Anchor Based Coinflip Game

[Kali-Decoder]

🪙 Coinflip Game (On-chain Randomness)

🚀 Overview

This PR introduces a Coinflip betting game built on Solana using Anchor.
Users place a wager and guess Heads/Tails, and the outcome is determined using verifiable on-chain randomness.

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✨ Features

• Initialize player state with wager config
• Users place bets with a coin flip guess
• Funds are securely held in an escrow account
• Fair settlement with win/lose logic
• Winners receive 2x payout, losers lose wager
• Safe SOL transfers using CPI

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🎲 Randomness

• Integrated Switchboard On-Demand Randomness
• Uses RandomnessAccountData to fetch verifiable randomness :contentReference[oaicite:0]{index=0}
• Ensures:
  • No manipulation by owner or user
  • Result tied to a specific slot (commit-reveal style)
  • Fair and transparent outcome generation

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🧪 Gameplay Flow

1. User initializes account
2. Places a bet with a guess
3. Randomness is committed
4. Flip is settled using revealed randomness
5. Rewards distributed if guess is correct

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✅ Outcome

• Fully on-chain, trustless coinflip game
• Verifiable randomness ensures fairness
• Ready for UI integration and scaling

[aarjn]

please remove the dice pool game program from this. since there is already an open PR for it

[Kali-Decoder]

I check Closed pRS also there is not dice pool like game pr or folder
And this is Coinflip PR

[aarjn]

I mean this. Its better to have a single program in a PR.

[Kali-Decoder]

I have maintained separate branches in my fork because both repositories represent different simple game implementations.

Keeping them in different branches helps ensure proper organization, avoids conflicts, and allows independent development and tracking for each game.

[aarjn]

Keeping them in different branches helps ensure proper organization, avoids conflicts, and allows independent development and tracking for each game.

yeah, you are right. that's why i asked to remove anchor-dicepool-game from this PR. since there is #12 for it

[Kali-Decoder]

Works I Closed Dice pool PR

[aarjn]

No need to close it. I said remove anchor-dicepool-game from this PR. Keep 2 PR for 2 Programs. Its fine for now I will review from this PR itself.

[Kali-Decoder]

Works Review Let me know

[aarjn]

test cases are failing

(Use `node --trace-warnings ...` to show where the warning was created)


  sb-randomness-coinflip
    1) "before all" hook for "Initializes player account"


  0 passing (5ms)
  1 failing

  1) sb-randomness-coinflip
       "before all" hook for "Initializes player account":
     TypeError: Cannot read properties of undefined (reading 'load')
      at /Users/arjunc/Documents/solana/solana-programs-list/anchor-coinflip/tests/coinflip.ts:30:39
      at Generator.next (<anonymous>)
      at /Users/arjunc/Documents/solana/solana-programs-list/anchor-coinflip/tests/coinflip.ts:31:71
      at new Promise (<anonymous>)
      at __awaiter (tests/coinflip.ts:27:12)
      at Context.<anonymous> (tests/coinflip.ts:29:21)
      at processImmediate (node:internal/timers:505:21)



error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.