From c820094633ef251d497969d9a603aa2b3d50b1da Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Amy=20de=20Buitl=C3=A9ir?= <amy@nualeargais.ie>
Date: Mon, 12 Jun 2023 18:32:56 +0100
Subject: [PATCH] clean up afterward

---
 source/hello-flake-repo.adoc0   | 80 +++++++++++++++++++++++++++++++++
 source/modify-hello-flake.adoc0 |  3 +-
 source/python-flake.adoc0       |  2 +-
 3 files changed, 83 insertions(+), 2 deletions(-)
 create mode 100644 source/hello-flake-repo.adoc0

diff --git a/source/hello-flake-repo.adoc0 b/source/hello-flake-repo.adoc0
new file mode 100644
index 0000000..5eb2206
--- /dev/null
+++ b/source/hello-flake-repo.adoc0
@@ -0,0 +1,80 @@
+== The hello-flake repo
+
+Let’s clone the repository and see how the flake is defined.
+
+....
+$ git clone https://codeberg.org/mhwombat/hello-flake
+$ cd hello-flake
+$ ls
+....
+
+This is a simple repo with just a few files. Like most git repos, it
+includes `LICENSE`, which contains the software license, and `README.md`
+which provides information about the repo.
+
+The `hello-flake` file is the command we were executing earlier. This
+particular executable is just a shell script, so we can view it. It’s an
+extremly simple script with just two lines.
+
+....
+$ cat hello-flake
+....
+
+Now that we have a copy of the repo, we can execute this script
+directly.
+
+....
+$ ./hello-flake
+....
+
+Not terribly exciting, I know. But starting with such a simple package
+makes it easier to focus on the flake system without getting bogged down
+in the details. We’ll make this script a little more interesting later.
+
+Let’s look at another file. The file that defines how to package a flake
+is always called `flake.nix`.
+
+....
+$ cat flake.nix
+....
+
+If this is your first time seeing a flake definition, it probably looks
+intimidating. Flakes are written in a functional language called
+Nixfootnote:[For an introduction to the Nix language, see
+https://nixos.org/guides/nix-language.html[Nix language basics].]. Yes,
+``Nix'' is the name of both the package manager and the language it
+uses. We’ll look at this in more detail shortly. For now, I’d like to
+focus on the inputs section.
+
+....
+inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+....
+
+There are just two entries, one for `nixpkgs` and one for `flake-utils`.
+The first one, `nixpkgs` refers to the collection of standard software
+packages that can be installed with the Nix package manager. The second,
+`flake-utils`, is a collection of utilities that simplify writing
+flakes. The important thing to note is that the `hello-flake` package
+_depends_ on `nixpkgs` and `flake-utils`.
+
+Finally, let’s look at `flake.lock`, or rather, just part of it.
+
+....
+$ head -n 40 flake.lock
+$# cd .. ; rm -rf hello-flake # clean up
+....
+
+If `flake.nix` seemed intimidating, then this file looks like an
+invocation for Cthulhu. The good news is that this file is automatically
+generated; you never need to write it. It contains information about all
+of the dependencies for the flake, including where they came from, the
+exact version/revision, and hash. This lockfile _uniquely_ specifies all
+flake dependencies, (e.g., version number, branch, revision, hash), so
+that _anyone, anywhere, any time, can re-create the exact same
+environment that the original developer used._
+
+No more complaints of ``but it works on my machine!''. That is the
+benefit of using flakes.
diff --git a/source/modify-hello-flake.adoc0 b/source/modify-hello-flake.adoc0
index ef9747e..2c10438 100644
--- a/source/modify-hello-flake.adoc0
+++ b/source/modify-hello-flake.adoc0
@@ -6,7 +6,8 @@ opportunity to check your understanding of flakes.
 The first step is to enter a development shell.
 
 ....
-$ cd ~/tutorial-practice/hello-flake
+$# git clone https://codeberg.org/mhwombat/hello-flake
+$# cd hello-flake
 $ nix develop
 ....
 
diff --git a/source/python-flake.adoc0 b/source/python-flake.adoc0
index a42867e..fe52d80 100644
--- a/source/python-flake.adoc0
+++ b/source/python-flake.adoc0
@@ -4,7 +4,6 @@ At last we are ready to create a flake from scratch! Start with an empty
 directory and create a git repository.
 
 ....
-$ cd ~/tutorial-practice
 $ mkdir hello-python
 $ cd hello-python
 $ git init
@@ -180,6 +179,7 @@ another directory and running it from there.
 ....
 $ cd ~
 $ nix run ~/tutorial-practice/hello-python
+$# cd .. ; rm -rf hello-python # clean up
 ....
 
 If you move the project to a public repo, anyone can run it. Recall from