what's new in swift 6.2

In Swift 6.2, several new features and improvements have been introduced to enhance the productivity and capabilities of Swift developers. Here are some of the key updates:

1. Strict Memory Safety: A new feature called Strict Memory Safety requires explicit acknowledgment of unsafe API usage in the source code. This helps identify parts of the code that need extra security attention. This feature is being adopted in security-critical components like WebKit and a subsystem of the Messages app.

2. Concurrency Improvements: Swift 6.2 changes the default behavior to stay single-threaded until concurrency is explicitly introduced. This makes the most natural code data race-free by default, providing a more approachable path to introducing concurrency.

3. Performance Enhancements: The release includes performance updates such as inline arrays, which allow arrays with a fixed size to be stored on the stack, enabling significant performance optimizations. A new span type provides a safe alternative to pointers for fast, direct access to contiguous memory.

4. Development Workflow Improvements: Enhancements have been made to the development workflow, including improvements in writing, building, and debugging code. The Swift extension in VS Code is now officially verified and distributed by Swift.org, with features like background indexing enabled by default.

5. Core Libraries Updates: Swift 6.2 modernizes more of Foundation's API surface and introduces new APIs to streamline everyday programming tasks. A new package with APIs for launching subprocesses has been introduced to improve scripting tasks.

6. Embedded Swift: Swift 6.2 expands Embedded Swift, a subset of Swift for writing code targeting constrained environments like firmware for embedded devices.

7. C Interoperability: Improvements have been made to C interoperability, allowing C pointers annotated with length and lifetime information to be bridged into Swift as a span, providing a memory-safe interface.

For more detailed information, you can watch the session What’s new in Swift (00:00:00) from WWDC 2025.