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<h1 id="imperative-vs-declarative"><a class="header" href="#imperative-vs-declarative">Imperative vs Declarative</a></h1>
<p>vmctl supports two workflows for managing VMs.</p>
<h2 id="imperative"><a class="header" href="#imperative">Imperative</a></h2>
<p>Use individual commands to create, configure, and manage VMs step by step:</p>
<pre><code class="language-bash">vmctl create --name myvm --image-url https://example.com/image.img --vcpus 2 --memory 2048 --start
vmctl ssh myvm
vmctl stop myvm
vmctl destroy myvm
</code></pre>
<p>This is useful for:</p>
<ul>
<li>Quick one-off VMs</li>
<li>Experimenting with different images</li>
<li>Scripting custom workflows</li>
</ul>
<h2 id="declarative"><a class="header" href="#declarative">Declarative</a></h2>
<p>Define your VMs in a <code>VMFile.kdl</code> and let vmctl converge to the desired state:</p>
<pre><code class="language-kdl">vm "myvm" {
image-url "https://example.com/image.img"
vcpus 2
memory 2048
cloud-init {
hostname "myvm"
}
ssh {
user "ubuntu"
}
provision "shell" {
inline "echo hello"
}
}
</code></pre>
<pre><code class="language-bash">vmctl up # create + start + provision
vmctl down # stop
vmctl reload # destroy + recreate + provision
vmctl provision # re-run provisioners only
</code></pre>
<p>This is useful for:</p>
<ul>
<li>Reproducible development environments</li>
<li>Multi-VM setups</li>
<li>Checked-in VM definitions alongside your project</li>
<li>Complex provisioning workflows</li>
</ul>
<h2 id="when-to-use-which"><a class="header" href="#when-to-use-which">When to Use Which</a></h2>
<div class="table-wrapper"><table><thead><tr><th>Scenario</th><th>Approach</th></tr></thead><tbody>
<tr><td>"I need a quick VM to test something"</td><td>Imperative</td></tr>
<tr><td>"My project needs a build VM with specific packages"</td><td>Declarative</td></tr>
<tr><td>"I want to script VM lifecycle in CI"</td><td>Either, depending on complexity</td></tr>
<tr><td>"Multiple VMs that work together"</td><td>Declarative</td></tr>
</tbody></table>
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