Edit the source
Text, images, tables, code blocks, and speaker notes stay connected to the Markdown they came from.
Slides that stay Markdown.
Build and edit presentations from ordinary Markdown files. Hadar keeps the source in place while you preview, present, and export the deck.
report.md
---
theme: dark
---
# Quarterly report
## 2026 Q3
---
# Next steps
Keep the source editable.Slide preview
A presentation workflow, without a second source of truth.
Hadar is a Ruby library for apps that need editable decks and reliable output.
Present with context
Use live preview, keyboard navigation, and a presenter view that shows the next slide and your notes.
Export the deck
Produce searchable PDF pages, a PNG sequence, or an animated PNG from supported layouts.
Start with a Markdown file.
Requires CRuby 3.2 or newer. Hadar is a library; it does not install a command-line executable.
Terminal
Explore the Ruby API
gem install hadar