Turn a blog post into a LinkedIn carousel

LinkedIn carousels (swipeable PDF “document” posts) are some of the highest-engagement content on the platform — but tedious to make by hand. This workflow summarizes a new blog post into 5 slides with an LLM, generates a background per slide, and has Posta composite the text and build the PDF. See the full write-up in From article to LinkedIn carousel.

How it works

1. RSS Read → Latest post (Code) — read your blog feed and pick the most recent article.
2. Basic LLM Chain with the DeepSeek Chat Model — summarize the article into copy for 5 slides (title + body each) plus caption hashtags. Edit the prompt for a different slide count.
3. Parse (Code) → Split Out — parse the model’s JSON and split it into one item per slide.
4. Generate media using AI model (fal.ai) — generate an abstract background per slide (the template uses Recraft V3).
5. Re-assemble (Code) — recombine into a slides array of { media_id, title, body }.
6. theme_color (Set) — set one color used across every slide so the deck looks cohesive.
7. Generate Text Carousel PDF (Posta) — composites the text over each background and builds the PDF. Optionally set a Logo Media ID to brand every slide.
8. Create a post (Posta) — attach the generated PDF to a LinkedIn document post.

Requirements

The text-carousel endpoint is a Professional-plan Posta feature. You’ll also need a DeepSeek key (any LLM works — swap the chat model) and a fal.ai key for backgrounds.

Tips

• Background style is set entirely by the fal prompt — deep, single-hue gradients read best behind the white slide text.
• Upload a logo once and pass its media id as logo_media_id to brand every slide.
• Swap the trigger for a Schedule Trigger to auto-publish a carousel for each new post.