diff --git a/nix.md b/nix.md
index ad740b6..8872830 100644
--- a/nix.md
+++ b/nix.md
@@ -27,6 +27,11 @@ newlines"
 ```
 <div class="eval">= true</div>
 
+```nix
+''alternative syntax''
+```
+<div class="eval">= "alternative syntax"</div>
+
 Nix has booleans.
 
 ```nix
@@ -123,14 +128,14 @@ using the repl, press <kbd>tab</kbd> to get a list of them.
 ```
 <div class="eval">= { system = "x86_64-linux"; }</div>
 
-Finally, nix has a path type. When 
+Finally, nix has a path type.
 
 ```nix
 {
   sourceCode = ./path/to/sources;
 }
 ```
-<div class="eval">= { system = "x86_64-linux"; }</div>
+<div class="eval">= { sourceCode = /absolute/path/to/sources; }</div>
 :::
 
 ::: section
@@ -156,10 +161,13 @@ derivation {
   system = builtins.currentSystem;
 }
 ```
-<div class="eval">= derivation «/nix/store/ha5hof1nput-foobar.drv»</div>
+<div class="eval">= derivation «/nix/store/119h84n7a58069l5zi0rgs7q06rhrlh3-foobar.drv»</div>
 
-To build this, use `:b (copy-pasted code)` in the repl. It should print
-a path to the build outputs.
+This code outputs a hash-based path to a derivation, nix's version of a
+build script. Derivations *derive* build outputs from build inputs. To
+build the derivation, use `:b (copy-pasted code)` in the repl. It should
+print a path to the build outputs. If you `cat` the output, you should
+get back "Hello, derivation!".
 
 [NixOS/nixpkgs](https://github.com/NixOS/nixpkgs) is a combination package
 repository and standard library, containing thousands of derivations and
@@ -178,24 +186,24 @@ will *always* produce the same outputs. If it works on one nix user's
 machine, it will work every nix user's machine. If a build fails, it
 fails for everyone.
 
-Flakes work by taking in an explicit set of inputs along with the build
-steps. Anything that isn't explicitly defined as an input, whether
-it's binaries, paths, or environment variables, is not given to the
-derivation's builder.
-
-Here's an example flake:
+Nix flakes are a new tool that makes the inputs explicit as well, instead
+of only the build steps. Anything that isn't explicitly defined as an
+input, whether it's binaries, paths, or environment variables, is not
+given to the derivation's builder.  Here's an example flake:
 
 ```nix
 {
   description = "any useful description here";
 
   inputs = {
-    # this is a flake identifier
+    # Inputs take in flake references
+    # https://nix.dev/manual/nix/2.18/command-ref/new-cli/nix3-flake#flake-references
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
   outputs = { self, nixpkgs }: {
-    packages.x86_64-linux.default = inputs.nixpkgs.legacyPackages.x86_64-linux.hello;
+    # reuse an existing derivation for simplicity
+    packages.x86_64-linux.default = nixpkgs.legacyPackages.x86_64-linux.hello;
   };
 }
 ```
@@ -222,8 +230,14 @@ another flake:
     packages.x86_64-linux.default = pkgs.stdenv.mkDerivation {
       name = "hello";
       src = self;
-      buildPhase = "echo '#!/bin/sh\necho hello world' > bin; chmod +x bin";
-      installPhase = "mkdir -p $out/bin; mv bin $out/bin/hello";
+      buildPhase = ''
+        echo -e '#!/bin/sh\necho hello world' > bin
+        chmod +x bin
+      '';
+      installPhase = ''
+        mkdir -p $out/bin
+        mv bin $out/bin/hello
+      '';
     };
   };
 }