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     <p><span class="puppet-col">Puppet</span> &nbsp;·&nbsp; <span class="ansible-col">Ansible</span> &nbsp;·&nbsp; <span class="tf-col">Terraform</span> — each fights a different battle.</p>
   </section>
 
+  <!-- ─── SLIDE 12 : Terraform intro ──────────────────────────────── -->
+  <section>
+    <h2>🏗️ <span class="tf-col">Terraform</span></h2>
+    <p>Start here. Before you configure a server, you need to have one.</p>
+  </section>
+
+  <!-- ─── SLIDE 13 : Terraform concepts ───────────────────────────── -->
+  <section>
+    <h2>HCL: HashiCorp Configuration Language.</h2>
+    <p>Declarative, human-readable — and pure JSON works too.<br>
+    <code>terraform plan</code> previews &nbsp;·&nbsp; <code>terraform apply</code> creates &nbsp;·&nbsp; <code>terraform destroy</code> removes.</p>
+  </section>
+
+  <!-- ─── SLIDE 14 : Terraform state ──────────────────────────────── -->
+  <section>
+    <h2>Terraform remembers what it built.</h2>
+    <p>The <code>.tfstate</code> file maps code to real-world resources. Store it remotely.<br>
+    Depending on what you manage, it can contain plaintext sensitive values — credentials, tokens, secrets.<br>
+    <em>Handle it with care. Don't feed it to your LLM.</em></p>
+  </section>
+
+  <!-- ─── SLIDE 15 : Terraform providers ──────────────────────────── -->
+  <section>
+    <h2>One tool. Every API.</h2>
+    <p>1000+ providers: AWS, GCP, Azure, Cloudflare, GitHub, Kubernetes…<br>
+    Not just cloud — manage GitHub teams, Datadog monitors, PagerDuty schedules, DNS records.<br>
+    <em>If it has an API, there's a Terraform provider for it.</em></p>
+  </section>
+
+  <!-- ─── SLIDE 16 : Terraform code ───────────────────────────────── -->
+  <section>
+    <p class="filename"># main.tf</p>
+    <pre><code class="language-hcl" data-trim>
+terraform {
+  required_providers {
+    aws = { source = "hashicorp/aws", version = "~> 5.0" }
+  }
+}
+
+provider "aws" { region = "eu-west-3" }
+
+resource "aws_instance" "web" {
+  ami           = "ami-0c55b159cbfafe1f0"
+  instance_type = "t3.micro"
+  tags = { Name = "finistdevs-web" }
+}
+
+output "public_ip" {
+  value = aws_instance.web.public_ip
+}
+    </code></pre>
+  </section>
+
+  <!-- ─── SLIDE 17 : OpenTofu ──────────────────────────────────────── -->
+  <section>
+    <h2>In 2023, HashiCorp changed Terraform's license.</h2>
+    <p>BSL instead of MPL — no longer truly open-source.<br>
+    The community responded: <strong>OpenTofu</strong>, by the OpenTF Foundation, is the open-source fork.<br>
+    <em>Drop-in replacement. Fully compatible. Community-driven.</em></p>
+  </section>
+
 
 </div>
 </div>