[Home](../) › [Blog](../blog) › Metalama 2026.1 Generally Available: First LTS Release, Complete C# 14 Support, and a Redesigned Redis Backend # Metalama 2026.1 Generally Available: First LTS Release, Complete C# 14 Support, and a Redesigned Redis Backend > Announcing the general availability of Metalama 2026.1, our first long-term support release: complete C# 14 support in aspects, new initialization and parameter-introduction advice, a redesigned Redis caching backend, fewer third-party dependencies, and over 100 bug fixes. Published: 2026-06-03 · Author: Gaël Fraiteur · Canonical: https://postsharp.net/blog/metalama-2026-1-ga Metalama 2026.1 is now generally available, and it's our first **long-term support (LTS)** release. This is a consolidation release: we finished the C# 14 work we started in 2026.0, extended the advising API, redesigned the Redis caching backend, cut several third-party dependencies, and closed most of the bug backlog. The packages are on [NuGet.org](https://www.nuget.org/packages/Metalama.Framework), and the Visual Studio extension is on the [Visual Studio Marketplace](https://marketplace.visualstudio.com/items?itemName=PostSharpTechnologies.PostSharp). For the complete list of changes, see the [release notes](https://doc.metalama.net/conceptual/release-notes/release-notes-2026-1). ## Complete C# 14 support in aspects In 2026.0 we supported all C# 14 features in your own code but left a few gaps in aspects. Those gaps are now closed: - **Introducing extension blocks.** The new [IntroduceExtensionBlock](https://doc.metalama.net/api/metalama-framework-aspects-adviserextensions-introduceextensionblock) advice lets aspects add extension blocks to static classes. See [Introducing types](https://doc.metalama.net/conceptual/aspects/advising/introducing-types). - **Contracts on extension-block receiver parameters.** You can now add a contract to the receiver parameter of an extension block, and it propagates across the extension members. - **Introducing user-defined compound assignment operators.** Operators such as `+=`, `-=`, and `*=` can now be introduced through [IntroduceMethod](https://doc.metalama.net/conceptual/aspects/advising/introducing-members). - **Run-time invoker interfaces for extension members.** - **Introducing parameters into partial constructors.** Two C# 14 constructs remain unsupported *inside templates*: null-conditional assignments (`x?.P = v`) and the `field` keyword. Rather than fail confusingly, Metalama now detects them and reports a clear diagnostic (`LAMA0101`). ## Initialization advice We've extended the [initialization advice](https://doc.metalama.net/conceptual/aspects/advising/initializers) with two new initializer kinds and better support for records: - **`AfterLastInstanceConstructor`** injects code into a `protected virtual OnConstructed` method, so it runs once after the most-derived constructor completes. - **`AfterObjectInitializer`** runs after the constructor and any object initializer or `with` expression have completed. Metalama makes the target implement `IInitializable` and rewrites the call sites accordingly, so you can validate or compute derived state once every property has been set. - **`BeforeInstanceConstructor`** now works on positional records with primary constructors. - **[Constructor parameter introduction](https://doc.metalama.net/conceptual/aspects/advising/introducing-constructor-parameters)** can now generate forwarding overloads, so you can add a parameter without breaking binary compatibility. ## Dependency injection [IntroduceParameterAndPull](https://doc.metalama.net/api/metalama-framework-advising-pullstrategy-introduceparameterandpull) now accepts a `reuseExistingParameterOfCompatibleType` argument. When a chained constructor already accepts a parameter of the same or a more specific type, the existing parameter is forwarded instead of duplicated. The default .NET DI adapter relies on this: an aspect that pulls an `ILogger` no longer adds a second `ILogger` parameter when the target constructor already has one. See [Injecting dependencies into aspects](https://doc.metalama.net/conceptual/aspects/dependency-injection). ## Redesigned Redis caching backend [Metalama.Patterns.Caching.Backends.Redis](https://doc.metalama.net/patterns/caching/redis) received a major overhaul, porting the work we did for PostSharp 2025.1 (see [Breaking Update of PostSharp Caching adapter for Redis in 2025.1](https://postsharp.net/blog/redis-caching-update)): - **New data schema.** Reading a cache item is now a single, observationally-consistent operation, and cache keys are versioned. - **Cluster support.** Hash tags keep related keys on the same shard, and you can configure `ReadCommandFlags` and `WriteCommandFlags` for multi-node setups. - **Retry and exception-handling policies.** The new `IRetryPolicy` and `IExceptionHandlingPolicy` interfaces give you exponential backoff and centralized error handling. - **Key compression.** Keys longer than a configurable threshold (128 characters by default) are hashed automatically with `XxHash64` or `XxHash128`. - **Overload detection.** The `IsBackgroundTaskQueueOverloaded` property lets you back off under pressure, and the dependency garbage collector pauses itself when the queue is saturated. If you use the Redis backend, note that the schema change requires purging the cache (`FLUSHDB`) on upgrade. See the breaking changes below. ## Fewer third-party dependencies We reduced our dependency surface to improve supply-chain safety: - `System.Text.Json` replaces `Newtonsoft.Json`. - `System.IO.Hashing` replaces `K4os.Hash` (the xxHash implementation now comes from the .NET runtime). - Diff-tool integration moved to the optional `Metalama.Extensions.DiffEngine` package, and HTML test output moved to `Metalama.Extensions.HtmlWriter` (both used in [aspect snapshot testing](https://doc.metalama.net/conceptual/aspects/testing/snapshot-testing)). - We no longer use MD5 for non-cryptographic hashing. ## Performance improvements This release improves both build-time and design-time performance. At build time, configuration files now use `System.Text.Json` source generators, polymorphic pattern matching in the code model was restructured to match on `DeclarationKind` or `TypeKind`, and the WPF temporary compilation phase (`MarkupCompilePass1`) runs a reduced pipeline that emits member signatures only and skips the linker step. At design time, the protocol between the analyzer and the design-time services moved from JSON to MessagePack. ## Bug fixes We fixed over 100 bugs in this release, spanning the template engine, linker, code model, design-time services, dependency injection, and diagnostics. Metalama 2026.1 is the first release ever to ship with (almost) zero known bugs. ## Breaking changes A few changes may affect existing code: - `AddInitializer` ordering now respects `AspectOrderDirection.RunTime`. - `IntroduceParameter` on a record primary constructor no longer materializes the parameter by default; opt in with `materializeOnRecord`. - `IConstructor.InitializerKind` returns `Base` (instead of `None`) for an implicit `base()` call. - `IEvent.RaiseMethod` returns `null` for non-raisable events. Use `IEventInvoker.CanRaise`. - The test base classes `AspectTestClass`, `DefaultAspectTestClass`, `CurrentDirectoryAttribute`, and `CurrentProjectAttribute` were removed. - For the Redis backend: the schema redesign requires a cache purge, `ExceptionHandlingCachingBackendEnhancer` was removed in favor of the `ExceptionHandlingPolicy` property, and `TransactionMaxRetries` and `CacheCleanupOptions.Sequential` are obsolete. See the [release notes](https://doc.metalama.net/conceptual/release-notes/release-notes-2026-1#breaking-changes) for the full list. ## What's next As our first LTS release, 2026.1 is the version to standardize on if you want stability. The next feature release is expected to be 2027.0, with support for .NET 11. Work will start in late August, and we don't expect any larger work on Metalama in the meantime. Found an issue or have a feature request? Let us know on [GitHub](https://github.com/metalama/Metalama/issues). Happy meta-programming! -gael --- ## Site navigation - Index of the whole site: [llms.txt](../llms.txt)