0xvarius

Senior Solidity & De Fi Protocol Engineer

Senior Solidity and DeFi protocol engineer with 5 years of experience designing, building, and operating production blockchain systems. My work includes collateralized lending, vaults, staking and emissions systems, liquidity integrations, oracle-dependent logic, upgradeable contracts, and multi-chain deployments.

I work across the full protocol lifecycle, from architecture and Solidity development through Foundry testing, TypeScript integrations, deployment, monitoring, and post-launch operations. I am especially comfortable reasoning about liquidations, access control, reentrancy, upgradeability, oracle risk, economic edge cases, and how contracts behave under real market conditions.

I am looking for a senior Solidity or protocol engineering role where I can contribute to DeFi infrastructure, smart contract security, protocol design, integrations, and production reliability. I work well in remote, async teams and am most interested in lending, stablecoins, collateral systems, staking, vaults, and other technically demanding onchain products.


Experience: 5 years

Yearly salary: $174,000

Hourly rate: $90

Nationality: 🇨🇦 Canada

Residency: 🇨🇦 Canada


Experience

Founder & Lead Engineer
MasterBrews
2021 - 2026
Founded and operated a Web3 studio delivering smart-contract systems and blockchain infrastructure across multiple EVM chains and Solana. Expanded the studio's dynamic NFT work from Ethereum to Solana, including hands-on Rust development and technical architecture for Heroes & Villains: Origins. Selected as a pilot partner in Chainlink's channel partner program.
Chief Technology Officer
Good Gamer Corp
2020 - 2021
Led technology delivery for daily fantasy sports, poker, and mobile skill-gaming products on a mixed PHP and Ruby stack, managing a small internal engineering and design team alongside multiple third-party vendors. Worked directly with the CEO and external auditors on technical processes, controls, and readiness requirements that supported the company's subsequent TSX Venture listing.
Chief Technology Officer & Co-Founder
Rize.com
2019 - 2020
Co-founded and architected a pre-launch digital-health and online-pharmacy platform focused primarily on men's health, serving as a hands-on Go developer. Built patient intake questionnaires, consumer product flows, and an internal CMS and operations portal designed around HIPAA privacy and security requirements.
Chief Technology & Information Officer
jClub.com
2016 - 2020
Owned the consumer and vendor e-commerce platforms, technical operations, analytics, and engineering execution for a jewelry-focused flash-sales business that later expanded into broader product categories. Managed a six-person engineering team and a Ruby on Rails, MySQL, and AWS platform, while leading email deliverability and marketing technology that helped grow the company from launch to approximately $1 million in first-year revenue.
Chief Technology & Information Officer
Choxi.com (formerly Nomorerack.com)
2011 - 2016
Owned technology from the company's early stage through roughly five years of rapid growth to nearly $1 billion in cumulative gross sales, scaling consumer and vendor platforms for high-volume e-commerce operations. Architected the PHP consumer platform and later rebuilt the Ruby on Rails vendor portal, supported by MySQL and AWS infrastructure. Managed a peak engineering team of approximately six and maintained reliable platform operations through extreme Black Friday and Cyber Monday traffic periods.
Chief Executive Officer & Founder
Stormshadow S.A.
2008 - 2016
Chief Technology Officer
Mana Internet Solutions S.A. (formerly Wisol Inc.)
2000 - 2008
Built and operated IWantU.com, CashRing.com, and client-hosting infrastructure from the ground up, including an affiliate network serving more than 20,000 members.

Skills

aws
defi
erc-1155
erc-20
erc-4626
erc-721
evm
hardhat
nextjs
node
protocol-engineer
react
rust
smart-contract
tokenomics
typescript
web3
web3js
solidity
english
french
spanish