Linux

It's nicknamed the autohell tools for a reason.

It's neat but most of its functionality is completely useless to most people. The autotools are so old I think they even predate Linux itself, so it's designed for portability between UNIXes of the time, so it checks the compiler's capabilities and supported features and tries to find paths. That also wildly predate package managers, so they were the official way to install things so there was also a need to make sure to check for dependencies, find dependencies, and all that stuff. Nowadays you might as well just want to write a PKGBUILD if you want to install it, or a Dockerfile. Just no need to check for 99% of the stuff the autotools check. Everything it checks for has probably been standard compiler features for at least the last decade, and the package manager can ensure you have the build dependencies present.

Ultimately you eventually end up generating a Makefile via M4 macros through that whole process, so the Makefiles that get generated look as good as any other generated Makefiles from the likes of CMake and Meson. So you might as well just go for your hand written Makefile, and use a better tool when it's time to generate a Makefile.

(If only c++ build systems caught up to Golang lol)

At least it's not node_modules

Meson and CMake are the two major players I've seen along autotools. Are they better? In some respects, yes (especially Meson, imo), in others... not really. For a pet project that only targets two platforms, I'd just stick to handwritten worst-practices Makefile. You will likely have less trouble with that than any of the others, simply because you know it already.

autoconf and stuff like this? Not anymore. Since ~5 years here it's cmake everywhere, Conan, ninja.

Try Meson first, it should support compiling GNU assembly via the C compiler from what I can find. I've been using CMake for years because it is more powerful (finally trying out Meson though for a new project) but in contrary to Meson it is easy to use the wrong way if you don't know what you're doing. Meson is very clean in comparison, and also very easy to get started with. (And both these are absolutely better than autotools)

(If only c++ build systems caught up to Golang lol)

Terrible bait

I use autotools and don't remember having such issues.

I don't use autotools anymore for any of my private projects. It's plain Makefiles for me simple and easy. But I usualy only target Linux.

It doesn't matter if we "people use it in new projects", but rather, we often have to compile stuff that use them. So they need to be around, regardless of how bad they are. Just last week my husband had to compile two emulators that used autotools.

zig build

Are you building a C/C++ project that should run on BSD, Gnu/Linux and other platforms? Then maybe use autotools. All distro tooling will easily be able to handle it.

Are you just building some small project that will never make it into a distro, maybe just use something simpler. Or even just a plain makefile.