toml really is best for mostly flat data. when your config grows more complex than that, i recommended you break it into multiple files and use directory struct

toml really is best for mostly flat data. when your config grows more complex than that, i recommended you break it into multiple files and use directory structures or filenames to convey their relationship. or, of course, switch to a configuration format that is more well suited to deeply-nested data. your comparison to yaml or ini is apt; toml's strength over yaml is syntax simplicity and toml is more-or-less a superset of ini (which itself is poorly-defined).