How Rust Achieves Memory Safety Without Sacrificing Performance or Expressiveness

Christian Baghai
6 min readJan 21, 2024

Memory safety is a crucial aspect of software development, as it can prevent many common and dangerous bugs that can compromise the security and performance of applications and systems. However, not all programming languages are designed to ensure memory safety, and some of the most widely used ones, such as C and C++, are notorious for allowing memory errors that can lead to crashes, vulnerabilities, and exploits.

Rust is a relatively new programming language that aims to provide a memory-safe alternative to C and C++, while also offering low-level control, high performance, and concurrency support. Rust achieves memory safety through a novel system of ownership, borrowing, and lifetimes, which are enforced by the compiler at compile time. This system prevents memory errors such as out-of-bounds access, use-after-free, and data races, without requiring a garbage collector or runtime checks. Rust also allows users to write unsafe code when necessary, but only in a restricted and explicit way, making it easier to audit and isolate.

In this opinion piece, I will argue that Rust is a superior choice for memory-safe programming, compared to other languages that either sacrifice performance, flexibility, or expressiveness, or rely on runtime mechanisms that can introduce overhead, unpredictability, or complexity. I will also discuss some of the challenges and limitations of Rust, and how they can be overcome or mitigated.

Why Rust is better than C and C++

C and C++ are the dominant languages for systems programming, as they offer direct access to hardware resources, manual memory management, and low-level abstractions. However, these languages also expose programmers to a wide range of memory errors, such as buffer overflows, dangling pointers, memory leaks, and undefined behavior. These errors can cause crashes, data corruption, or security breaches, and are often hard to detect and fix. According to various reports, memory errors account for a majority of vulnerabilities in software products from companies like Google, Microsoft, and Apple.

Rust is designed to eliminate these memory errors, by enforcing a set of rules and guarantees at compile time. The core concept…