Live on Base

Odds. Onchain.

Permissionless infrastructure for prediction markets.
Many venues. One engine.

Launch App→Read the docs

Opinions are free. Prices cost capital.

Run your own prediction market venue

The infrastructure is the hard part. It's already live. Anyone can build on it.

What we built.

Already built onchain, running for everyone.

Orderbook
Onchain limit + market orders
Matching engine
Deterministic, price-time priority
Custody
Collateral held by the protocol
Settlement
Atomic and trustless onchain
Resolution
Two oracles, no privileged resolver
What you build.

Just the frontend — or fork and customize the one we provide.

Markets
Which questions to list, and when
Audience
Who you serve, where they live
Brand
How the venue looks and feels
Experience
The UI, the flows, the product
Distribution
How users find you, and why they stay

Set the rules of your venue.

Access policies and fees, configured per venue, enforced onchain.

Two actions, gated independently
List markets
Choose who can create markets
Place trades
Choose who can trade
Access policies
Open
Anyone with a wallet. Anyone lists, anyone trades.
Whitelist
KYC-style access without intermediaries.
NFT-gated
Only holders of a specific NFT collection.
Token-gated
Only addresses holding a minimum balance of an ERC-20.
Custom
Any access logic the venue implements as a custom smart contract.
Fees
1–200 bps
Venue fee
Your share of every trade in the venue, at a rate you set.
optional
Creator share
A configurable slice of the venue fee paid to whoever lists each market.
50 bps · fixed
Protocol fee
Flat, charged on every trade. Funds protocol infrastructure and development.

How markets get resolved

When a market closes, it needs an answer. OddMaki gets that answer from two sources, depending on the question. Both run onchain. Both are public. Anyone can trigger them, including you.

For questions a human has to answer

UMA V3
"Did the bill pass." "Who won the runoff." "Did the team win Sunday's game."
01
AssertAnyone posts a bond and asserts the outcome.
02
LivenessA configurable dispute window opens. If undisputed, the assertion settles.
03
Dispute (optional)Disputes go to UMA's decentralized voting. The loser's bond is slashed.
04
ResolveThe verified result is reported back. Market settles.

For questions a price answers

Pyth Network
"Will ETH close above $4,000 on July 15." Machine-verifiable. No human needed.
01
SubmitAnyone submits a signed Pyth price update from the resolution moment.
02
VerifyThe protocol verifies the signature and timestamp onchain.
03
CompareReported price is compared to the strike.
04
ResolveInstant. No liveness wait. No dispute possible.

Take your venue live.

01
Create your venue onchain.
From the OddMaki dApp, create your venue, set fees, access rules, and oracle parameters. Fully onchain, permissionless, with no gatekeepers.
02
Deploy your front-end.
Fork the Venue Starter repo and customize it, or build your own with the SDK. No backend required. See it live on Sepolia →
03
List your first markets.
Start listing markets and let trading begin.
Available from the OddMaki dApp or directly in the Venue Starter.
Create a venue→Read the launch guide

Every component, public.

@oddmaki-core
All the smart contracts. Live on Base mainnet.
● live
@oddmaki-venue-starter
White-label, fully featured prediction market dApp.
● live
@oddmaki-sdk
Standalone TypeScript SDK. Published to npm.
● live
@oddmaki-subgraph
Every protocol event indexed and queryable. Hosted on The Graph.
● live
Python and Rust SDKs
Broadening the developer surface.
in progress

What We're Not Doing

No fees to launch.

Deploying and running a venue costs only network gas. No setup fees, no subscriptions, no tiers — nothing sits between you and the protocol.

No protocol-curated markets.

Let one operator pick the markets, and you've recreated the gatekeeper. The protocol has no opinions on what's worth pricing. The world does.

Nothing off-chain that touches user funds.

No matching server. No hot wallet holding user funds. No admin keys to outcomes.

These aren't promises — they're enforced onchain.

OddMaki is open.

You don't need our permission.

You don't need to talk to us.

Start building now.

Start Building→
From the blog

Notes from the protocol.

All posts →
how-to

How to Build Your Own Polymarket

A walkthrough of the decision space for anyone trying to launch a prediction market platform — what "forking Polymarket" really means, what building from scratch requires, and what it looks like to build on top of existing infrastructure.

Read →
essay

Skin in the Game and Prediction Markets

Why I built OddMaki. A reading of Nassim Taleb's *Skin in the Game*, what a trade reveals that a poll doesn't, and the case for many venues instead of one.

Read →
protocol

How OddMaki Works

A long-form walkthrough of the protocol — what's actually onchain, how trades match, how outcomes resolve, what running a venue looks like, and what we deliberately left out.

Read →

If you're launching a prediction market platform: fork the venue starter, brand it, deploy it. The documentation walks through every step. The protocol is open and the front-end is yours.

If you're a developer building infrastructure, bots, agents, or analytics: read the SDK docs, the subgraph schema, the contract source. All of it is public. We'd love to see what you build.

If you're a trader: trade in markets whose prices mean something, because they cost something to produce. Find a venue whose rules you like.

Those who talk should do, and only those who do should talk.
— The OddMaki team

Read why I built this →