Nix Flakes development headers

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1

Hey,

I’m currently trying to build ns-3 with the module 5G Lena inside.’
I use NixOS as an Operating system and use flakes.
I know that development headers for libraries i need (Notably sqlite and eigen) don’t come when installing these packages.

For that I Would need to add the packages somehow to my flake for my dev shell to use nix develop.
I’m very new to NixOS and try to figure these things out step by step, but feel a bit lost on how to get this done.

My flake.nix is looking like this (GitHub Link: GitHub - NoelHuibers/.dotfiles):

{
description = “Nixos config flake”;

inputs = {
nixpkgs.url = “github:nixos/nixpkgs/nixos-unstable”;

home-manager = {
  url = "github:nix-community/home-manager";
  inputs.nixpkgs.follows = "nixpkgs";
};

};

outputs =
{ self, nixpkgs, … }@inputs:
let
system = “x86_64-linux”;
pkgs = import nixpkgs {
inherit system;
config = {
allowUnfree = true;
};
};
in
{
nixosConfigurations = {
default = nixpkgs.lib.nixosSystem {
specialArgs = {
inherit inputs system;
};
modules = [
./hosts/default/configuration.nix
];
};
};
};
}

If you need any more information let me know.