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Tāhuna is a decentralized prediction-market protocol in development on Radix mainnet. Anyone can list a market by posting a bond and writing the question; the listed creator then earns a share of every taker fee that market generates, creditable on the spot rather than at resolution. Markets are quoted in xUSDC and priced on an on-chain limit order book. Resolution is not performed by Tāhuna itself but handed to OTER, the optimistic oracle on Radix, for which Tāhuna is the founding integration.

The name is te reo Māori: tāhuna (TAH-hoo-nah) is a sandbank, beach or sandy shore — and the calm shallow water between the sand and the open sea.

Market mechanics

Tāhuna's stated design point is that the whole order book lives on the ledger. Every limit order, fill and cancellation is a Radix transaction and the matching engine runs in the contract, so there is no off-chain matching server, no custodial bridge and no settlement layer above the ledger — a design that leans on Radix's throughput and on the asset-oriented execution described in Scrypto fundamentals. Each market carries a price grid of 99 or 999 levels. An in-house indexing layer reads the on-chain state and republishes it live to the trading interface and over a public API, so integrators read the same feed as the frontend.

Fees run in one direction: the taker pays and the maker is paid back through an on-chain rebate credited per fill, with the fee peaking at 1.80% at 50¢ and tapering toward the ends of the price range. Listing a market is permissionless and free, or revenue-generating in exchange for a 10 xUSDC bond; a curator — human or automated — verifies the wording before a market goes live, after which the listed creator stays attached to it for its lifetime. Creators register once and can list any number of markets under one identity, accruing a share of taker fees across all of them. Beyond the per-fill rebate the project describes a planned off-chain liquidity-rewards programme modelled on Polymarket's, scoring depth and time-on-touch each minute against the same indexed data, on the reasoning that cranking the book on-chain once a minute is not feasible.

The protocol has no token, and the project states there is no presale and no airdrop.

Resolution

Tāhuna describes itself as the markets layer only; confirming an outcome is delegated to OTER, a separate project it depends on. When a market reaches its deadline a proposer submits a candidate outcome and posts a proposer bond, opening a four-hour challenge window. If nobody disputes it, the outcome finalizes, the market settles and the bond is returned — the path the project expects most markets with clear evidence to take, with no vote and no jury.

A challenger who posts a counter-bond escalates the question to OTER, where a weighted jury of staked participants casts timelock-encrypted ballots in a single voting round. No ballot can be decrypted by anyone — including the juror who cast it — until the round closes and drand releases the decryption key, at which point every ballot is decrypted at once and the outcome with the greater stake-weighted total wins. The project contrasts this with UMA's commit–reveal cycle, which it says takes an extra round, and frames its own relationship to OTER as mirroring Polymarket's to UMA. The market creator posts a resolver reward when escalating, so jurors are paid by the market they are resolving.

Note on juror rewards: Tāhuna's resolution page describes jurors earning OTER tokens for participating and resolving correctly, while OTER's own specification states that voters are paid in rUSDC stablecoins rather than a platform token. Both are the projects' own pre-launch documentation and neither has been settled on-ledger; the discrepancy is recorded here rather than resolved.

Status and roadmap

As of July 2026 Tāhuna is pre-launch. Its published timeline targets a testnet in Q3 2026 and mainnet in Q4 2026, and the site offers a waitlist rather than a live application. The Tahuna-Labs GitHub organisation is registered but publishes no public repositories yet, so the contracts are not open to inspection at the time of writing. The project states it is not available to residents of jurisdictions where prediction markets are prohibited.

Tāhuna's dependency on OTER means the two ship on linked timelines: OTER is likewise pre-launch, with its randomness beacon already live in production but the oracle itself not yet on mainnet.

  • OTER — the optimistic oracle that settles Tāhuna's disputed markets
  • Religant — the earlier oracle effort on Radix
  • Oracle Integration — consuming an oracle from a Scrypto blueprint
  • Ociswap — order-book and AMM trading venue on Radix