It's a massive red flag that they don't know enough to be useful.
C is great for the things C is great for, however small that range may or may not be now and in the future.
Any other stance is reductive and misleading.
I’ve been writing C since 1991 and I can’t think of anything where I wouldn’t start a new project in some other language. There are many interesting choices of varying maturity in the low-level systems programming space: Zig, Rust, Crystal, D, Swift (if the standard library ever gains support for system-level programming). Even the “better C” subset of C++ will allow you to avoid certain classes of security bugs completely.
I don’t think C is even merely adequate for anything at this point; defaulting to memory safety is table stakes in any domain where C was once dominant.
Rust is exciting and proving itself about as rapidly as such a language could be expected to do. But there are big questions around how all of this plays out in a long-lived project. There's a good argument that C's simplicity is an asset here.
I like Rust a lot and have done some cool stuff with it. I believe the challenges of long-lived projects will be solved. But at the same time, I admit that there are a lot of other factors (including non-trchnical ones). If you pick a language that doesn't last for whatever reason, and you have a couple decades worth of code, the options are grim.
Implementing low-level code that is important enough to prove correct, without going through the additional effort of de novo proving your entire toolchain is correct.
If I use a micro controller to control a string of leds I do not care about security/memory safety. But I do care about being as close to the metal as possible, and being able to understand the compiled code.
But many microcontrollers these days will likely have a TCP/IP stack, perhaps even crypto, even if it is to control a string of LEDs via MQTT or Modbus TCP.
Thankfully returns in digital stores, warranties in consulting projects, lawsuits in business losses and cybersecurity bills are slowly changing that.
There.
Writing readable code. I'm a huge fan of Zig and Rust too but at the end of the day they just aren't C.
