Goaly

A self-custodial wallet app for football, on Arbitrum. Every player gets a Tether WDK wallet — keys on their device, no seed phrase — to stake and get paid in USDT. Your principal is never at risk: an autonomous agent puts the pool to work in DeFi, and only the yield it earns funds the prizes.

Built for the Tether Developers Cup — WDK (Wallets) track.

Live: app.goaly.fun · api.goaly.fun (docs) · goaly.fun

Built on Tether WDK

Goaly is a WDK app end to end — both the player and the agent hold their own keys:

• Self-custodial player wallet. Every account is a WDK wallet (@tetherto/wdk-wallet-evm) whose keys live on the user's device — no seed phrase to write down. It's derived deterministically from an EIP-712 sign-in signature, so it always restores from the user's connected wallet. Players pay, claim, and send USDT straight from it; WDK handles wallet creation, signing, and accounts.
• Autonomous agent wallet. The yield agent runs on its own WDK wallet, reads Morpho APYs, and reallocates the pooled USDt across DeFi — an agent wallet doing autonomous finance, settling on-chain in USDt.
• Safe by design. App/agent logic is cleanly separated from wallet execution, and on-chain roles are least-privilege: the agent can only rebalance between whitelisted strategies — it can never touch principal or move funds to an EOA. Recovery is deterministic re-derivation, so there's nothing to lose.

Football is the theme; self-custody is the point.

How it works

Players stake USDT (Tether's omnichain USD₮0) on who wins a match. Every stake is pooled into an ERC-4626 vault and put to work earning yield on Morpho; the principal stays fully redeemable 1:1. When a match settles, winners split a prize funded entirely by that yield — the protocol fee is taken from the prize, never the stake. No-loss is enforced on-chain as an invariant (GoalyMarkets.isSolvent()): the vault can only ever earn, so everyone can always withdraw their principal.

"No-loss" means safe from a wrong prediction — not from smart-contract, DeFi or bridge risk.

Architecture

A layered protocol, all deployed and Arbiscan-verified on Arbitrum One:

Contract	Address	Role
GoalyMarkets	0xFAcaD2Cbc3b6320239389aD5c2F597DeE95f1fd3	Prediction layer — predict / claim; routes stakes to the vault, pays yield-funded prizes
GoalyVault	0xFe424b5b85C742C15CCB09d62873bE72577CD7Ef	ERC-4626 (UUPS) vault — pools principal, allocates across strategies, keeps a liquidity buffer
MorphoStrategy	0x6951adCCd2106Bf364D62A1CC328070FC49609eA	Same-asset adapter — supplies USDT0 into a Morpho USDT0 vault
MorphoSwapStrategy	0xD12c112DA7D19266c5cBB9A9bde4Ee9e77D5393D	Cross-asset adapter — swaps USDT0 ↔ USDC into Morpho USDC vaults
GoalySettlement	0xC03BB9526D6F0308d8Ba0831e85f93db3E45e201	Optimistic settlement oracle — bonded propose → dispute window → finalize
ReserveManager	0xCe34457F70733191126726c1D1EeEb52Bcd20051	Bridges surplus only (never principal) cross-chain as USDC via Circle CCTP

Players always stake and withdraw USDT; internally the vault's yield can be earned in USDT0 or USDC. Contract source lives in its own repo, Goaly-Protocol/contracts.

Yield agent

The agent reads Morpho vault APYs and the vault's whitelisted strategies and can rebalance() the pool toward the best risk-adjusted option. It is advisory / governance-gated — same-chain moves only, never to an EOA — so principal always stays on Arbitrum and claims stay no-loss. It signs on its own Tether WDK wallet; see Built on Tether WDK.

Repo layout

This repo is a Bun + Turborepo monorepo for the API and shared packages:

apps/
  api/              Bun + Hono + Drizzle API (→ api.goaly.fun)
packages/
  core/             domain logic — odds model, rebalance policy, cross-chain routing
  plugin-onchain/   viem reads/writes, Morpho data, market settlement
  plugin-odds/      football odds/results feed provider
  plugin-teams/     team / flag / crest resolution
  plugin-wdk/       Tether WDK wallet wrapper (agent + oracle signer)

The dApp (app.goaly.fun), landing (goaly.fun), docs (Mintlify), and contracts each live in their own repository.

Develop

Requires Bun.

bun install
cp .env.example .env      # fill in ORACLE_PK, ARBITRUM_RPC_URL, odds API key, …
bun run dev               # API + packages via Turborepo
bun run test              # workspace tests
bun run typecheck

The API serves at http://localhost:3001 (API reference at /docs).

License

Apache-2.0