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How Pregame works

Sportsbooks keep 15–30¢ of every parlay dollar. Pregame puts you on their side of the counter: bettors ask for parlay prices on Polymarket, your engine answers in under half a second, and the margin is yours. Here is the whole machine, in plain terms.

The one-sentence version

You run a tiny automated sportsbook. When someone on Polymarket wants to bet a parlay, your pricing engine offers them a price that includes your profit margin. If they take it, you collect their stake and pay out only if every leg of their parlay hits.

You never pick teams and never bet. You set the rules — how much margin to charge, how much money to risk, which games to touch — and the engine does the quoting, automatically, around the clock.

Two sides of every ticket

Every parlay has a bettor side and a house side. The bettor risks a little to win a lot; the house collects a little and risks a lot — on that one ticket. The house takes that trade all day because parlays rarely hit, and the price of every ticket includes margin.

EXAMPLE — ONE TICKET, BOTH SIDES
Bettor stakes$10 on a 4-leg parlay
If all 4 legs hit, bettor collects$68.54
You (the house) collect now$10.00
You pay out only if all 4 hit$68.54
If ANY single leg misses, the ticket dies and the $10 is yours.

Those are real numbers from a real Pregame fill: a bettor took a 4-leg at 14.59¢ per $1 of payout. One leg missed that night. The house kept the stake.

Where the parlays come from

Polymarket runs a system called Combos RFQ — Request For Quote. When a bettor builds a parlay (say, three baseball moneylines), Polymarket broadcasts the request to every connected market maker: “who will price this?”

Every maker has 400 milliseconds to answer with a signed, binding price. The bettor sees the best one. That request stream runs all day — thousands of parlays per hour on a busy slate — and your engine listens to every single one.

Why speed matters: 400ms is faster than a human can read the request. That is why Pregame exists — no human is ever in the quoting loop. You write policy; the engine does the racing.

The 400-millisecond quote

When a request arrives, your engine runs one pipeline, every time:

  1. Check your rules. Right sport? Games and teams you allow? Leg count inside your band? If anything says no, it skips — skipping is always free.
  2. Price the legs. It reads the live Polymarket market for each leg and multiplies the probabilities into a combined fair value.
  3. Add your margin. Your pricing policy (more below) widens fair value into your quote.
  4. Size it. The quote is capped by your per-ticket limit, your open-exposure limit, and your per-team caps — big requests get sized down, never stretched.
  5. Sign and send. A cryptographically signed quote goes back. If the bettor takes it, the trade settles on-chain automatically.
EXAMPLE — ONE QUOTE, START TO FINISH
Request arrives4 legs, $10 notional
Legs priced from live markets62.5¢ × 58.5¢ × 60.5¢ × 62.5¢
Fair value (multiplied)13.83¢
Your margin+5.5%
Quote sent14.59¢ · in 155ms
Filled. $10.00 collected, $58.54 at risk — a real ticket from the live desk.

Pricing: fair value plus your margin

Fair value is what the parlay is mathematically worth if the legs are independent — just the leg probabilities multiplied. Quote exactly fair and you make nothing; the margin is the business.

Pregame gives you two pricing modes and every dial in between:

  • Follow the market. The engine watches what winning quotes actually charge, per leg count, over the last 24 hours — and prices at a percentage of that you choose. Set 90% and you undercut the going rate; set 110% and you price above it.
  • My prices. Type your own margin for each leg count: say 300 bps on 2-leg tickets, 900 bps on 5-leg tickets. (100 bps = 1%.)

On top of either mode you can set a floor (never quote closer to fair than X), charge extra on specific teams, or pin any single market to a price you believe more than the market does.

EXAMPLE — SAME PARLAY, THREE POLICIES
Fair value of a 3-leg21.6¢
Follow market @ 90% (market clears +5%)22.6¢
My prices: 800 bps flat23.3¢
+200 bps extra on Yankees parlays23.8¢
Wider margin = more per fill, fewer fills. The dial is yours.

Why the house side wins over time

One ticket is a gamble. A book of tickets is a business. Two forces work for you:

  • Margin on every ticket. Every quote is priced above fair value, so across many tickets the average outcome tilts your way — the same reason casinos and sportsbooks are profitable without predicting anything.
  • Margin compounds with legs. A little edge on each leg multiplies: modest per-leg margin becomes 8–15% on a 4-leg and more beyond. That is why parlays are the most profitable product in sports betting.
EXAMPLE — 100 TICKETS, TOY NUMBERS
100 tickets × $10 collected+$1,000
True hit rate at fair value13.8% → ~14 winners expected
Your price implies14.6% → you charged for ~15
~14 payouts × $68.54−$960
Expected profit ≈ your margin × volume. Any single night can lose; the average is priced to win.
Honest version: variance is real. A night where favorites all win pays out many tickets at once. That is what the risk rails below are for — capping how bad any one night can be.

