One ticker. The whole basket.

An ETF is an ERC-20 unit token whose supply is always backed by a vault of 2–10 component tokens. Units are minted only when the exact pro-rata slice of every component is deposited, and burned only when that slice is withdrawn. Nothing is minted against a price feed; the vault is the source of truth.

• Permissionless. Anyone can issue an ETF over any tokens that have a funded WBNB pool on PancakeSwap V2 or V3. No listing process by default.
• In kind. Redemption pays out the underlying coins, never a synthetic claim. Selling for BNB is a convenience layer on top of redemption.
• Non-custodial. No admin key can move vault assets, pause redemptions or change an ETF's basket after issuance.
• Manager economics. The issuer of an ETF — its manager — earns 70% of a 1% desk fee (paid instantly in BNB) and 70% of a streaming expense ratio (paid in units) for as long as the ETF holds assets.

Four contracts, one of which is deployed per ETF:

user ──BNB──▶ EtfDesk ──issueFor / isEtf──▶ EtfIssuer ──new──▶ MemeEtf (vault + ERC-20)
                 │  ▲                                                 ▲
                 │  └── venue / quote ── PancakeQuoter ───────────────┘ (aum / unitPrice views)
                 └── swaps ──▶ PancakeSwap V2 Router / V3 SwapRouter ──▶ tokens ──subscribe──▶ MemeEtf

The quoter is the only upgradeable pointer (EtfIssuer.setQuoter). Swapping it changes how AUM is displayed and how the desk splits BNB; it cannot change what a unit is redeemable for.

1 · Issue and seed

EtfDesk.issueAndSeed(name, symbol, components, allocations, expenseRatioBps, minUnits) with msg.value as the opening subscription. In one transaction the desk asks the issuer to deploy the ETF with manager = msg.sender, takes the desk fee, splits the remaining BNB by target allocation, buys each component on its deepest venue and calls MemeEtf.subscribe. Because issuance and seed settle atomically, an ETF is never listed empty and its opening basket cannot be front-run.

The first subscription prices units at ISSUE_PRICE = 0.01 BNB of value per unit, valued on the tokens that actually landed in the vault (so fee-on-transfer tokens cannot over-mint).

2 · Buy

EtfDesk.enter(etf, minUnits). After the desk fee, BNB is split by current value weights (reserves × quote) so every leg purchases the same unit fraction. The desk mints the largest units that every purchased leg can cover, pulls exactly quoteSubscribe(units) into the vault and refunds any rounding surplus in kind to the buyer. Direct in-kind subscription via MemeEtf.subscribe(units, maxIn) is also supported.

3 · Sell

EtfDesk.exit(etf, units, minBnbOut). Units are pulled, redeemed in kind to the desk, each leg is swapped to BNB on its deepest venue, the desk fee is taken from gross proceeds and the remainder is paid to the seller. Requires a prior approve of units to the desk.

4 · Redeem

MemeEtf.redeemInKind(units, minOut). Burns units and transfers reserves[i] × units / totalSupply of each component to the caller. No fee, no permission, no lock-up. This path never touches an AMM or a price and is therefore the protocol's safety exit.

aum = Σ reserves[i] × quote(token[i]) / 1e18 and unitPrice = aum × 1e18 / totalSupply. Quotes are decimals-agnostic: the quoter returns BNB wei per 1e18 raw token units, so the same formula works for 8-, 9- and 18-decimal tokens.

Venue selection. For each token the quoter inspects the PancakeSwap V2 WBNB pair and the four V3 fee tiers (0.01%, 0.05%, 0.25%, 1%) and picks the pool holding the most WBNB. The desk trades on that same pool. V2 quote is reserveWBNB / reserveToken; V3 quote is derived from slot0.sqrtPriceX96.

Quotes are informational. They drive the board and account figures and the BNB split inside the desk. They never determine how many units a deposit mints after the seed, nor what a unit redeems for.

Expense accrual is linear: units = totalSupply × expenseRatioBps × Δt / (10 000 × 365 days). Minting these units dilutes holders by exactly the expense ratio — standard ETF mechanics — while vault reserves are untouched. quoteSubscribe and quoteRedeem already include accrued expense units, so quotes match execution within the same block.

If a manager address cannot receive BNB (e.g. a contract without a payable fallback), its desk-fee cut falls through to the treasury rather than blocking the trade.

Enforced by EtfIssuer at issuance; an ETF that violates any rule cannot be deployed.

Composition, allocations and the expense ratio are immutable after issuance. Allocations are targets for the opening subscription only; they drift with price afterwards. This is a passive ETF, not a rebalancer.

• No oracle on the safety path. Subscription (after seed) and redemption are pure functions of vault balances and unit supply. Manipulating a PancakeSwap pool can distort displayed AUM or make a desk trade unattractive, but cannot extract more coins than a unit is backed by.
• Slippage is user-controlled. minUnits / minBnbOut guard the whole basket trade; maxIn / minOut guard direct in-kind flows per token.
• Reentrancy. ETF and desk entry points are nonReentrant; token transfers use SafeERC20 with balance-delta accounting for fee-on-transfer tokens.
• Atomic seed. Issuance and opening subscription are one transaction, eliminating empty-ETF and opening-basket front-running windows.
• Desk holds nothing. Every desk call ends with zero BNB and zero token balance; surplus is refunded to the caller within the same transaction.
• Admin surface. The treasury owner can update the quoter, desk, treasury address, desk fee (≤ 3%), issuance limits and listing requirement. It cannot touch any ETF's assets, supply or basket.
• Residual risks. Component token risk (malicious or upgradeable tokens, transfer taxes, blacklists) is inherited by the basket. Thin pools mean higher price impact on desk trades; redemption in kind is always available as the exit.

EtfIssuer

issue(string name, string symbol, address[] components, uint16[] allocations, uint16 expenseRatioBps) → address
etfs(uint256) → address · etfCount() → uint256 · isEtf(address) → bool
quoter() · desk() · treasury() · treasuryShareBps()
minComponents() · maxComponents() · maxAllocationBps() · maxExpenseRatioBps() · listingRequired() · listed(address)
event EtfIssued(address etf, address manager, string name, string symbol, address[] components, uint16[] allocations, uint16 expenseRatioBps)

MemeEtf (ERC-20)

components() → address[] · allocations() → uint16[] · reserves() → uint256[]
aum() · unitPrice() · accruedExpenseUnits() · lastExpenseAt()
manager() · treasury() · expenseRatioBps() · treasuryShareBps()
quoteSubscribe(uint256 units) → uint256[] · quoteRedeem(uint256 units) → uint256[]
subscribe(uint256 units, uint256[] maxIn) → uint256[] · redeemInKind(uint256 units, uint256[] minOut) → uint256[]
collectExpense()

EtfDesk

enter(address etf, uint256 minUnits) payable → uint256 units
exit(address etf, uint256 units, uint256 minBnbOut) → uint256 bnbOut
issueAndSeed(string name, string symbol, address[] components, uint16[] allocations, uint16 expenseRatioBps, uint256 minUnits) payable → (address etf, uint256 units)
deskFeeBps() → uint16

PancakeQuoter

quote(address token) → uint256  (BNB wei per 1e18 raw units)
venue(address token) → (address pool, uint8 kind, uint24 fee)  kind: 0 none · 1 V2 · 2 V3