Introducing a Memory-Safe Successor Language in Large C++ Code Bases

This talk examines how Swift’s memory-safe design and C++ interoperability can support gradual adoption in large C++ code bases. It discusses language features, targeted rewrites, and lessons from rolling out a new language across a software ecosystem.

Syllabus

Introduction
Apples predecessor languages
Problems with C
Mitigation
The biggest problem
Uninitialized memory
Initialize local variables
The real problem
Integer overflow
Bounce checks
pointers and local reasoning
pointers follow stricter rules
Can we fix these problems without a new language
Our successful language is Swift
Swift is a successful language
Local variables
Types
Undefined Behavior
Generic Functions
Swift
Swift Exceptions
Concurrency
Data Isolation
Moving This Way
Three Key Ideas
Be Incremental
The Second System Effect
You Never Succeed
Refactor
Moving Forward
Team Psychology