how install mavenix ? (config.nix)

[PlumpHip]

hello.

mavenix = pkgs.callPackage (fetchTarball { url = "https://github.com/icetan/mavenix/archive/v2.3.3.tar.gz"; sha256 = "1l653ac3ka4apm7s4qrbm4kx7ij7n2zk3b67p9l0nki8vxxi8jv7"; }) { inherit pkgs; }; and packages install to [ mavenix ];

but error: error: while evaluating the attribute 'passAsFile' of the derivation 'pnix' at /nix/store/vj3xx6gxif8cjj97w0y08w81ys09avg9-nixpkgs-20.03pre216072.a26e92a67d8/nixpkgs/pkgs/build-support/trivial-builders.nix:7:14: cannot convert a function to JSON

Help me~* Thanks.

[PlumpHip]

I solve mavenix.cli thanks~*