Got funky with trying how far to come with indie coke based on water kefir.
Base is derived from my standard water kefir culture, fed with 3:1 light:dark cane sugar and a tsp of lime juice per litre. All the fancy stuff into 2F: orange honey (as close as you can come to neroli without having this incredible essential oil available), caramel colour, tamarind purée for the extra tang, a tea-like extract of 3 grams cola nuts (those in the glass at the left), and finally another 3 g of soluble instant yerba mate to raise caffeine levels and add some extra tan flavour.
One day of 2F for the fizz, then stored cool for another day. Still foaming was very intense. It tastes great (not quite half as sweet as commercial coke, but hey, that's why we make stuff for ourselves, because the store-bought sugar water is too mellow), and IT LIVES! Cheers!