Revisiting the state of Rust

According to the Tiobe index, Python is lonely at the top of “most popular programming languages,” with a score of 23 percent. It’s followed by C++ (10 percent), Java (also 10 percent) and C (9 percent). The index tries to gain insight from what people are searching for in search engines, the assumption being that this provides a measure of popularity. As a relatively young language, Rust scores 14th place with a little over 1 percent.

In a concluding summary, Tiobe CEO Paul Jansen writes about Rust that “its steep learning curve will never make it become the lingua franca of the common programmer, unfortunately.” Mentioning a language’s steep learning curve as the barrier to becoming a big success feels slightly dubious from the perspective of how popular C++ is in combination with its complexity at scale. I also think overestimating and emphasizing a learning curve for a language is selling developers short – many companies adopting Rust in production have already shown it’s very manageable.

Unique feat

Over the past years, Rust has established itself as a worthy alternative in the field of production-grade systems programming. It’s successfully demonstrating how a language can be modern, performant and safe at the same time. It steadily releases every six weeks, so there’s always something new there – we’re at v1.85 at the time of writing. New features land when ready and most language or library changes tend to be more piecemeal.

As Rust is growing more mature, its popularity and adoption have been gradually increasing over time. The risk factor to adopt it as a production language of choice has worn off, as can be concluded from many companies reporting about it. Google has been rewriting parts of Android in Rust for improved security, Microsoft is rewriting core Windows libraries in Rust and Amazon has been known to use Rust in its AWS infrastructure for a long time already.

Another unique feat worth mentioning is that Rust is part of the mainline Linux kernel next to C. It must be said that the effort to expand support for Rust across kernel subsystems isn’t without contention, but progress is being made with the blessing of Linus Torvalds. It will be very interesting to see how this experiment will advance.

Happy developers

I’ve been heavily using Rust alongside C++ for the past number of years. One of my main observations is that switching back from Rust to C++ makes me feel as if I’m being flung back into the dark ages of systems software development. This may sound harsh, but honestly, even when using the leading-edge version, C++23, most coding tasks feel painstakingly hard and limited compared to how they would in Rust. In the early days, I would sometimes miss the ability to directly correlate written code to output machine code as can be done in C++, but this is strictly unnecessary in 99 percent of the cases, and modern compilers are much more competent at optimization than humans anyway.

When it comes to the tooling ecosystem and integration, Rust is on another level altogether and much more up to speed with the web development world today. Whereas the C++ language and compiler often fight me to get things right, Rust’s strictness, type system, sane defaults and borrow checker seem to naturally lead me to the right design decisions – contend vs guide. When my Rust code builds successfully and the tests pass, I can leave the project with the ease of mind that the software won’t crash during runtime and the code can’t easily be broken by a colleague. Also, the Rust macro systems and excellent quality package ecosystem with libraries as well as plugin tools for the build system make a big difference in productivity.

These and other aspects make Rust extremely nice to work with. They make developers happy. There’s a reason why the Stack Overflow developer survey shows Rust as the most widely desired programming language for nine years in a row now.

Dividends

Rust is very much fit for production use, even in critical systems requiring safety certifications (for example by using the Ferrocene toolchain). I see its adoption as a logical move to enjoy the benefits of memory safety, high productivity and increased developer happiness already today, rather than waiting until the current set of tools is up to speed with the rest of the world. Add to that the cross-pollination of becoming a better developer in any other programming language by learning a new one.

When it comes to learning in general, I always tend to keep a positive attitude: people are much more capable than we might think. Yes, the learning curve for Rust is steeper than that of most other languages, but it’s so well worth it and pays dividends in the long term. I would take a steep learning curve and more sane and strict language rules and guarantees over a life with software memory safety bugs any day of the week.

In the two-half-day training course “Exploring Rust,” organized by High Tech Institute, Kris van Rens introduces the benefits of the Rust programming language and how to proceed for successful adoption.