Short answer

For this app, markdown is the better default.

Start with markdown now. Move to a CMS only when the workflow genuinely needs it.

Choose markdown when

• developers are publishing the posts
• content volume is still modest
• you want low cost and low complexity
• you want content reviewed in pull requests

Choose a direct blog system when

• non-technical editors need a dashboard
• you need drafts, approvals, scheduling, or author permissions
• content updates happen every day
• marketing wants to manage everything without code deploys

Recommendation for Extraa

The repo-based structure is the cleanest first step because it matches how the rest of the app is already built. It is fast, easy to maintain, and good for SEO pages, guides, and launch articles.