diff --git a/.envrc b/.envrc
new file mode 100644
index 0000000..4898c86
--- /dev/null
+++ b/.envrc
@@ -0,0 +1,5 @@
+if ! has nix_direnv_version || ! nix_direnv_version 2.2.0; then
+    source_url "https://raw.githubusercontent.com/nix-community/nix-direnv/2.2.0/direnvrc" "sha256-5EwyKnkJNQeXrRkYbwwRBcXbibosCJqyIUuz9Xq+LRc="
+fi
+nix_direnv_watch_file ./shell/default.nix flake.lock
+use flake -L
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ff51edf
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+.direnv
\ No newline at end of file
diff --git a/README.md b/README.md
index e35bb0e..0e198b5 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,17 @@
 # cardano.nix
+
+Collection of Cardano related NixOS modules, with a special focus on:
+
+- autogenerated documentation
+- comprehensive (NixOS) tests
+- an homogeneous module interface
+
+## Shell
+
+`cardano.nix` provides a shell that includes some useful aliases:
+
+- `fmt` formats the entire repository using [treefmt](https://github.com/numtide/treefmt)
+- `build-all` builds all the flake's outputs using [devour-flake](https://github.com/srid/devour-flake)
+- `check` simply stands for `nix flake check`
+
+A `.envrc` is also provided, using [direnv]() and [nix-direnv](https://github.com/nix-community/nix-direnv) is highly suggested.
diff --git a/checks/default.nix b/checks/default.nix
new file mode 100644
index 0000000..7e198b6
--- /dev/null
+++ b/checks/default.nix
@@ -0,0 +1,38 @@
+{inputs, ...}: {
+  perSystem = {
+    pkgs,
+    config,
+    ...
+  }: {
+    apps = {
+      nix-build-all.program = pkgs.writeShellApplication {
+        name = "nix-build-all";
+        runtimeInputs = [
+          (pkgs.callPackage inputs.devour-flake {})
+        ];
+        text = ''
+          # Make sure that flake.lock is sync
+          nix flake lock --no-update-lock-file
+
+          # Do a full nix build (all outputs)
+          devour-flake . "$@"
+        '';
+      };
+    };
+
+    devshells.default.commands = [
+      {
+        category = "Tools";
+        name = "build-all";
+        help = "Build all the checks";
+        command = config.apps.nix-build-all.program;
+      }
+      {
+        category = "Tools";
+        name = "check";
+        help = "Alias of `nix flake check`";
+        command = "nix flake check";
+      }
+    ];
+  };
+}
diff --git a/ci/default.nix b/ci/default.nix
new file mode 100644
index 0000000..43be2f5
--- /dev/null
+++ b/ci/default.nix
@@ -0,0 +1,6 @@
+{inputs, ...}: {
+  imports = [
+    inputs.hercules-ci-effects.flakeModule
+  ];
+  config.herculesCI.ciSystems = ["x86_64-linux" "x86_64-darwin"];
+}
diff --git a/flake.lock b/flake.lock
new file mode 100644
index 0000000..3a55c3c
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,299 @@
+{
+  "nodes": {
+    "devour-flake": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1694098737,
+        "narHash": "sha256-O51F4YFOzlaQAc9b6xjkAqpvrvCtw/Os2M7TU0y4SKQ=",
+        "owner": "srid",
+        "repo": "devour-flake",
+        "rev": "30a34036b29b0d12989ef6c8be77aa949d85aef5",
+        "type": "github"
+      },
+      "original": {
+        "owner": "srid",
+        "repo": "devour-flake",
+        "type": "github"
+      }
+    },
+    "devshell": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ],
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1695973661,
+        "narHash": "sha256-BP2H4c42GThPIhERtTpV1yCtwQHYHEKdRu7pjrmQAwo=",
+        "owner": "numtide",
+        "repo": "devshell",
+        "rev": "cd4e2fda3150dd2f689caeac07b7f47df5197c31",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "devshell",
+        "type": "github"
+      }
+    },
