Ex-Sushi CTO Joseph DeLong to Launch Order Book DEX on Robinhood Chain

Joseph DeLong, the former SushiSwap CTO who now runs stablecoin card startup Colossus, said he will launch a decentralized exchange called Deepstate on Robinhood Chain next week.

"I have a decentralized exchange side project that outgrew nights and weekends. I'm gonna launch it next week on @robinhood chain," DeLong wrote on X on July 24, linking to a whitepaper published on GitHub.

A Fully Onchain Order Book

The whitepaper, dated June 29 and authored by DeLong, specifies a limit order book that lives entirely in smart contract storage. Each resting order is packed into a single 32-byte word — price tick, quantity, a rounding-correction code, and a time-priority nonce — and stored in a binary radix tree keyed by price and arrival order. The design offers 4.3 billion logarithmically spaced price ticks and caps the work each trade performs at the tree's fixed 64-bit depth, an attempt to keep gas costs bounded no matter how many orders rest on the book.

Fully onchain central limit order books remain rare on EVM chains because every storage read and write costs gas. Most order book exchanges match trades offchain and settle onchain, while automated market makers avoid matching altogether. DeLong's paper credits the core construction to Warp, a matching engine design that Plasma co-author Joseph Poon and Christopher Jeffrey presented at EthCC in 2023.

DeLong was SushiSwap's CTO until his resignation in December 2021, and later argued DAOs need hierarchy in an ETHDenver postmortem on his time at Sushi. He went on to found NFT lending protocol Astaria and to a senior director role at Kraken. Today he is CEO of Colossus, a startup building a stablecoin credit card network designed to bypass Visa and Mastercard.

Robinhood Chain's DEX Race

Deepstate would join a crowded field. Robinhood launched its Arbitrum-based chain's public mainnet on July 1 with Uniswap, 1inch, Arcus, and perpetuals partner Lighter live from day one, and the network has grown quickly: it overtook Base on daily active users on July 21, registering 323,969 addresses against Base's 274,520 three weeks after launch. Lighter has since made Robinhood's stock tokens eligible collateral for its perps markets.

DeLong gave no launch date beyond "next week" and did not name trading pairs, fees, or a token.