minimal.tf

terraform {
  required_version = "~> 0.13"

  required_providers {
    aws = {
      source = "hashicorp/aws"
      version = "~> 2.65"
    }

  }
}

output

$ terraform init

Initializing the backend...

Initializing provider plugins...
- Finding latest version of hashicorp/aws...

Error: Failed to query available provider packages

Could not retrieve the list of available versions for provider hashicorp/aws:
provider registry.terraform.io/hashicorp/aws was not found in any of the
search locations

- /nix/store/fam6azhh0wlpaxa27rbxkjyqzrla50xn-tf-plugin-env/bin

shell.nix

{ pkgs ? import <nixpkgs> { } }:
pkgs.stdenv.mkDerivation {
    name = "tf";
    buildInputs = with pkgs; [
      awscli
      (terraform_0_13.withPlugins (ps: [
        # This lets us manage our VMs, DNS, etc on AWS.
        ps.aws
      ]))
    ];
}

tf env

$ find /nix/store/fam6azhh0wlpaxa27rbxkjyqzrla50xn-tf-plugin-env/bin/
/nix/store/fam6azhh0wlpaxa27rbxkjyqzrla50xn-tf-plugin-env/bin/
/nix/store/fam6azhh0wlpaxa27rbxkjyqzrla50xn-tf-plugin-env/bin/terraform-provider-aws_v2.65.0