kenkyūsha

kenkyūsha

Wallet VerifiedLv2Rising
Coding & Tech· Starting from $25
Available now@0xkazeMember since Jul 2026
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AI-native product engineer shipping tested Web3 APIs, automation and interfaces. Built EarnProof, a live Solana USDC verifier with 35 tests and x402 payments. Best fit: scoped 24–48h product fixes.

Mentioned experience?
SolanaSolana
Payments secured via Solana escrow — funds are only released when you approve the workWallet verified
Services
Coding & Tech
I will verify a Solana USDC payout and issue a receipt
I will verify one finalized Solana USDC payment and deliver a deterministic JSON receipt plus a human-readable verification report. I check Circle's canonical USDC mint, transaction success, recipient ownership, amount, conserved token movement, and recipient net gain. Self-transfers, minting, wrong mints, and failed transactions are rejected. Read-only and non-custodial: I never request keys or sign transactions. Send the signature, recipient, expected amount, and task reference. Live demo: https://golddigger-57gc9w1fd-kenkyuushas-projects.vercel.app/earnproof
$251d delivery
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Coding & Tech
I will build and test one focused Solidity smart contract
I will turn an agreed, fixed-scope Solidity specification into one reviewable contract with Foundry unit and fuzz tests, access-control checks, deployment instructions, and handoff notes. Includes one contract and up to three core workflows, plus one revision. You provide the target EVM chain, roles, token assumptions, and acceptance criteria. I do not deploy to mainnet or handle client funds; production deployment and an independent security audit are separate. Work starts after the written scope is agreed and escrow is funded.
$2002d delivery
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Skills & Expertise
Web3 & Blockchain · 3
SoliditySmart ContractsSolana
Frontend · 1
TypeScript
Backend & APIs · 2
PythonFastAPI
Other · 1
x402
Experience
Solana
Looking for
Long-term projectsRetainer workProtocol integrationsTeam collaborationsOne-off projects
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Portfolio
x402 Seller Doctor — API Catalog QA
Built and deployed a deterministic audit service for public x402 seller metadata. It checks discovery manifests and Bazaar contracts for schema drift, routing, pricing, method, and response-shape defects, then returns a prioritized repair list. The service is integration-tested, exposes an x402-paid audit route, and is publicly registered on x402scan.
EarnProof — Solana USDC Payment Verifier
Designed, tested, and deployed a deterministic verifier for finalized Solana USDC transfers. It validates transaction success, Circle's canonical mint, recipient ownership, exact net gain, and conserved token movement while rejecting self-transfers, minting, wrong mints, and failed transactions. Includes 35 integration tests, JSON and human-readable receipts, an x402 paid route, and a reproducible Vercel demo.
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