Contracts overview

Tapehouse is a set of contracts on Robinhood Chain. Two are Stylus programs written in Rust, the band and the margin engine. The rest are Solidity contracts that read them. This page maps the set. Each contract has its own reference page, and Addresses lists every deployed address.

Everything here runs on the Robinhood Chain testnet (chain ID 46630) and is unaudited.

How they relate#

                    Stylus                                  Solidity
              +------------------+
              |  Band            |---- BandFeed (one per asset, seals the band before each reopen)
              |  price + session |---- MorphoBandOracle
              +--------+---------+
                       |
              +--------v---------+      +-----------------+
              |  Margin engine   |<-----|  MarginAccounts |---- SupplyVault (USDG lenders)
              |  portfolio rules |      |  positions      |---- StockLendingVault (one per Stock Token)
              +------------------+      +----+-----+------+---- Basket (index shares as collateral)
                                             |     |
                          +------------------+     +------------+
                          |                                     |
                    +-----v-----+   hold / settle / writeOff   +v-------------+
                    | Liquidator|<-----------------------------| GapBackstop  |
                    +-----+-----+                              +^-------------+
                          |  Dutch auction                      | buyRemainder, cover
                    +-----v--------------+                      |
                    | ReopeningAuction   |----------------------+
                    +--------------------+

    ShortPositions: borrows from each StockLendingVault, sells through Uniswap v3
    GapCover:       reads the band and the margin engine, pays USDG after a closure
    SponsorPaymaster: pays gas through the ERC-4337 EntryPoint

The margin accounts hold every position and call the engine to decide what a position may borrow. The liquidator sells what falls short, in a Dutch auction while the market is open. Over a weekend or holiday closure, the reopening auction sells it in one sealed-bid batch at NYSE's open, and the gap backstop buys what the bids leave and covers what a position still owes after that.

What each contract is for#

Two more Solidity contracts have no page of their own. RedStoneRoundFeed is a Chainlink-compatible feed with rounds, for a chain where an asset has no Chainlink feed, and the gap cover reads it through the band. StockTokenWrapper is a one-to-one ERC-20 over a Stock Token with the views the band and the accounts read.

Repository directories#

The Solidity contracts are compiled with solc 0.8.37 and the Osaka EVM target, built on OpenZeppelin, and tested with Foundry 1.8.3. The SDKs read every address from the registry file and compile none in.

Build and test#

Clone the repository and run:

git clone https://github.com/Tapehouse-Labs/TAPEHOUSE.git tapehouse
cd tapehouse
make build
make test

make build initialises git submodules and installs JavaScript dependencies on first run. It stops with a message if Node, Foundry or cargo-stylus does not match the pinned versions.

Fork tests read the chain through the ROBINHOOD_RPC_URL endpoint that contracts/foundry.toml names.

Verify a deployment#

Each Solidity contract has a make verify-* target that rebuilds its constructor arguments from the chain and verifies it on Sourcify, which supports the three chains the repository targets and the compiler it pins:

make verify-gap-backstop CHAIN=46630
make verify-reopening-auction CHAIN=46630
make verify-stock-lending CHAIN=46630
make verify-short-positions CHAIN=46630
make verify-baskets CHAIN=46630
make verify-sponsor-paymaster CHAIN=46630

The other targets are verify-band-feeds, verify-supply-vault, verify-margin-accounts and verify-liquidator. verify-gap-cover and verify-morpho-oracles accept only CHAIN=4663. A Stylus program verifies by rebuilding it in the reproducible Docker image and comparing it with the code on chain:

make verify-stylus CHAIN=46630 TX=<deployment tx> CONTRACT=<band|margin>

It passes only when cargo-stylus prints Verification successful. Verification covers the procedure.

Next#

• Addresses
• Gap backstop
• Reopening auction
• Quickstart