename does and does not change:

The rename does not change namespaces. The 8.x packages already used Arc4u.* namespaces. Other changes in Arc4u 9 moved or removed some types; the migration guide lists them.
Some packages already had the new name before 9: Arc4u.AspNetCore.Results, Arc4u.Configuration.Store.EfCore and Arc4u.Prism.DI.Wpf (deprecated, not shipped in 9). Arc4u.Configuration.Store was published under its new name for 8.2.0-preview01 to 8.2.0-preview20, then as Arc4u.Standard.Configuration.Store until 8.3.2.
A package ID can differ from its folder name in the repository: Arc4u.Caching.SqlServer is built from src/Arc4u.Caching.Sql.
Paths of static web assets change. ASP.NET Core serves the files of a Razor class library under _content/<package ID>/, so the Blazor files of Arc4u.OAuth2.Blazor are now under _content/Arc4u.OAuth2.Blazor/.
Some packages were not carried over to Arc4u 9, and some are new. The package support page lists the status of each one.

The complete list of renamed packages is in Package renames in the migration guide.

Why Arc4u works this way

A version number should say what changed. In the four-part scheme, the first and third parts described .NET rather than Arc4u, and because Arc4u supports several .NET versions at once they no longer said much. It was not possible to tell from a version whether it brought new features or only followed a .NET update. Semantic versioning answers that question.
One version for all packages removes the need for a compatibility table: packages with the same version were built and tested together.
The Standard suffix no longer meant anything. It dates from the packages that targeted .NET Standard only (the 5.x packages target only netstandard2.0 and netstandard2.1). Arc4u 9 targets current .NET versions only, except Arc4u.Dependency, which also targets netstandard2.0, and the Arc4u.Dependency.Tool source generators, which target netstandard2.0 as source generators must.

Trade-offs

Previews are not stable. An API can change between two 9.0.0-previewNN versions. Read the changelog before you move to a newer preview.
New versions without changes. Because all packages share a version, upgrading one means upgrading all, even those whose code is identical.
Two package families. The Arc4u.Standard.* 8.x packages are still on NuGet.org next to the Arc4u.* 9 packages. They contain the same namespaces and type names, so do not reference both families in one application.

In Arc4u

To keep every Arc4u package on the same version, use central package management and define the version once:

<!-- Directory.Packages.props -->
<Project>
  <PropertyGroup>
    <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
    <Arc4uVersion>9.0.0-preview37</Arc4uVersion>
  </PropertyGroup>
  <ItemGroup>
    <PackageVersion Include="Arc4u.Caching" Version="$(Arc4uVersion)" />
    <PackageVersion Include="Arc4u.Diagnostics" Version="$(Arc4uVersion)" />
  </ItemGroup>
</Project>

To upgrade an application from the Arc4u.Standard.* 8.x packages, follow the migration guide.

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