USDG integration

Slate treats Paxos USDG as a first-class unit on Robinhood Chain.

Prices in USDG

SlateQuotedFeed re-quotes any Slate feed (a stock token or a basket NAV) in USDG through Chainlink's USDG/USD feed on Robinhood Chain mainnet, 0x61B7e5650328764B076A108EFF5fa7282a1B9aD2:

price in USDG = price in USD × 10⁸ / USDG-USD

It keeps the base feed's status. It reports STALE if the USDG/USD answer is older than its bound (25 hours) and NO_DATA if it is missing. A USDG depeg is therefore visible in every quoted price instead of silently assumed away.

Buying in USDG

On mainnet, SlateRouter takes USDG as its cash token and prices it with the same Chainlink USDG/USD feed. A fill's effective price is USDG spent × USDG/USD ÷ tokens received. A depeg moves every leg's effective price, and past 3% the router refuses. The unit tests cover a $0.98 USDG, which is accepted, and a $0.96 USDG, which is refused.

On a fork of Robinhood Chain mainnet, through the official SwapRouter02 (0xcaf681a66d020601342297493863e78c959e5cb2) and the live AAPL/USDG pool (0xAae0d815EE56e4092a5E5C2911E676Fea50B2d6D, 0.05% fee), the router bought 0.1 AAPL:

	USDG
Paid	32.79
Fair (Chainlink AAPL × Chainlink USDG/USD)	32.71
Difference	+0.25%, inside the 3% band: accepted

cd contracts && python3 script/rpc_relay.py https://rpc.mainnet.chain.robinhood.com 8548 &
SLATE_FORK=1 SLATE_FORK_URL_rh_mainnet=http://127.0.0.1:8548 \
  forge test --match-test test_aaplUsdgPool_createsWithinTheBand -vv

The same router targets the NVDA/USDG (0xd4EB21209C4D6093f80B5b84f5C45cc093EA14a3) and SPY/USDG (0xa7Bb1AC63BBaB0C44316E6c8C455213441689167) pools.

Testnet: TESTUSD

Robinhood Chain testnet has no Paxos USDG we could verify, and no USDG/USD feed. Slate uses TESTUSD (Slate Test Dollar), 0x239f410D4D2152ba890F378f6B4Aa103B9ea7FEF: 6 decimals, a public faucet() of 10,000 per day, priced at exactly $1 by the router. TESTUSD is a testnet stand-in for Paxos USDG. Not USDG. The name avoids "tUSD", which is one character from TrueUSD.