Real tokens, real reserves, real audit trail — no vaporware.

Blockchain & Smart Contract Development

A token is only as trustworthy as the code that guards it and the mechanism that anchors it to something real. I have shipped the Vetra USD-backed stablecoin on Polygon with Chainlink Functions verifying reserves in real time, an AMM-style DEX on Solana with Anchor, and an ESG plastic-credit protocol with Stripe Split for commission distribution. Every contract has a stop button before launch, not after the first incident.

Why it matters

Blockchain projects fail publicly. A missing pausable modifier, a wrong access role, an unverified oracle feed — any one of them turns into a headline. The premium is not in writing the contract, it is in writing the surrounding controls that make the contract survive a bad day.

What you get

  • →Solidity ERC-20 / ERC-721 with pausable, ownable and role-based access as design defaults.
  • →Chainlink Functions and Chainlink Automation for verifiable off-chain data and scheduled on-chain jobs.
  • →Polygon PoS as the default L2 for token launches (low fees, real users, EVM-compatible tooling).
  • →Solana + Anchor for high-throughput protocols (DEXes, order books, in-game economies).
  • →SPL tokens and Jupiter Aggregator integration for real Solana DeFi liquidity.
  • →Stripe Connect / Stripe Split for automated real-world commission distribution alongside on-chain flows.
  • →Full test coverage before deployment (Hardhat / Foundry for EVM, Anchor tests for Solana).
  • →Deployment scripts, verified contracts on Etherscan / Solscan, and a written incident response plan.

Stack

  • Solidity
  • Hardhat
  • Foundry
  • OpenZeppelin
  • Polygon PoS
  • Chainlink Functions
  • Solana
  • Rust
  • Anchor
  • SPL Tokens
  • Jupiter Aggregator
  • ethers.js
  • The Graph
  • Stripe Connect

Delivered projects using this stack

Impact Processor CSR26

An ESG plastic-credit protocol needed dynamic weekly pricing and a 5/45/50 vesting rule on-chain. Stripe Split handles automated commission distribution.

Spraicoin Token + Presale

A new token needed a smart contract and a presale API wired into the existing site. Full implementation guaranteed API security and correct token interaction.

DexSpeed DEX on Solana

Traders leave when the price moves between the click and the fill. Sub-second execution on Solana keeps the order book worth using.

Ethereum DEX Scanner

Real-time swap events on Uniswap V2 needed a Node.js scanner. The Graph subgraph + ethers RPC log scanning fed analytics and alerts.

Frequently asked questions

Is Ustym Kushnir the creator of a real stablecoin?+

Yes. Vetra (VTR) is a USD-backed stablecoin deployed on Polygon PoS with Chainlink Functions verifying reserves in real time. It is not a hype token — it exists as a production reference of how a reserve-backed asset can be structured and how the reserve mechanism can be made publicly verifiable.

Do you deploy on mainnet, testnet, or both?+

Both, depending on the phase. Every contract is first audited against a test suite on Hardhat / Foundry, then deployed to a public testnet (Amoy for Polygon, devnet for Solana) with client-facing end-to-end tests, then promoted to mainnet with a written deployment checklist. The client always signs the mainnet deployment transaction — nobody else touches those keys.

Do you audit contracts written by other developers?+

Yes, as a defined-scope engagement. A code review + threat model + written report typically takes 5–10 business days depending on the surface area. This is separate from writing the contract myself — the audit engagement is priced and delivered as a standalone.

Will you build a memecoin / rug / anonymous project?+

No. Every engagement requires a legal counterparty, a stated real-world use case, and a contract with a stop mechanism. This is a permanent policy — reputation compounds, and reputation is the whole business.

Ready to start?

Send a written brief with the business problem to solve. I come back with a concrete plan against that document, in the client's language.

Contact →

Other services

Custom Booking & Scheduling System Development

Own the appointment engine your business already runs on.

Operations Automation — Replace Spreadsheets, Paper and Manual Workflows

Software the team stops having to think about.

AI CRM & WhatsApp Assistant Development

AI put inside the process that already runs, not on top of it.

Security Engineering & Incident Response

Get the attacker out, then make getting back in expensive.

Fintech & Payment System Integration

Money moves correctly, or it does not move at all.

Mobile App Development — iOS, Android, Cross-Platform

Ship to the App Store and Google Play, without the SaaS wrapper tax.