Ultimately, this will be determined by the scope of the project, and depends on whether you count using an existing C library as part of the Zig ecosystem.
If you want Zig libraries that don't call any C/C++ code whatsoever, then you're going to have a hard time (as of 2025). There's not, e.g, something as mature and tested as glfw in pure Zig. There is work being done to make pure Zig libraries for gamedev however, see for example Mach: https://machengine.org/
If you're happy to use C libraries though (as I am), then things are generally fine. Many of the most popular gamedev C/C++ libraries have already had their build systems converted into Zig (e.g. Raylib) and so can easily be added to a project without having to do any work in the build system.
For C libraries that aren't already packaged, or if you want to maintain full control of the build yourself, packaging libraries with the Zig build system isn't too bad, but it's still a lot of work. (E.g. Ghostty maintains its own build files for its packages; as a result there is a lot of Ghostty build system code: https://github.com/ghostty-org/ghostty/tree/main/pkg )
If you want Zig libraries that don't call any C/C++ code whatsoever, then you're going to have a hard time (as of 2025). There's not, e.g, something as mature and tested as glfw in pure Zig. There is work being done to make pure Zig libraries for gamedev however, see for example Mach: https://machengine.org/
If you're happy to use C libraries though (as I am), then things are generally fine. Many of the most popular gamedev C/C++ libraries have already had their build systems converted into Zig (e.g. Raylib) and so can easily be added to a project without having to do any work in the build system.
For C libraries that aren't already packaged, or if you want to maintain full control of the build yourself, packaging libraries with the Zig build system isn't too bad, but it's still a lot of work. (E.g. Ghostty maintains its own build files for its packages; as a result there is a lot of Ghostty build system code: https://github.com/ghostty-org/ghostty/tree/main/pkg )