RPSX
Rock Paper Scissors Onchain x402
The problem RPSX solves
The Problem It Solves
Onchain games are technically decentralized but practically unplayable.
Even simple games require multiple onchain transactions for setup, moves, and settlement. This results in:
$3–$5 in gas fees to play a $1 game
Slow gameplay due to block confirmations
Repeated wallet popups that break UX
Because of this, real-time and casual onchain gaming has failed to gain adoption.
How RPSX Solves It
RPSX removes blockchain friction from gameplay.
Players deposit once using x402 and then play multiple games instantly.
Games are played offchain in real time and settled onchain in batches, reducing per-game cost to a few cents.
This enables:
Real-time gameplay with no signing during play
Micro-stake games that are economically viable
A web-like UX with onchain security
Why This Matters
RPSX demonstrates a practical pattern for consumer crypto:
Offchain interaction
Onchain custody
Batch settlement
x402-powered payments
This approach makes onchain gaming usable for real users and can be extended to many simple games beyond Rock Paper Scissors.
Challenges I ran into
Real-Time Gameplay vs Onchain Finality
Onchain execution is too slow for interactive games, but fully offchain games break trust.
Fix:
I split the system into offchain execution + onchain settlement.
Moves are exchanged over WebSockets and each round is finalized via mutual signed messages. The contract only verifies signatures and applies payouts during batch settlement.
Gas Costs at Micro-Stakes
Per-game settlement made small-stake games economically impossible.
Fix:
I implemented batched settlement where multiple signed game results are committed in a single transaction. Gas is amortized across players, pushing per-game costs down to cents while keeping funds non-custodial.
Wallet UX Friction
Signing transactions per move kills retention.
Fix:
I used x402 for balance-based payments. Players deposit once, play many games without signing, and withdraw later. x402 removes wallet prompts from the critical path while keeping payment logic verifiable.
Technologies used
Cheer Project
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