I recommend to have a look at Mill. It's versatile, built on simple foundations, and implements many concepts from general-purpose build tools such as Bazel (but of course it was designed for Scala). It's easy to call it from various scripts too, and doesn't require you to design your project around your build tool.

At work we've used mill to first replace sbt and then also gradle in another project, and haven't looked back. It worked out-of-the-box for our JVM projects, and we trivially wrote custom "rules" for integrating cmake-based C++ projects into the build.