SteamLink

One Signature. A Whole Game. Fully Onchain.

SteamLink ships fully onchain games on Base, powered by its game engine Nexus — a player signs once and plays forever: every move gasless, every payment bounded onchain, every outcome provably fair.

The Problem

Today's onchain games are fundamentally broken from a user-experience perspective.

Players face:

• Endless wallet popups

• Gas fees on every move

• Leaking hidden information

• Manipulable randomness

• Fragmented payment systems

For developers, the situation is even worse.

Every game team repeatedly rebuilds:

• Delegation infrastructure

• Transaction relaying

• Payment settlement

• Randomness systems

• Hidden-state mechanics

As a result, very few projects ever ship games that are truly fully onchain.

The Solution

SteamLink reduces the entire problem to a single primitive:

One Delegation.

When a player joins a game room, they sign a single ERC-7710 delegation containing two permission groups:

Gameplay Permissions

Authorizes future game actions.

Budget Permissions

Defines strict onchain spending limits.

After this single signature:

• Every move becomes gasless

• No additional wallet confirmations appear

• Payments execute automatically within predefined limits

• The player never signs again during gameplay

Developers simply define:

• Data (tables)

• Logic (systems)

SteamLink handles everything else:

• Delegation execution

• Transaction relaying

• Secret state management

• Randomness

• Settlement

How It Works

Infinite Moves From One Signature

A player signs once.

The relayer continuously redeems the delegation through redeemDelegations() and pays transaction gas using stablecoins.

The player:

• Pays no gas

• Signs nothing else

• Experiences gameplay similar to Web2

Money With Guardrails

SteamLink integrates x402 payments directly into gameplay.

Entry fees, purchases, and in-game transactions are executed through delegation redemption while remaining bounded by onchain budget caveats.

This means:

• Spending limits are enforced onchain

• Relayers cannot overspend user funds

• Payments remain fully automated

Secret State

Games require hidden information.

SteamLink uses Lit Protocol to seal private state such as:

• Card hands

• Fog-of-war information

• Private inventories

• Hidden strategies

Data can only be revealed to the authorized player through onchain access conditions.

Provable Fairness

Random events settle directly onchain.

Examples include:

• Card shuffles

• Dice rolls

• Loot generation

• Match outcomes

Every random result is publicly verifiable.

Optimistic UX, Onchain Truth

Moves execute instantly in the interface.

The system later reconciles against Base transactions and relayer confirmations.

If a move fails, developers receive typed errors such as:

• NOT_YOUR_TURN

• BUDGET_EXCEEDED

• INVALID_MOVE

What We Built

SteamLink SDK

Published as:

npm i @steamlink/core @steamlink/react

Packages include:

Benefits:

• Type-safe game definitions

• Compile-time validation

• Provider abstraction

• Minimal blockchain complexity

Two Complete Games Live On Base

UNO

A full 108-card implementation featuring:

• Buy-ins

• Hidden hands

• Gasless gameplay

• Onchain winner settlement

Monopoly

A complete 40-space implementation featuring:

• Property ownership

• Rent payments

• Buy-ins

• Pot settlement

• Onchain payouts

Both games have been played end-to-end:

First move → Last move → Onchain payout

Autonomous AI opponents also participate using their own delegations and play entirely gaslessly.

Technology Stack

MetaMask Smart Accounts Kit

ERC-7710 Delegations

1Shot Permissionless Relayer

• Stablecoin gas payments

• EIP-7702 EOA upgrades

• Delegation redemption

Lit Protocol

• Sealed state

• Private game information

Onchain Randomness

• Verifiable fairness

• Public settlement

x402

• Automated payment rails

• Budget-constrained spending

Base

• Settlement layer

• Transaction execution

Why It Matters

SteamLink transforms fully onchain game development from a months-long cryptography project into an afternoon of game design.

Instead of:

• Wallet popup after wallet popup

• Custom relayer infrastructure

• Trust assumptions around payments

Developers get:

• One signature

• Gasless gameplay

• Bounded spending

• Verifiable settlement

• Production-ready infrastructure

Most importantly:

Two finished games prove the entire stack works today.

Not simulations.

Not mockups.

Not slides.

Real players.
Real transactions.
Real payouts.

Why Not Existing Onchain Engines?

Most existing engines focus on storing game state onchain.

SteamLink focuses on something more important:

The Player.

Nexus provides:

• Gasless interaction flows

• Delegated execution

• Bounded payment rails

• Secret-state infrastructure

• Settlement guarantees

It is not another storage framework.

It is the experience layer required for real onchain applications.

Beyond Board Games

The SteamLink primitive extends far beyond games.

The combination of:

Single Delegation + Bounded x402 Payments

enables any application where users repeatedly act and pay without re-signing.

Examples include:

• Trading card games

• Strategy games

• Prediction markets

• Multiplayer economies

• AI agent competitions

• Paid social experiences

• Turn-based marketplaces

Anywhere users repeatedly interact with smart contracts, SteamLink removes wallet friction.

Verification

SDK

npm i @steamlink/core @steamlink/react

Onchain Activity

Every action is a real transaction on Base:

• Entry fees

• Delegation redemptions

• Gameplay actions

• Winner payouts

The player remains the delegator.

The relayer pays gas.

The protocol enforces spending limits.

Proof

SteamLink includes:

• Full UNO implementation

• Full Monopoly implementation

• Complete gameplay recordings

• Onchain settlement transactions

From first move to final payout.

SteamLink

Powered by the Nexus Engine

Live on Base.

SDK available on npm.

One signature → an entire game.

All development, integrations, testing, and deployment were completed entirely during the hackathon period. No pre-built product or functionality existed before the event.

We are actively looking for Grants and fund raising to make it the game builder for EVM ecosystem