infrastructure as nix code

terranix is a Nix-based infrastructure-as-code tool that combines the providers of Terraform (or OpenTofu) and the lazy, functional configuration of NixOS. terranix works as an alternative to HCL by generating Terraform JSON that can then be applied using the same providers.

Getting started View on GitHub

terranix config.nix

let
  mkSite = { name, region }: {
    resource.digitalocean_droplet.${name} = {
      inherit name region;
      image = "ubuntu-22-04-x64";
      size  = "s-1vcpu-1gb";
    };
    resource.digitalocean_record.${name} = {
      domain = "example.com";
      type   = "A";
      inherit name;
      value  = "\${digitalocean_droplet.${name}.ipv4_address}";
    };
  };
in {
  imports = [
    (mkSite { name = "web-1"; region = "fra1"; })
    (mkSite { name = "web-2"; region = "nyc1"; })
    (mkSite { name = "web-3"; region = "sgp1"; })
  ];
}

HCL main.tf

locals {
  sites = {
    web-1 = "fra1"
    web-2 = "nyc1"
    web-3 = "sgp1"
  }
}

resource "digitalocean_droplet" "site" {
  for_each = local.sites
  name     = each.key
  region   = each.value
  image    = "ubuntu-22-04-x64"
  size     = "s-1vcpu-1gb"
}

resource "digitalocean_record" "site" {
  for_each = local.sites
  domain   = "example.com"
  type     = "A"
  name     = each.key
  value    = digitalocean_droplet.site[each.key].ipv4_address
}

Features

Full Nix language
Use let-bindings, imports, conditionals, and module composition with the same language you already use for NixOS.
NixOS module system
Type-checked configuration with sensible defaults, overrides, and reusable modules.
nixpkgs ecosystem
Tap into fetchgit, fetchurl, writers, and pin Terraform / OpenTofu versions and providers reproducibly.
Documentation generator
Generate JSON or man-page documentation straight from your config.nix module options.