Overview

How XosBridge connects token markets

Every admitted token has its own Uniswap v4 pool against ETH. A hook on that pool takes a 1% community fee on every buy and sell, in ETH, and records which market it came from. Once a day, the fees each market sourced are allocated to holders of the other admitted markets, weighted by how long and how much they held. The allocation is published as a reproducible artifact plus a Merkle root; holders claim on chain. "Bridge" means the connection between communities. Nothing is transferred between chains.

Fee arithmetic

Three separate costs

• Only exact-input swaps are supported; exact-output swaps revert in the hook.
• Buy (ETH → token): fee = floor(amountIn × 100 / 10000) taken in beforeSwap from the specified currency. The pool swaps amountIn − fee. You pay exactly amountIn.
• Sell (token → ETH): fee = floor(ethOut × 100 / 10000) taken in afterSwap from the unspecified currency. You receive ethOut − fee.
• Rounding is always down, towards the trader. Buys under 100 wei pay no fee.
• The fee is moved to the vault inside the same callback with PoolManager.take; the hook never holds funds and never swaps the fee into another asset.
• No fee is collected while fewer than two markets are admitted, while collection is paused, or on a market that is not admitted. The market page shows this as "fee off".

Worked examples are replayed by contracts/test/unit/Hook.t.sol and documented in docs/FEES.md.

Reward specification (rules v1)

Daily epochs, fixed eligible set, time-weighted balances

• Epoch n = [genesis + n·L, genesis + (n+1)·L) in block timestamps; L is 86400 s on this network.
• The eligible set is fixed at the boundary: markets admitted before the epoch starts and not removed before it. Admissions during an epoch count from the next one.
• Fees from source A exclude A's holders and are split equally across the other eligible communities with non-zero weight; inside a community, by time-weighted balance derived from the complete transfer history (opening balance + every transfer, integer seconds).
• A wallet holding several eligible tokens earns through each. Holding only A never earns from A.
• Declared nonparticipating addresses (PoolManager, locker, launchpad, vault, distributor, hook, router, burn addresses, and any address the registry excludes) carry no weight.
• No recipient with weight → the amount carries forward, still tagged with its source. Rounding dust carries forward the same way. Nothing is ever diverted to the team.
• Epochs are computed strictly in order from finalized blocks only. A reorg deeper than the finality depth after publication is handled by invalidation before activation; after activation a root is immutable.

Full text with every edge case: docs/REWARDS.md. Executable form: src/protocol/epoch.ts, tests in src/protocol/__tests__.

Launch requirements

What a launch is and what it enforces

• Standardized ERC-20: fixed supply minted once, no mint, no tax, no blacklist, no pause, no owner (XosToken.sol).
• One transaction: token + pool initialization (LP fee 0.30%, tick spacing 60, ETH as currency0) + full-range liquidity into the LiquidityLocker + registry entry. It cannot half-complete.
• Creator allocation ≤ 50%, sent to the creator and not locked. Liquidity lock ≥ 30 days or permanent, enforced by the locker; LP fees are collectable by the creator at any time.
• Minimum initial liquidity: 0.05 ETH.
• Admission is a curated decision by the registry owner and requires the lock to still be active. It reduces abuse (mass token creation against equal per-community allocation) but does not eliminate manipulation.

Roles and trust

Who can do what

On a public deployment the registry, vault, distributor and launchpad owners should be one multisig and the publisher a separate operational key. A published root proves the publisher committed to an allocation, not that it is fair; fairness is checked by reproduction during the review window.

Network status

Robinhood Chain (chain 4663)

• Uniswap v4 PoolManager: 0x8366a39CC670B4001A1121B8F6A443A643e40951 (official, verified against developers.uniswap.org and Sourcify)
• Quoter: 0x8Dc178eFB8111BB0973Dd9d722ebeFF267c98F94
• XosBridge contracts: deployed (see below)
• Contracts build: solc 0.8.26+commit.8a97fa7a, EVM cancun, via-IR true, optimizer runs 44444444.

Contracts

Address manifest

Verify an epoch

Reproduce the allocation yourself

# with your own RPC + database (see README)
pnpm build:contracts
pnpm worker --once            # index to the current head
pnpm epoch:verify <epochId>   # recompute from indexed inputs, compare root + artifact hash on chain
# exit code 0 = reproduces byte for byte; 2 = mismatch (do not let it activate)

Artifacts are served at /api/epochs/<id>/artifact and committed on chain as keccak256(canonical JSON). See the rewards page for the review window of each epoch.

Bridge

ETH in and out of Robinhood Chain via Relay

• Relay (relay.link) is an intents bridge listed on Robinhood Chain's official Bridging page next to the canonical Arbitrum bridge, Across, LayerZero, CCIP and LiFi.
• The app proxies Relay's public API (/api/bridge/quote, /api/bridge/status) with input validation and rate limits; an optional RELAY_API_KEY raises limits and is never sent to the browser.
• You sign the deposit transaction Relay returns for your quote, on the source chain. The form refuses a transaction whose value or chain differs from what you entered, re-quotes right before signing, shows the deposit target and whether it is a contract, and tracks the fill by request id.
• Trust: Relay's solvers custody funds between deposit and fill. XosBridge takes no fee, holds no funds and cannot reverse a transfer. Failed fills are refunded by Relay on the source chain per their status endpoint.
• Verified 2026-09-23: chain 4663 is present in api.relay.link/chains with deposits enabled; a live Ethereum→Robinhood ETH quote returned an executable step whose target is a contract on Ethereum.

Token

$XOSBRG

Contract address on Robinhood Chain: 0x9cda040Ba6431370c3498f686178365Bd863d077. The address is published only through pnpm token:ca 0x…, which checks bytecode, ERC-20 views, supply and symbol on chain 4663 before writing it to the site. Until then every surface says "CA: Soon". Verify any address you see elsewhere against this page and @XosBridge. No utility, yield or return is promised for the token.