I need create bitcoin wallet for many users but I have no idea how to do it. Before that I thought to do it with bitcoin-core. But it turned out that accounts are not what I need. In the new version (v.0.15.0) of the bitcoin-core there are multi-wallets, but to add a new wallet it is necessary to restart the daemon. Who can tell me?
To manage many users balances, you should generate a new deposit address for each person, and keep track of their balances via your own database or similar, rather than relying on the deprecated account system in bitcoin core.