+    "flake-parts": {
+      "inputs": {
+        "nixpkgs-lib": "nixpkgs-lib"
+      },
+      "locked": {
+        "lastModified": 1696343447,
+        "narHash": "sha256-B2xAZKLkkeRFG5XcHHSXXcP7To9Xzr59KXeZiRf4vdQ=",
+        "owner": "hercules-ci",
+        "repo": "flake-parts",
+        "rev": "c9afaba3dfa4085dbd2ccb38dfade5141e33d9d4",
+        "type": "github"
+      },
+      "original": {
+        "owner": "hercules-ci",
+        "repo": "flake-parts",
+        "type": "github"
+      }
+    },
+    "flake-parts_2": {
+      "inputs": {
+        "nixpkgs-lib": "nixpkgs-lib_2"
+      },
+      "locked": {
+        "lastModified": 1688466019,
+        "narHash": "sha256-VeM2akYrBYMsb4W/MmBo1zmaMfgbL4cH3Pu8PGyIwJ0=",
+        "owner": "hercules-ci",
+        "repo": "flake-parts",
+        "rev": "8e8d955c22df93dbe24f19ea04f47a74adbdc5ec",
+        "type": "github"
+      },
+      "original": {
+        "id": "flake-parts",
+        "type": "indirect"
+      }
+    },
+    "flake-parts_3": {
+      "inputs": {
+        "nixpkgs-lib": [
+          "hercules-ci-effects",
+          "hercules-ci-agent",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1688466019,
+        "narHash": "sha256-VeM2akYrBYMsb4W/MmBo1zmaMfgbL4cH3Pu8PGyIwJ0=",
+        "owner": "hercules-ci",
+        "repo": "flake-parts",
+        "rev": "8e8d955c22df93dbe24f19ea04f47a74adbdc5ec",
+        "type": "github"
+      },
+      "original": {
+        "owner": "hercules-ci",
+        "repo": "flake-parts",
+        "type": "github"
+      }
+    },
+    "flake-root": {
+      "locked": {
+        "lastModified": 1692742795,
+        "narHash": "sha256-f+Y0YhVCIJ06LemO+3Xx00lIcqQxSKJHXT/yk1RTKxw=",
+        "owner": "srid",
+        "repo": "flake-root",
+        "rev": "d9a70d9c7a5fd7f3258ccf48da9335e9b47c3937",
+        "type": "github"
+      },
+      "original": {
+        "owner": "srid",
+        "repo": "flake-root",
+        "type": "github"
+      }
+    },
+    "haskell-flake": {
+      "locked": {
+        "lastModified": 1684780604,
+        "narHash": "sha256-2uMZsewmRn7rRtAnnQNw1lj0uZBMh4m6Cs/7dV5YF08=",
+        "owner": "srid",
+        "repo": "haskell-flake",
+        "rev": "74210fa80a49f1b6f67223debdbf1494596ff9f2",
+        "type": "github"
+      },
+      "original": {
+        "owner": "srid",
+        "ref": "0.3.0",
+        "repo": "haskell-flake",
+        "type": "github"
+      }
+    },
+    "hercules-ci-agent": {
+      "inputs": {
+        "flake-parts": "flake-parts_3",
+        "haskell-flake": "haskell-flake",
+        "nixpkgs": "nixpkgs"
+      },
+      "locked": {
+        "lastModified": 1688568579,
+        "narHash": "sha256-ON0M56wtY/TIIGPkXDlJboAmuYwc73Hi8X9iJGtxOhM=",
+        "owner": "hercules-ci",
+        "repo": "hercules-ci-agent",
+        "rev": "367dd8cd649b57009a6502e878005a1e54ad78c5",
+        "type": "github"
+      },
+      "original": {
+        "id": "hercules-ci-agent",
+        "type": "indirect"
+      }
+    },
+    "hercules-ci-effects": {
+      "inputs": {
+        "flake-parts": "flake-parts_2",
+        "hercules-ci-agent": "hercules-ci-agent",
+        "nixpkgs": "nixpkgs_2"
+      },
+      "locked": {
+        "lastModified": 1697031886,
+        "narHash": "sha256-oTMPX8dGC7yxSwrbF4NuPNQsUEcHB1dusW2yEbFD5zg=",
+        "owner": "hercules-ci",
+        "repo": "hercules-ci-effects",
+        "rev": "178b36dc3a75c96efc25477d45eafc37ba1fafc3",
+        "type": "github"
+      },
+      "original": {
+        "owner": "hercules-ci",
+        "repo": "hercules-ci-effects",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1688322751,
