SwarmGen + Ghost

Create OG cards and social images automatically on publish

Ghost is a powerful platform for independent publishers and newsletters. Its built-in webhook system makes it easy to trigger external actions on publish — including generating a SwarmGen image for every post. Set it up once and every post you publish automatically gets a branded OG card, a newsletter header, or a social media banner, without touching a design tool.

How to set it up

1
Build your Ghost post template
Create a SwarmGen template with merge fields matching Ghost post data: {{title}}, {{excerpt}}, {{feature_image}}, {{primary_tag}}, {{published_at}}.
2
Add a Ghost webhook
In Ghost Admin, go to Settings > Integrations > Custom integrations > Add webhook. Select "Post published" as the event and enter your automation endpoint (Make, n8n, or a custom URL).
3
Extract post data and call SwarmGen
In your automation (or serverless function), receive the Ghost webhook payload, pull out the post fields, and POST them to the SwarmGen render API.
4
Update the post or send the image downstream
Use the Ghost Admin API to update the og_image field on the post, or send the image URL to Mailgun/Mailchimp for the newsletter header.

Code example

Ghost webhook → SwarmGen (Node.js handler)javascript

// Serverless function / Express route receiving Ghost webhook
export async function handler(req) {
  const post = req.body.post?.current;
  if (!post) return { statusCode: 400 };

  const renderRes = await fetch(`https://swarmgen.io/api/templates/${process.env.SWARMGEN_TEMPLATE_ID}/render`, {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
      'Authorization': `Bearer ${process.env.SWARMGEN_API_KEY}`,
    },
    body: JSON.stringify({
      data: {
        title: post.title,
        excerpt: post.custom_excerpt || post.excerpt,
        feature_image: post.feature_image,
        primary_tag: post.primary_tag?.name ?? '',
        published_at: new Date(post.published_at).toLocaleDateString('en-GB', {
          day: 'numeric', month: 'long', year: 'numeric',
        }),
      },
      returnUrl: true,
    }),
  });

  const { url, jobId } = await renderRes.json();
  return { statusCode: 200, body: JSON.stringify({ url, jobId }) };
}

Bespoke integrations are not supported by our team. The sample code here is for guidance and you will need technical knowledge or a developer to implement it. We plan to release dedicated plugins for key tools as demand grows.