Send USDC in and it becomes permanent five-cause endowment principal; the principal's earnings buy CEN for the stakers.
The NST vault is a keyless endowment-funding primitive. Anyone can send USDC to it and call deposit(): the resting USDC is split into five equal parts and supplied to the five cause endowments, minting cause-flavor tokens that are held by the vault as corpus. That corpus is permanent — it is recorded only when deposit() mints it, and nothing in the contract can redeem it, sweep it, or send it out.
As a member of the holder-leg family, the vault earns a pro-rata share when the family distributes. A second permissionless button, convert(), spends only those earnings — never the corpus — swapping each earned flavor directly to CEN on that flavor's own CEN pool (paying trading fees into the endowment liquidity) and sending the CEN straight to CEN staking (simple). The split between corpus and spendable earnings is a hard-coded ratchet in the code: convert() may move at most the balance above the recorded corpus, and the internal per-flavor step re-checks that bound.
It is keyless: no owner, no admin, no setter, no pause, no withdraw, no rescue, no sweep. Every destination is welded at deploy — the five endowments, the CEN pools, and the staking address are immutable. The vault is live on-chain and is the welded payout of the NST token (tool 3): the token's harvested yield lands here and becomes five-cause principal. This is a description of how the code is wired, not a promise of any return.