exactodds

ExactOdds

Run games? Read the operator one-pager · full paper · commercial license: corey@slidphilabs.com

What ExactOdds is

ExactOdds makes dice that can’t lie. It provides the core building blocks for games of chance — dice rolls, coin flips — with the math out in the open and every result verifiable. If a result can’t be proven fair, it is refused.

Here is why that matters. An online game runs the same code on many platforms — a phone, a browser, a server — and players have to trust that the house didn’t tilt the odds on any one of them. ExactOdds removes the need for trust: the reference games are run through five programming languages — Python, JavaScript, TypeScript, C, and C++ — and all five must print byte-identical results, checked mechanically, not claimed.

If five independent implementations agree down to the last byte, the game can’t favor the house on one platform and rob it on another. A disagreement isn’t smoothed over — it stops the line. The refusal is the guarantee.

The code is open source on GitHub, with a paper in the repository describing the method and an operator one-pager for anyone running games. It is dual-licensed: free under AGPL-3.0, or a commercial license from the lab.

Fair outcomes you can prove. Rules you can prove. Both, or neither.

ExactOdds is a protocol for provably-fair gaming with two halves: commit-reveal seeds (the outcome was fixed before your bet) and the exactness law (the game program produces byte-identical output on every target seat — Python, JavaScript, TypeScript, C, C++ — or the program is refused). Today’s “provably fair” proves only the outcome. ExactOdds proves the rules too: the program an auditor gates is the only program that can pass, so a house can’t run different rules in production than the ones it showed the auditor.

What’s here

• games/ — four reference games (provably-fair-dice.exactodds, provably-fair-coin-flip.exactodds, provably-fair-roulette.exactodds, provably-fair-crash.exactodds) and fifteen casino rule packs (casino-bonus-wagering.exactodds, casino-poker-rake.exactodds, casino-sportsbook-settlement.exactodds, casino-affiliate-revshare.exactodds, casino-responsible-limits.exactodds, casino-slots-payline.exactodds, casino-progressive-jackpot.exactodds, casino-tourney-points.exactodds, casino-cashback.exactodds, casino-aml-structuring.exactodds, casino-referral-bonus.exactodds, casino-comp-points.exactodds, casino-rtp-audit.exactodds, casino-raffle-draw.exactodds, casino-baccarat-settle.exactodds). Short, readable, deterministic: seeds in, result out. All money math is integer cents — no floats anywhere.
• gate/ — the exactness gate runner (run-gate.sh), golden fixtures (fixtures/), and the per-seat gate report (GATE_REPORT.md).
• receipts/ — source-hash receipts from the verified 2026-09-26 runs.
• paper/ — PAPER.md (the full protocol paper), PAPER.pdf, and OPERATOR_ONEPAGER.md (one page for casino operators).
• sdk/js/ — the exactodds npm package: all 35 rule functions as a JS library, generated from the .exactodds sources. npm test replays every audited case against the golden fixtures.
• sdk/mcp/ — the exactodds-mcp package: all 35 rule functions as MCP tools over stdio. npx -y exactodds-mcp in your MCP client config.
• api/ — exactodds-api: POST /v1/<program>/<function> with JSON integers; every answer carries the source_hash of the ExactOdds rules that ran. Dockerfile + fly.toml included.

All three consume the same emitted JS seat, so npm, MCP, and API can never disagree with each other — or with the Python, C, and C++ seats.

Verify a game in 5 steps (players)

You need the game’s source, a SHA-256 tool, and any one of: Python 3, node, or gcc.

1. Get the source. games/provably-fair-coin-flip.exactodds in this repo, or the copy your house publishes.
2. Hash it. sha256sum games/provably-fair-coin-flip.exactodds must equal the source_hash in receipts/provably-fair-coin-flip.receipt.json. If not, that’s a different game — stop.
3. Check the revealed seed. After your round the house reveals its server_seed. echo -n "$server_seed" | sha256sum must match the commitment published before you bet.
4. Re-run the round. Plug the revealed server seed, your client seed, and the round number into the program’s flip function — any seat works; the gate guarantees they all agree. The output must match the result the house reported for your round.
5. Check the receipt. receipts/ holds the gated verdict. Auditors can re-run ./gate/run-gate.sh to reproduce the PASS.

Run the gate (auditors, operators)

./gate/run-gate.sh

This needs the ExactOdds reference compiler. Point it at your build:

PROVABLY_COMPILER=/path/to/cuni ./gate/run-gate.sh

It defaults to ../cuni-langs/target/debug/cuni (the lab tree), then ~/workspace/cuni-langs/target/debug/cuni, then cuni on PATH. For each game it emits all five native seats, runs them, demands byte-identical stdout, writes a fresh source-hash receipt into receipts/, and checks the output against the golden fixtures. Exit 0 means every game passed and no fixture drifted.

Reference

• Full protocol: paper/PAPER.md (also paper/PAPER.pdf)
• Operator summary: paper/OPERATOR_ONEPAGER.md
• Seat-by-seat evidence: gate/GATE_REPORT.md

License

Dual-licensed: AGPL-3.0 (LICENSE.AGPL-3.0) or the SLID PHI LABS LLC Commercial License (LICENSE.COMMERCIAL) at $2,500/yr per operator. See LICENSE and NOTICE.

Copyright (c) 2026 SLID PHI LABS LLC.

What this is not

Not a casino, not a gaming license, no custody of funds, not a randomness source. See §5 of the paper.

Related projects

Project	Role
CuNi	The exactness compiler behind the gate
Agent-Rider	Signed agent identity, spend warrants, receipts
Quikgater	Pay-per-fact web fetch for agents (x402)
AwLPay	Multi-rail agent payments (USDC x402, PayPal sandbox bridge)
agenTill	Drop-in payment box for agent storefronts
TNSSRC	Local lossless compression engine
pulsar	Free local best-path compressor (GPLv3 demo)
TRUSTREAM	Lossless compression for live data streams
Chamber	Two-key JSON sealing for secrets
Slid Phi Labs	The lab

Security issues: see SECURITY.md. Contributing: see CONTRIBUTING.md.

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