# When to use Lambda's OS-only runtimes
<a name="runtimes-provided"></a>

Lambda provides [managed runtimes](lambda-runtimes.md) for Java, Python, Node.js, .NET, and Ruby. To create Lambda functions in a programming language that is not available as a managed runtime, use an OS-only runtime (the `provided` runtime family). There are three primary use cases for OS-only runtimes:
+ **Native ahead-of-time (AOT) compilation**: Languages such as Go, Rust, Swift, and C\$1\$1 compile natively to an executable binary, which doesn't require a dedicated language runtime. These languages only need an OS environment in which the compiled binary can run. You can also use Lambda OS-only runtimes to deploy binaries compiled with .NET Native AOT and Java GraalVM Native Image.

  You must include a runtime interface client in your binary. The runtime interface client calls the [Using the Lambda runtime API for custom runtimes](runtimes-api.md) to retrieve function invocations and then calls your function handler. Lambda provides runtime interface clients for [Rust](lambda-rust.md), [Go](golang-package.md#golang-package-mac-linux), [.NET Native AOT](dotnet-native-aot.md), [Swift](https://github.com/awslabs/swift-aws-lambda-runtime) (experimental), and [C\$1\$1](https://github.com/awslabs/aws-lambda-cpp) (experimental).

  You must compile your binary for a Linux environment and for the same instruction set architecture that you plan to use for the function (x86\$164 or arm64).
+ **Third-party runtimes**: You can run Lambda functions using off-the-shelf runtimes such as [Bref](https://bref.sh/docs/news/01-bref-1.0.html#amazon-linux-2) for PHP.
+ **Custom runtimes**: You can build your own runtime for a language or language version that Lambda doesn't provide a managed runtime for, such as Node.js 19. For more information, see [Building a custom runtime for Amazon Lambda](runtimes-custom.md). This is the least common use case for OS-only runtimes.

Lambda supports the following OS-only runtimes:


| Name | Identifier | Operating system | Deprecation date | Block function create | Block function update | 
| --- | --- | --- | --- | --- | --- | 
|  OS-only Runtime  |  `provided.al2023`  |  Amazon Linux 2023  |   Jun 30, 2029   |   Jul 31, 2029   |   Aug 31, 2029   | 
|  OS-only Runtime  |  `provided.al2`  |  Amazon Linux 2  |   Jul 31, 2026   |   Aug 31, 2026   |   Sep 30, 2026   | 

The Amazon Linux 2023 (`provided.al2023`) runtime provides several advantages over Amazon Linux 2, including a smaller deployment footprint and updated versions of libraries such as `glibc`.

The `provided.al2023` runtime uses `dnf` as the package manager instead of `yum`, which is the default package manager in Amazon Linux 2. For more information about the differences between `provided.al2023` and `provided.al2`, see [Introducing the Amazon Linux 2023 runtime for Amazon Lambda](https://amazonaws-china.com/blogs/compute/introducing-the-amazon-linux-2023-runtime-for-aws-lambda/) on the Amazon Compute Blog.