.Net IOC container built from the ground up to support the .Net Standard 1.1 profile (and therefore supporting Asp.Net Core and Xamarin environments). It's fast, very extensible, and has a lot of cool features. Try it now!
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Rezolver is a high performance, portable (.NetStandard 1.1 & 2.0), open-source IOC container.

You can get the Rezolver Package from Nuget, and for more packages, head over to the packages documentation.

For more information, including API reference and developer how-tos, head on over to the Rezolver website.

Follow us on twitter for code or documentation updates/release notifications etc.

Work in Progress Items ready to go

Version Highlights


Primary purpose of this release was to have a build that's been built and tested explicitly against the .Net Core 2.1 runtime and Asp.Net Core 2.1.

  • Added SourceLink Support
  • Core library now targets .NetStandard1.1, .NetStandard2.0 and net45 (Removed net461 as it was pointless)

Asp.Net Core 2.1 Integration

  • Rezolver.Microsoft.AspNetCore.Hosting updated dependency to Asp.Net Core 2.1
  • Rezolver.Microsoft.Extensions.DependencyInjection updated dependency to Asp.Net Core 2.1


As always, for the full list of changes, check out the version history.

Bugfixes for generics handling, specifically:

  • Singletons matched contravariantly or covariantly did not honour the pattern
  • Registering Foo<T, U> : IFoo<IBar<T, U>> against <IFoo<IBar<,>> caused an IndexOutOfRangeException


  • Generic covariance
  • Mixed variance
  • Enumerable Projections
  • List member bindings (collection initialisation)
  • Selection of constructors on open generics
  • Fluent API to build per-member bindings

1.3 & 1.3.1

  • Support for Asp.Net Core 2.0
  • Contravariance
  • Decorator Delegates
  • List, Collection and Array injection
  • ... Plus loads of bug fixes and other enhancements :)

All these features are documented on our website.


Rezolver has now been incorporated into @DanielPalme's excellent IOCPerformance benchmark.

Read our own notes on Rezolver's performance in this benchmark, which provide some context on the areas where it can be improved.

Hint: Unless you're creating child containers with additional registrations, Rezolver's performance is right up there with the fastest.


Feel free to fork this repo, build from the source, and submit pull requests for new functionality or bugfixes!