Homemade doenjang, normal white crust?

I started my first batch of doenjang three weeks ago, in a stoneware pot a friend brought me from Seoul, and a thin, fluffy white crust has formed on the surface, almost like the bloom on a well-aged Saint-Marcellin cheese. Is this a reassuring sign of fermentation progressing, or should I be worried and remove this film before it turns into something less friendly? Here, with Comté or Beaufort cheese, this kind of crust is often a good sign, but I don't dare apply my usual benchmarks without certainty. The smell is still quite mild for now, almost nutty, with no worrying ammonia notes. If anyone is used to these long maturation processes, I'd love some informed advice before I literally cut into it.