Where does the vault keep the money — HyperEVM or Hyperliquid Core?

The vault contract lives on HyperEVM, and that's where your deposit lands. To put capital to work, the manager bridges USDC to Hyperliquid Core — where the Flagship trades on the order book, or the Index allocates into native vaults.

The vault's accounting counts both sides (its HyperEVM balance + its equity on Core, read via precompiles), so your share value always reflects the full position. Withdrawals are paid from the liquid HyperEVM side; capital that's actively working becomes withdrawable once the manager brings it back — which is why the app shows a "withdrawable now" figure that can be smaller than your total position.