RobinIndex ($RBDX)

An index token backed by Robinhood Chain Stock Tokens, weighted by each token's own on-chain circulating supply (not real-world market cap — see docs/DESIGN.md §1) — an AUM/adoption-weighted index of Robinhood Chain's tokenized-equity ecosystem. Single-asset mint/redeem is priced by a weight-deviation rebate/penalty (up to ±1%) that incentivizes arbitrageurs to keep the basket at its target weights, computed live on-chain with no admin-fed data.

See docs/DESIGN.md for the full mechanism spec, the researched Robinhood Chain constraints it's built on, and the anti-drain guarantee.

Status & risk disclaimer

Experimental, small-scale project. It has not been reviewed by a law firm or a professional smart-contract audit firm — see docs/DESIGN.md §8 for what's explicitly still open (regulatory review, third-party audit) and why those were consciously deferred rather than done, given the intended pilot-scale/single-operator launch. If this ever moves beyond that — wider usage, active marketing, meaningfully more capital — those two items stop being deferrable and need to happen first. Nothing here is financial or legal advice, and interacting with any deployment of these contracts (testnet or mainnet) is at your own risk.

Structure

src/
  RBDXToken.sol       ERC-20 share token (mint/burn restricted to the vault)
  RBDXVault.sol        Core: holds the basket, mint()/redeem(), fee + rebate logic
  AssetRegistry.sol    Governance-controlled asset list; target weight computed
                        live from each token's on-chain totalSupply()
  libraries/OracleLib.sol   Chainlink read + staleness check
  interfaces/          AggregatorV3Interface, IStockToken
test/
  RBDXVault.t.sol       Unit tests, incl. the anti-drain scenario
  mocks/                MockStockToken, MockAggregator
docs/
  DESIGN.md             Full spec
frontend/
  (Vite + React + wagmi/viem dapp — holdings table + mint/redeem UI,
   deployed to GitHub Pages on every push to main, see frontend/README.md)
script/
  DeployRBDX.s.sol         Testnet deploy (mock Chainlink feeds — real ones
                            don't exist on Robinhood Chain testnet)
  DeployRBDXMainnet.s.sol  Mainnet deploy — lists real Stock Tokens against
                            their real Chainlink Data Feeds, no mocks
  config/assets.mainnet.json  The 27-asset mainnet launch list (individual
                            Stock Tokens only — see that file's header for
                            the full selection rationale)

Setup

Requires Foundry:

curl -L https://foundry.paradigm.xyz | bash
foundryup

Dependencies are git submodules (already vendored in this repo):

git submodule update --init --recursive

Build & test

forge build
forge test -vv

Status: 20/20 tests passing.

Live on Robinhood Chain mainnet (since 2026-09-06)

App	robinindex.com
Chain	Robinhood Chain, id 4663, RPC https://rpc.mainnet.chain.robinhood.com
RBDXToken	0x1914C83bc4E8bB36EB8eaA36f866969Fd2252030 (verified)
RBDXVault	0xc3ce9C84E9E012A32dFf7B7B0E2d44A30A96477e (verified)
AssetRegistry	0x6b61Aa9576Eb6Cbb19ac6aB350519Ac37f9CCE79 (verified)
Admin	2-of-3 Safe 0x904B8B54b3734C2Bb0E26b06ab41E1d22a459eF8
DEX	RBDX/USDG 0.25% on Uniswap v4
Assets	27 individual-company Stock Tokens, see script/config/assets.mainnet.json
Launch thread	x.com/DefiNPCMan

Try it (non-US persons only)

1. Add Robinhood Chain to your wallet (chain id 4663) and hold a listed Stock Token (buy one on Uniswap on Robinhood Chain, or move one from Robinhood Wallet).
2. Open robinindex.com, connect, pick the asset, enter an amount. The panel shows the exact discount/penalty and RBDX out before you sign; depositing an underweight asset (anything the vault holds little of) earns a rebate.
3. Redeem the same way in reverse, into any listed asset. RBDX is a plain ERC-20 and also trades on Uniswap.

Pilot scale: read the status & risk disclaimer and docs/DESIGN.md §8 (open items: third-party audit, legal review, after-hours oracle trade-off) before putting in anything you can't afford to lose.