TOML as default, YAML when you know you need it

Takeaways from: stackoverflow.com/questions/65283208/toml-vs-yaml-vs-strictyaml

In summary, YAML isn't actually sloppy #tech, but it's full of features that most people don't use. For example, you can write a value 1d6 and have that parsed as an object {number: 1, sides: 6}!

When you do have use for stuff like that, you'll know.

However… most uses of YAML/TOML/JSON files just have a program read in the data in a simplistic way to transform into a table or map object, end of story. You're not looking for any sophistications.

In that case, TOML serves better because fewer possibilities in syntax means it's able to give more specific error messages when the file is misformatted.