+        "narHash": "sha256-eW62dC5f33oKZL7VWlomttbUnOTHrAbte9yNUNW8rbk=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "0fbe93c5a7cac99f90b60bdf5f149383daaa615f",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs-lib": {
+      "locked": {
+        "dir": "lib",
+        "lastModified": 1696019113,
+        "narHash": "sha256-X3+DKYWJm93DRSdC5M6K5hLqzSya9BjibtBsuARoPco=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "f5892ddac112a1e9b3612c39af1b72987ee5783a",
+        "type": "github"
+      },
+      "original": {
+        "dir": "lib",
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs-lib_2": {
+      "locked": {
+        "dir": "lib",
+        "lastModified": 1688049487,
+        "narHash": "sha256-100g4iaKC9MalDjUW9iN6Jl/OocTDtXdeAj7pEGIRh4=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "4bc72cae107788bf3f24f30db2e2f685c9298dc9",
+        "type": "github"
+      },
+      "original": {
+        "dir": "lib",
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_2": {
+      "locked": {
+        "lastModified": 1689393711,
+        "narHash": "sha256-l3gyTPy/qWLDk1CY1EgYwlsxcGxN2aVd7MlCzQa69rk=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "27fcd46fa18df36d270174246e7bd8f1787129ff",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_3": {
+      "locked": {
+        "lastModified": 1697059129,
+        "narHash": "sha256-9NJcFF9CEYPvHJ5ckE8kvINvI84SZZ87PvqMbH6pro0=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "5e4c2ada4fcd54b99d56d7bd62f384511a7e2593",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "devour-flake": "devour-flake",
+        "devshell": "devshell",
+        "flake-parts": "flake-parts",
+        "flake-root": "flake-root",
+        "hercules-ci-effects": "hercules-ci-effects",
+        "nixpkgs": "nixpkgs_3",
+        "treefmt-nix": "treefmt-nix"
+      }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    },
+    "treefmt-nix": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1697388351,
+        "narHash": "sha256-63N2eBpKaziIy4R44vjpUu8Nz5fCJY7okKrkixvDQmY=",
+        "owner": "numtide",
+        "repo": "treefmt-nix",
+        "rev": "aae39f64f5ecbe89792d05eacea5cb241891292a",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "treefmt-nix",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 0000000..05cb35c
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,44 @@
+{
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    flake-parts.url = "github:hercules-ci/flake-parts";
+
+    # we use effects for CI and documentation
+    hercules-ci-effects.url = "github:hercules-ci/hercules-ci-effects";
+
+    # Utilities
+    devshell = {
+      url = "github:numtide/devshell";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+    flake-root.url = "github:srid/flake-root";
+    treefmt-nix = {
+      url = "github:numtide/treefmt-nix";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+    devour-flake = {
+      url = "github:srid/devour-flake";
+      flake = false;
+    };
+  };
+  outputs = inputs @ {flake-parts, ...}:
+    flake-parts.lib.mkFlake {
+      inherit inputs;
+    }
+    {
+      imports = [
+        ./lib
+        ./checks
+        ./ci
+        ./formatter
+        ./modules
+        ./shell
+      ];
+      systems = [
+        "x86_64-linux"
+        "aarch64-linux"
+        "x86_64-darwin"
+        "aarch64-darwin"
+      ];
+    };
+}
diff --git a/formatter/default.nix b/formatter/default.nix
new file mode 100644
index 0000000..c3aef65
--- /dev/null
+++ b/formatter/default.nix
@@ -0,0 +1,35 @@
+{inputs, ...}: {
+  imports = [
+    inputs.flake-root.flakeModule
+    inputs.treefmt-nix.flakeModule
+  ];
+
+  perSystem = {
+    config,
+    pkgs,
+    lib,
+    ...
