This is interesting how people promoting Fedimint actually mention all properties of the Standard Sats open source software. Let's look at direct quotes:
Instead of being your own bank, you can be your own community bank. — Obi Nwosu
Then, the author of Trezor blog continues:
Fedimint recognizes that some people within any community are more bitcoin-savvy, and therefore more suited to safeguard the group’s bitcoin than others. This core collective of people will do the heavy lifting of hosting the wallet, processing transactions, securing keys, and ensuring privacy is protected. Hence, their role as “guardians.” The remainder of the community are known as the users.
Standard Sats works exactly like that: the bitcoin-savvy uncle Jim deploys Core node, Eclair LN client, a couple of plugins maintained by Standard Sats: fiat channels plugin and hosted channels plugin, and a hedging service which uncle Jim links to his exchange account. Why he needs an exchange account? That's simple, for hedging bitcoins he receives into Fiat Channels of his brothers, sisters, and nephews.
All hype around Fedimint ignores this simple problem: custodians will need to hedge their market risk if they mint "stable" e-cash. They inevitably land some of their funds in centralized exchanges as long as decentralized solutions aren't ready.
On the other hand, if uncle Jim is alone in the village, with whom he will manage to form the Federation? Interesting question. He eventually might be trusting some dudes he knows overseas and it will be unbelievably good if one of the Fedimint's servers will be controlled by a developer like Fiatjaf. But there is no guarantee.
Standard Sats is not a bunch of software that may run as a back end. It is also a user-facing fork of Simple Bitcoin Wallet. Everything is ready for testing. In addition to Fiat Channels, which work with LN natively, users can send and receive on-chain transactions, and this is important that they can open real Lightning Network private channels with sats!
Everybody is welcome to try custodial channels with synthetic USD, EUR, and "dead" fiat currencies as well, for example, Deutsche Mark or Latvian Lat pegged to EUR.