Add "Nix for PHP Developers" talk

source/_pages/presentations.html.twig

@@ -14,6 +14,10 @@ use: [presentations]
       </h2>
     </div>
 
-    <p>{{ presentation.description }}</p>
+    {% if presentation.blocks.description %}
+      {{ presentation.blocks.description|raw }}
+    {% else %}
+      <p>{{ presentation.description }}</p>
+    {% endif %}
   </article>
 {% endfor %}

source/_presentations/nix-for-php-developers.md

@@ -0,0 +1,18 @@
+---
+title: Nix for PHP Developers
+events:
+  - name: PHP Thames Valley
+    location: Reading, UK
+    date: 2025-08-20
+    url: https://www.eventbrite.co.uk/e/php-thames-valley-oxfordshire-and-berkshire-3-x-speakers-networking-tickets-1512713198899
+---
+
+{% block description %}
+How PHP Developers can use Nix in their projects to create robust and reproducible environments and replace tools like Docker and Vagrant.
+{% endblock %}
+
+{% block abstract %}
+[Nix](https://nixos.org) is a package manager with more than 120,000 packages, an operating system with more than 20,000 options, and a build tool for creating reproducible and reliable software that works the same for everyone, every time.
+
+In this talk, Oliver will explain what Nix is, show how to create development shells for PHP that mean you no longer need to use containers or virtual machines, and how to package PHP applications that are easy to deploy and distribute.
+{% endblock %}