Referencing custom derivations

container.nix

{pkgs, ...}:
pkgs.dockerTools.buildImage {
  name = "pivnet";
  tag = "latest";
  created = "now";

  copyToRoot = pkgs.buildEnv {
    name = "image-root";
    pathsToLink = ["/bin"];

    paths = with pkgs; [
      # Common
      busybox
      curlFull
      cacert

      # Tools
      (callPackage ./pivnet.nix {})
    ];
  };

  config = {
    Entrypoint = [
      ""${REFERENCE_HERE}/bin/pivnet"
    ];
    Cmd = [
    ];
    ExposedPorts = {
    };
    Env = [
      "SSL_CERT_FILE=${pkgs.cacert}/etc/ssl/certs/ca-bundle.crt"
    ];
    WorkingDir = "/workdir";
  };
}

pivnet.nix

{pkgs, ...}: let
  pivnet = pkgs.fetchurl {
    name = "pivnet";
    url = "https://github.com/pivotal-cf/pivnet-cli/releases/download/v3.0.1/pivnet-linux-amd64-3.0.1";
    sha256 = "sha256-et44d6fpcyJ8WMrGrjpRrXiBMDh8FmRjaR/gjzd5KPw=";
  };
in
  pkgs.stdenv.mkDerivation {
    name = "pivnet";
    version = "v3.0.1";

    phases = ["installPhase"];

    installPhase = ''
      mkdir --parents $out/bin

      install --verbose ${pivnet} $out/bin/pivnet
    '';

    meta = {
      description = "CLI to interact with Tanzu Network API V2 interface.";
      homepage = "https://github.com/pivotal-cf/pivnet-cli";
      license = "Apache 2.0";
    };
  }

{pkgs, ...}:
let 
  pivnet = callPackage ./pivnet.nix {};
in
pkgs.dockerTools.buildImage {
  name = "pivnet";
  tag = "latest";
  created = "now";

  copyToRoot = pkgs.buildEnv {
    name = "image-root";
    pathsToLink = ["/bin"];

    paths = (with pkgs; [
      busybox
      curlFull
      cacert
    ]) ++ [pivnet];
  };

  config = {
    Entrypoint = [
      "${pivnet}/bin/pivnet"
    ];
    Cmd = [
    ];
    ExposedPorts = {
    };
    Env = [
      "SSL_CERT_FILE=${pkgs.cacert}/etc/ssl/certs/ca-bundle.crt"
    ];
    WorkingDir = "/workdir";
  };
}