From 18597260bf4e1e7a4993db913e4d667502038317 Mon Sep 17 00:00:00 2001
From: Daniel Flanagan <daniel@lyte.dev>
Date: Mon, 8 Jul 2024 12:18:24 -0500
Subject: [PATCH] Nix copy done

---
 flake.nix | 17 ++++++++++--
 post.md   | 78 ++++++++++++++++++++++++++++++++++---------------------
 2 files changed, 63 insertions(+), 32 deletions(-)

diff --git a/flake.nix b/flake.nix
index 2a99357..99d6d52 100644
--- a/flake.nix
+++ b/flake.nix
@@ -1,11 +1,24 @@
 {
   inputs.nixpkgs.url = "nixpkgs/nixos-24.05";
-  outputs = {nixpkgs, ...}: let
+  outputs = {
+    self,
+    nixpkgs,
+    ...
+  }: let
     systems = ["aarch64-linux" "aarch64-darwin" "x86_64-darwin" "x86_64-linux"];
     pkgsFor = func: (nixpkgs.lib.genAttrs systems (system: (func (import nixpkgs {inherit system;}))));
   in {
     packages = pkgsFor (pkgs: {
-      what-is-my-ip = pkgs.callPackage ./what-is-my-ip.nix {};
+      default = pkgs.callPackage ./what-is-my-ip.nix {};
+    });
+
+    devShells = pkgsFor (pkgs: {
+      default = pkgs.mkShell {
+        packages = [self.outputs.packages.${pkgs.system}.default];
+        shellHook = ''
+          echo "Hello, Nix!"
+        '';
+      };
     });
   };
 }
diff --git a/post.md b/post.md
index 1d61b49..5316082 100644
--- a/post.md
+++ b/post.md
@@ -11,9 +11,9 @@ it's pretty fantastic.
 Let's walk through a single example of a shell script one may write: _what-is-my-ip_
 
 ```bash
-#! /usr/bin/env bash
-curl -s http://httpbin.org/get | \
-    jq --raw-output .origin
+#!/usr/bin/env bash
+curl -s http://httpbin.org/get \
+  | jq --raw-output .origin
 ```
 
 Sure, it's _sort of portable_, if you tell the person running it to have _curl_ and _jq_. What if you relied on a specific version of either though?
@@ -31,7 +31,7 @@ We might leverage _[Nixpkgs' trivial builders](https://ryantm.github.io/nixpkgs/
     pkgsFor = func: (nixpkgs.lib.genAttrs systems (system: (func (import nixpkgs {inherit system;}))));
   in {
     packages = pkgsFor (pkgs: {
-      what-is-my-ip = pkgs.callPackage ./what-is-my-ip.nix {};
+      default = pkgs.callPackage ./what-is-my-ip.nix {};
     });
   };
 }
@@ -50,21 +50,21 @@ pkgs.writeShellScriptBin "what-is-my-ip" ''
 
 Here we are pinning our package to dependencies which come from NixOS/Nixpkgs release branch 24.05.
 
-If we `nix build .#what-is-my-ip` and `readlink result` we get:
+If we `nix build` and `readlink result` we get:
 
   **/nix/store/lr6wlz2652r35rwzc79samg77l6iqmii-what-is-my-ip**
 
-And, of course, we can run our result:
+And, of course, we can run our built result:
 
-```bash
+```console
 $ ./result/bin/what-is-my-ip 
 24.5.113.148
 ```
 
-Or run it from the Flake:
+Or run it from the Flake directly:
 
-```bash
-$ nix run .#what-is-my-ip
+```console
+$ nix run
 24.5.113.148
 ```
 
@@ -77,26 +77,46 @@ $ nix-store --query --graph $(readlink result) | nix shell nixpkgs#graphviz -c d
 [![Image of what-is-my-ip dependencies as a graph](/assets/images/what-is-my-ip-deps.png)](/assets/images/what-is-my-ip-deps.png)
 
 Let's create a _developer environment_ and bring in our new tool.
-This is a great way to create developer environment with reproducible tools
+This is a great way to create developer environments with reproducible tools.
 
-```nix
-let
-  pkgs = import (fetchTarball "https://github.com/NixOS/nixpkgs/archive/nixos-24.05.tar.gz") {};
-  what-is-my-ip = import ./what-is-my-ip.nix {inherit pkgs;};
-in
-  pkgs.mkShell {
-    packages = [what-is-my-ip];
-    shellHook = ''
-      echo "Hello, Nix!"
-    '';
-  }
+```diff
+diff --git a/flake.nix b/flake.nix
+index 2a99357..ab32421 100644
+--- a/flake.nix
++++ b/flake.nix
+@@ -1,11 +1,24 @@
+ {
+   inputs.nixpkgs.url = "nixpkgs/nixos-24.05";
+-  outputs = {nixpkgs, ...}: let
++  outputs = {
++    self,
++    nixpkgs,
++    ...
++  }: let
+     systems = ["aarch64-linux" "aarch64-darwin" "x86_64-darwin" "x86_64-linux"];
+     pkgsFor = func: (nixpkgs.lib.genAttrs systems (system: (func (import nixpkgs {inherit system;}))));
+   in {
+     packages = pkgsFor (pkgs: {
+       what-is-my-ip = pkgs.callPackage ./what-is-my-ip.nix {};
+     });
++
++    devShells = pkgsFor (pkgs: {
++      default = pkgs.mkShell {
++        packages = [self.outputs.packages.${pkgs.system}.what-is-my-ip];
++        shellHook = ''
++          echo "Hello, Nix!"
++        '';
++      };
++    });
+   };
+ }
 ```
 
-```
-❯ nix-shell what-is-my-ip-shell.nix
+```console
+$ nix develop -c $SHELL
 Hello, Nix!
 
-[nix-shell:~/tutorial]$ which what-is-my-ip
+$ which what-is-my-ip
 /nix/store/lr6wlz2652r35rwzc79samg77l6iqmii-what-is-my-ip/bin/what-is-my-ip
 ```
 
@@ -104,11 +124,9 @@ Hello, Nix!
 
 We can now do binary or source deployments 🚀🛠️📦 since we know the full dependency closure of our tool. We simply copy the necessary _/nix/store_ paths to another machine with Nix installed.
 
-```bash
-❯ nix copy --to ssh://nixie.tail9f4b5.ts.net \
-    $(nix-build what-is-my-ip.nix) --no-check-sigs
-
-❯ ssh nixie.tail9f4b5.ts.net
+```console
+$ nix copy --to ssh://beefcake $(nix build --print-out-paths)
+$ ssh beefcake
 
 [fmzakari@nixie:~]$ /nix/store/lr6wlz2652r35rwzc79samg77l6iqmii-what-is-my-ip/bin/what-is-my-ip
 98.147.178.19