I write my presentations in pandoc and convert them to Beamer. This is a simple presentation, from the [pandoc docs](
https://pandoc.org/MANUAL.html):
% Habits
% John Doe
% March 22, 2005
# In the morning
## Getting up
- Turn off alarm
- Get out of bed
## Breakfast
- Eat eggs
- Drink coffee
# In the evening
## Dinner
- Eat spaghetti
- Drink wine
------------------

## Going to sleep
- Get in bed
- Count sheep
---
One nice bonus of using plain text for my slideshows is that if I need to translate them (I teach in different languages) it's as easy as putting it through google translate or some similar service, and you get your translated presentation at the other end.