Generating social media posts to promote blog posts with {shiny} and {ellmer}

Writing blog posts is fun, but the next step, getting people to actually read them, can be trickier. I wanted to promote a recent blog post I co-authored for R-Ladies, but coming up with multiple social media posts felt like a bit of a chore.Instead of doing it it manually, I decided to automate the process by building a Shiny app that generates social media content using large language models (LLMs). It was a fun little project, and could even be useful for others too!

The Solution: A Shiny App Powered by AI

The app does the following:

• Takes a GitHub Markdown link as input.
• Lets users specify hashtags, the number of posts to generate, and whether or not to use emojis.
• Allows selection of tone (e.g., serious, playful, informative).
• Calls Google’s Gemini API via the ellmer package to generate social media posts promotinhg the blog post.

Why ellmer and the Gemini API?

The ellmer package was released last year, and is a delightfully straightforward way to directly call LLMs from R. Google’s Gemini API, in particular, offers a generous free tier - up to 15 requests per minute, which was more than enough for my needs.

How It Works

The app is simple:

1. Enter the GitHub Markdown file link (or other text source).
2. Set your preferences—hashtags, emojis, tone, and how many posts to generate.
3. Click generate, and it spits out a bunch of posts.
4. Copy and paste into your social media scheduler.

Under the hood, it builds a prompt using the user’s inputs and calls the Gemini API. The response is formatted into platform-appropriate posts, making it much easier to schedule across different social networks.

Preview of the app

Deployment Considerations

Right now, the app runs locally, and users need to enter their own Gemini API key as an evironment variable. This prevents abuse of a shared key, but it also makes the app a bit more DIY. I’m considering deploying it on Posit Connect Cloud or a similar service in the future. The trick will be allowing users to bring their own API keys while keeping things secure.

Another thought: supporting multiple AI models so users can plug in API keys for different services like OpenAI’s ChatGPT or Anthropic’s Claude.

Future Ideas

Some things I’d love to add:

• More refined prompts tailored to different platforms (e.g., longer for LinkedIn, punchier for Bluesky).
• Suggested images to go with posts.

Try It Yourself!

Want to give it a go? You can find the repo here: https://github.com/thisisnic/socialmediagen

Wrapping Up

This was a fun little side project that turned out to be actually useful - I’m going to be using it to promote this blog post!

I’d love to hear if you have any ideas for improvements—hit me up if you try it out!