ACCA on currency [1]: "An entity’s functional currency is the currency of the primary economic environment in which the entity operates, normally the one in which it primarily generates and expends cash." So it seems it could be allowable for a US-firm to follow GAAP while accounting in crypto. Wasn't expecting that.

Perhaps I'm naive but since primary currency is no more than a convention in your bookkeeping software: find a firm willing to put BTC (or whichever) where usually there is USD?

One of the things to be mindful of is that tax accounting is not GAAP financial accounting. Say you close your book year in a period with high volatility in your cryptos price. This might materially impact your fiat numbers (if you have enough fiat costs). Your tax auditor might want to look twice at the reported fiat numbers.

[1] https://www.accaglobal.com/us/en/technical-activities/techni...