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A real-time event exchange that settles with parity.

Buy and sell shares in real-world outcomes. Orders match in milliseconds and money moves in the same breath — one ledger, globally consistent, no clearinghouse in the middle.

Continue with GoogleSee how it works

Trending markets

Every trade settles in a single globally-consistent transaction — no clearinghouse.

Fed cuts in March · YESlive
PriceSizeDepth
  • 0.71184030%
  • 0.70312051%
  • 0.69227537%
  • 0.68541088%
  • 0.67129021%
Last$0.665
  • 0.66483079%
  • 0.656120100%
  • 0.64294048%
  • 0.63387063%
  • 0.62156025%

Every exchange needs a clearinghouse, a ledger, and an infra team.

That's three hard problems before you match a single order. Most of them exist only because the database underneath can't keep one consistent truth across the world.

  • 01

    A clearinghouse

    Someone has to stand between buyer and seller, guarantee the trade, and hold the risk until it settles.

  • 02

    A ledger

    Every balance, every position, every cent — recorded once, agreed on by everyone, never double-counted.

  • 03

    An infra team

    Replication, failover, reconciliation, on-call. The machinery that keeps the truth consistent across regions.

The matching engine is easy. The ledger is the hard part.

Parity puts the ledger in Amazon Aurora DSQL — a distributed SQL database with strong consistency and optimistic concurrency. Money moves between distinct account rows inside a single transaction, and conflicting trades simply retry.

  1. 01

    Incoming orders

    Bids and asks arrive from every region and hit the gateway.

  2. 02

    Per-market matching

    Each market runs its own matching loop, pairing the best bid with the best ask.

  3. 03

    DSQL ledger write

    The fill and its money movement commit as one Aurora DSQL transaction.

  4. 04

    Retry on conflict

    If two matches touch the same row, the loser retries — no locks, no lost writes.

AI market agentVercel CronROADMAPcreates markets+ seeds liquidity(roadmap)ClientVercel / Next.js/api match handlerper-marketAurora DSQLledgerper-market matchingcontention scoped per marketDISTINCT account rowsOCC-friendly writesretry on 40001backoff + jitterdebit / credit · distinct rowsTokyoap-northeast-1Seoulap-northeast-2ROADMAPactive-activestrong consistency(roadmap)one short transaction · commit or retry · no clearinghouse

  • SNAPSHOT ISOLATION

    Optimistic concurrency

    Transactions read a consistent snapshot and commit only if no one else touched their rows. Conflicts are caught at commit, then retried — so matching stays lock-free under load.

  • DISTINCT-ROW WRITES

    Money moves between accounts

    A settlement debits one account row and credits another. Because the writes target distinct rows, independent trades commit in parallel without contending.

  • STRONG CONSISTENCY

    One ledger, everywhere

    Aurora DSQL gives every region the same committed state. There is no eventual window where two traders disagree about a balance.

What the consistency model buys you.

  • CONSISTENCY

    Strong Consistency

    Every reader sees the same ledger at the same instant. No stale reads, no reconciliation jobs.

  • SETTLEMENT

    Instant Settlement

    A fill and its money movement commit in one transaction. The position is final the moment it prints.

  • TOPOLOGY

    Multi-Region Active-Active

    Write in Tokyo, write in Seoul, read the truth everywhere. No primary, no failover drill.

  • OPERATIONS

    Zero-Ops Serverless

    No clusters to size, patch, or page on. Capacity scales with the order flow.

  • MATCHING

    OCC-Aware Matching

    Optimistic concurrency lets matches race, then retries the loser. Throughput without locks.

  • INTEGRITY

    No Double-Spend

    Balances move between distinct account rows. The same dollar can never settle twice.

200 trades collide. The ledger still nets to zero.

We fire two hundred conflicting trades at the same markets at once. Every debit finds its credit. When the dust settles, the books balance exactly — no drift, no reconciliation pass.

Unsettled imbalance

200

Settled

0/200

Strong consistency under contention — not eventual.

Live in one region. Multi-region by design.

Parity runs today on a single Aurora DSQL region in Tokyo — strong consistency under contention, no clearinghouse. DSQL's active-active multi-region (same-continent, e.g. Tokyo + Seoul) is a configuration change away, not a re-architecture: the same distinct-row, OCC-safe ledger extends across regions unchanged.

TokyoAP-NORTHEAST-1SeoulAP-NORTHEAST-2

  • Tokyo

    AP-NORTHEAST-1

    live · accepting writes

    35.6762° N

  • Seoul

    AP-NORTHEAST-2

    multi-region ready

    37.5665° N

  • Strong consistency

    Today: single-region strong consistency under contention — proven by 200+ concurrent trades netting to exactly zero. The same OCC model extends to active-active multi-region with no code changes.

Three steps from question to settled.

  1. 1

    Pick a market

    Fed cuts in March62¢
    BTC > $150k38¢
    GPT-6 ships27¢

    Browse open questions and choose one. Each market resolves YES or NO against a real-world outcome.

  2. 2

    Place an order

    SideBUY YES
    Price$0.62
    Size500
    Place order

    Set a price and size for YES or NO. Your order rests on the book until it matches.

  3. 3

    Watch it settle

    Matched500 @ $0.62
    Debit cash-$310.00
    Credit position+500 YES
    settled

    When you match, the fill and the money movement commit together. The position is final immediately.

One fill, fully labeled.

Fed cuts in March · order book
0.642,940
0.633,870
10.625,410
3MATCH500 @ $0.62
20.616,120
0.602,275
0.591,560
4Ledger transaction
cash
-$310.00
position
+500 YES
5Settled position

500 YES

avg $0.62 · final

  • 1

    BEST ASK

    Lowest price a seller will take. Your buy fills here first.

  • 2

    BEST BID

    Highest price a buyer offers. Your sell fills here first.

  • 3

    THE MATCH

    Buy meets sell at $0.62. The fill prints and triggers settlement.

  • 4

    LEDGER MOVE

    Cash debits one row, the position credits another — one transaction.

  • 5

    SETTLED POSITION

    500 YES shares, final and queryable the instant they commit.

A sample of what's open.

Every card is a market with a live YES price and rolling volume. Tap in to see the book.

Aurora DSQL + Vercel. Shippable Monday.

No clearinghouse to license, no replication to babysit. A real exchange on managed infrastructure — consistent, global, and ready to trade.

  • Amazon Aurora DSQL

    Strongly-consistent, multi-region ledger

  • Vercel

    Edge delivery, serverless compute, zero-ops deploys