Dragon Fruit Cactus Soil:
I mixed up potting soil, peat moss and grow mulch. I only added a small amount (perhaps 10%) of my native soil. It was very organically rich mix.
The peat moss was added for moisture retention and mild acidification.
The grow mulch was added for lots of organic fertilizer.
The potting soil was to add in for a balanced mix of other organic material and aeration.
I am sure compost would also work great, but I didn’t have any on hand when I transplanted them.
Since then, I continue to pile organic material (grow much/worm castings, compost, etc) around the base of the cactus about 2x a year.