I'm trying to install ncdu using MacPorts in macOS Catalina, however it depends on zig but zig is no longer compatible, looking for workaround

I have an old MacBook which cannot be upgraded to anything higher than Catalina (at least officially) and I had been using Homebrew but since now it's not supported it tries to compile every package and that takes a very long time, so I switched to MacPorts. I'm trying to install the ncdu port but it depends on zig, MacPorts fetches zig-0.11.0_0.darwin_19.x86_64 but the build fails with error: command execution failed. I checked here https://ports.macports.org/port/zig/details/ and noticed that indeed it doesn't work with Catalina because it requires darwin >= 20. I manually downloaded zig 0.10.1 and it works fine so my question is: Is there a way to make MacPorts use the zig version that I installed manually and take that one as a dependency for installing ncdu (a previous version if possible). It's my first time using MacPorts so any help is really appreciated, thanks.