+  }: {
+    treefmt.config = {
+      inherit (config.flake-root) projectRootFile;
+      package = pkgs.treefmt;
+      flakeFormatter = true;
+      flakeCheck = true;
+      programs = {
+        alejandra.enable = true;
+        deadnix.enable = true;
+        prettier.enable = true;
+        statix.enable = true;
+      };
+    };
+
+    devshells.default.commands = [
+      {
+        category = "Tools";
+        name = "fmt";
+        help = "Format the source tree";
+        command = lib.getExe config.treefmt.build.wrapper;
+      }
+    ];
+  };
+}
diff --git a/lib/default.nix b/lib/default.nix
new file mode 100644
index 0000000..c8d977e
--- /dev/null
+++ b/lib/default.nix
@@ -0,0 +1,5 @@
+{lib, ...}: let
+  lib' = import ./functions.nix lib;
+in {
+  flake.lib = lib';
+}
diff --git a/lib/functions.nix b/lib/functions.nix
new file mode 100644
index 0000000..34dca26
--- /dev/null
+++ b/lib/functions.nix
@@ -0,0 +1,2 @@
+_lib: rec {
+}
diff --git a/modules/cardano-cli/default.nix b/modules/cardano-cli/default.nix
new file mode 100644
index 0000000..e6c72de
--- /dev/null
+++ b/modules/cardano-cli/default.nix
@@ -0,0 +1,15 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+with lib; {
+  options.cardano-ecosystem.cli.enable = mkEnableOption "Install cardano CLI tools and scripts";
+
+  config = mkIf config.cardano-ecosystem.cli.enable {
+    environment.systemPackages = with pkgs; [
+      git # FIXME: just a placeholder
+    ];
+  };
+}
diff --git a/modules/default.nix b/modules/default.nix
new file mode 100644
index 0000000..a70814e
--- /dev/null
+++ b/modules/default.nix
@@ -0,0 +1,13 @@
+{
+  imports = [
+  ];
+
+  flake.nixosModules = {
+    global = ./global;
+    cardano-cli = ./cardano-cli;
+    # the default module imports all modules
+    default = {
+      imports = with builtins; attrValues (removeAttrs config.flake.nixosModules ["default"]);
+    };
+  };
+}
diff --git a/modules/global/default.nix b/modules/global/default.nix
new file mode 100644
index 0000000..7aed610
--- /dev/null
+++ b/modules/global/default.nix
@@ -0,0 +1,41 @@
+{
+  lib,
+  config,
+  ...
+}: let
+  cfg = config.cardano-ecosystem.globals;
+in
+  # FIXME: proper assertion, private also can have any unused number
+  #  assert cfg.networkNumbers ? cfg.network;
+  with lib; {
+    options.cardano-ecosystem.globals = {
+      network = mkOption {
+        type = types.enum (builtins.attrNames networkNumbers);
+        default = "mainnet";
+        description = ''
+          Cardano network to join/use
+        '';
+      };
+      networkNumber = mkOption {
+        type = types.int;
+        default = networkNumbers.${cfg.network};
+        description = ''
+          Cardano network number to join/use (should match cardano-ecosystem.globals,network)
+        '';
+      };
+      networkNumbers = mkOption {
+        type = types.attrsOf types.int;
+        # FIXME: fill other nets
+        # FIXME: could we extract networkNumbers automatically?
+        # FIXME: could we extract it from IOG nix stuff w/o IFD or massive inclusion of https://github.com/input-output-hk/iohk-nix
+        default = {
+          mainnet = 0;
+          preprod = 1;
+          preview = 2;
+          sanchonet = 4;
+          private = 42;
+        };
+        internal = true;
+      };
+    };
+  }
diff --git a/shell/default.nix b/shell/default.nix
new file mode 100644
index 0000000..d9584e9
--- /dev/null
+++ b/shell/default.nix
@@ -0,0 +1,25 @@
+{inputs, ...}: {
+  imports = [
+    inputs.devshell.flakeModule
+  ];
+
+  perSystem = {
+    pkgs,
+    config,
+    ...
+  }: {
+    devshells.default = {
+      devshell = {
+        name = "cardano.nix";
+        motd = ''
+          ❄️ Welcome to the {14}{bold}cardano.nix{reset}'s shell ❄️
+          $(type -p menu &>/dev/null && menu)
+        '';
+      };
+      packages = with pkgs; [
+        statix
+        config.treefmt.build.wrapper
+      ];
+    };
+  };
+}