What you collect, and what you put at risk

When a quote fills, two things happen instantly, on-chain:

  • The bettor’s stake lands in your wallet — the premium, collected up front.
  • Your wallet locks collateral for the worst case: the payout minus the stake. That is your at-risk on the ticket.

Settlement is automatic. When the games finish, the ticket resolves on-chain: if any leg missed, your collateral unlocks and the stake was pure margin; if every leg hit, the payout comes from that collateral. Winnings sweep back to your wallet without you touching anything.

EXAMPLE — A FILL, IN WALLET TERMS
Before$510.00 on hand
Fill: collect $10 stake+$10.00
Collateral locked while games play$58.54
A leg misses → collateral unlocks+$58.54 back + settlement
After (real night, fees included)$519.59 — up $9.59
You can never quote money the wallet does not hold. Solvency is enforced in code.

When the bettor wins

Sometimes every leg hits, and you pay — that is the product working, not breaking. Your margin priced that outcome in: winners are (slightly) rarer than the odds you charged for.

What actually protects you is never being too exposed to one outcome:

  • Per-ticket cap — no single ticket can risk more than your number.
  • Per-team caps — tickets that share a team win together; cap any team’s total at-risk so a hot Yankees night cannot stack losses.
  • Open-exposure cap — a ceiling on worst-case payout across every open ticket combined.
EXAMPLE — A LOSING TICKET
Collected on a 3-leg+$25.00
All three legs hit−$180.00 paid out
Net on this ticket−$155.00
Margin on the other 40 tickets that night+$212.00
Books lose tickets and win nights. Caps make sure no ticket can outweigh the night.

Your rules, your book

Every number on the desk is yours to set, to the cent — Pregame recommends, never overrides:

  • What to quote: sports, individual games, individual teams, even a single Over/Under market — each has its own on/off switch.
  • Size: per-ticket cap, total open exposure, fills per day, per-team dollar caps.
  • Price: pricing mode, undercut percentage, margin floor, per-team bumps, per-market pins and skews.
  • Selectivity: leg-count band (2–6 leg tickets only, say) and a fair-price band (skip extreme longshots).
EXAMPLE — A CAUTIOUS FIRST BOOK
Per ticket$25 max at risk
Open exposure$150 across all tickets
Fills5 per day
MenuMLB only · 2–4 legs · no longshots under 5¢
Worst possible day: bounded at $150. Sleep intact.

The safety rails

Underneath your rules sit protections that are not settings — they are physics, enforced in code:

  • Solvency. The engine can never put more at risk than the wallet holds. Ever.
  • Fail closed. Any ambiguity — stale price data, a market moving too fast, a leg it cannot identify — resolves to not quoting. A missed quote costs nothing; a bad quote costs money.
  • Circuit breakers. Error storms, accounting mismatches, or suspicious patterns halt the desk automatically and tell you why, in plain language.
  • No correlated pricing. Two legs from the same game are not independent, so the engine refuses to price them as if they were — a classic way naive makers get picked off.

Watch first, then arm

You never have to start with money on. The Floor — Pregame’s live console — runs in watch mode: you see the real request flow, what the engine would quote under your rules, and what the market is charging, with zero risk.

When the numbers make sense to you, arming the desk is one switch. Stopping is the same switch, and it acts within a second.

Words you’ll see

RFQ (Request For Quote)
A bettor’s parlay, broadcast to market makers for pricing. The start of everything.
Leg
One bet inside a parlay — a moneyline, an Over/Under. All legs must hit for the parlay to pay.
Fair value
The parlay’s mathematical worth: the leg probabilities multiplied together.
Margin / edge
How far above fair value you quote. Measured in basis points: 100 bps = 1%.
Fill
A bettor accepted your quote. You collected the stake; the ticket is live.
At-risk
The collateral a ticket locks: worst-case payout minus the stake you collected.
Premium
The stake you collect up front — yours to keep unless every leg hits.
The book
All your open tickets, viewed as one portfolio of risk and margin.