Freelancer profile translated to English.
Back to original languageAbout Theo
Looking for a Solidity developer?
Need help with smart contracts?
You've come to the right place.
I am a Solidity developer with 6+ years of experience.
I build smart contracts for DeFi and RWAs.
I develop yield vaults and staking.
I build derivative products (options, perps) and cross-chain transfers.
I also develop on-chain fractionalization solutions.
I also built a custom prediction market (parimutuel).
I have worked with Aria, Seedify, and Omnia DeFi.
My code currently secures over $25M in TVL.
I can help you with:
- Scoping your on-chain needs
- Translating financial and mathematical concepts into Solidity
- DeFi and RWA protocol design (AMM, lending, staking, options)
- Upgrade patterns (Diamond, UUPS, proxy)
- Working with external auditors
- Cross-chain with LayerZero (OFT)
- Gas optimization with Solidity and Yul
- Vaults (ERC-4626) and vesting flows
- EIP-712, Permit2, and Merkle tree flows
- Testing with Foundry and Hardhat (unit, fuzz, invariant)
- ERC20, ERC721, and ERC1155 tokens
- Working with other teams to integrate on-chain and off-chain systems.
- Security analysis tools: Slither, Aderyn, Echidna, Mythril
- Writing and testing smart contracts on EVM blockchains
- Fixing risks of reentrancy, access, and oracles
I also use OpenZeppelin, Solmate, Chainlink, and Uniswap.
I mentor junior developers. I manage development from A to Z.
Trust is important to me.
I send a report at the end of each day.
It lists each task in detail, plus any blockers if there are any.
This is how I secured over $25M in TVL.
Have a project?
Contact me by message
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Solidity Engineer, Solidity Developer, Smart Contract Developer, Senior Solidity Engineer, Protocol Engineer, Protocol Developer, DeFi Engineer.
Soldity, Soldity Developer, Smart contract Enginer, Smartcontract Engineer.
French
Native or bilingual
English
Native or bilingual
German
Basic
Can work on-site
Paris (up to 50km), Strasbourg (up to 50km), Marseille (up to 50km), Toulouse (up to 50km), Lyon (up to 50km)
Experience
- Aria LabsSenior Solidity EngineerTECHApril 2025 - Today (1 year and 2 months)New York, United StatesAria Protocol makes music intellectual property (IP) liquid through tokenization.In Sep 2025, Aria raised $15M from Polychain, Neoclassic, and Story Foundation, after raising $10.95M on StakeStone in Feb 2025.Aria has 10 employees, 4 engineers, and has tokenized 47 songs. J. Bieber's "Peaches" has already generated 1.7 billion Spotify streams.I joined Aria as a B2B Solidity developer. I design and deploy the on-chain stack on Story and co-pilot audits with Pashov, Guardian, and Halborn.The team:
- 1 Solidity developer
- 1 front-end, 1 back-end
- 1 CTO (full-stack), 1 designer.
My responsibilities:- Development of the DeFi vault contract (ERC-4626).
- Deployment of cross-chain tokens on Story and BSC (LayerZero OFTs).
- Development of vesting contracts (native, ERC-20, ERC-1155).
- Development of the royalty distribution system on each stake.
- Fractionalization of intellectual property on-chain.
- Collaboration with front-end and back-end teams to link contracts (TypeScript).
- Management of on-chain deployment: APL & DeFi Vault on June 25, 2025.
- Writing unit, integration, and fuzz tests.
- Management of internal and external audits.
- Gas optimization with Solidity and Yul.
Results delivered to the protocol:- $10M TVL in staking and OFTs.
- $10M IP fractionalized via Story Protocol.
- $572.1k royalties distributed over 9 months.
- 12,000 transactions, 2,500 stakers, 3,000 holders.
- 85% of supply staked for 10 months.
- 8 contracts delivered, with 90% test coverage.
Some protocol links:- Assets: ariaprotocol.xyz/assets
- Social audit: 0x73d6000b8b87bea28a99AED83c2B62a7Ea35ac477
- Royalties hook: 0x271346Edfa1Bd4e91F0968ac0e47Af9dede1769A
Technical context:- Solidity
- Yul/Assembly
- Foundry/Hardhat
- TypeScript
- OpenZeppelin
- LayerZero
- Story Protocol/BSC
- ERC-4626
- NFT (1155, 721)
- EIP-712
- fuzz/invariant tests
- Slither/Aderyn
- TDD
- PolaritySenior Solidity EngineerBANKING AND INSURANCEJune 2023 - April 2025 (1 year and 10 months)Paris, FrancePolarity is a DeFi protocol. Trading calls and puts on wETH and wBTC. Peer-to-pool AMM logic with three assets: wETH, wBTC, USDC. When the protocol loses, traders win. When it wins, traders lose. Pashov audited the protocol.I joined the team as a Solidity engineer. I led the protocol development and mentored a junior Solidity developer.The team:
- 2 Solidity engineers,
- 1 full-stack,
- 1 designer,
- 1 product manager / founder.
My responsibilities:- Development of the Options AMM on Berachain.
- Design inspired by GMX, LVL Finance, and Hegic.
- Addition of an on-chain Black-Scholes model for premium pricing, with pull oracles (Stork, Block Scholes).
- Gas optimization in the AMM for liquidity deposits and rewards (Fenwick).
- Development of a rebalancing logic based on Uniswap v3 (Kodiak), with dynamic fees.
- Development of the lending pool. Yield curves define the rates.
- aTokens rebase to track lender gains and borrower debt.
- Internal and external audit (Pashov).
- Writing unit and fuzz tests on smart contracts.
- Collaboration with front-end and back-end teams to link on-chain and off-chain systems.
- Development and delivery management with ClickUp.
Results I contributed to on the former Berachain testnet:- Approximately $300M in notional interest.
- 2,000 unique wallets.
- 10,000 options contracts opened.
- Audited by Pashov Audit Group.
- Mentored a junior Solidity developer to autonomy.
Technical context:- Solidity
- Yul / Assembly
- Foundry / Hardhat
- TypeScript / Ethers.js
- Openzeppelin / Solmate / Solidstate
- Chainlink
- LayerZero
- Uniswap v3
- ABDKMath / PRBMath / Murky
- ERC-2535 Diamond Proxy
- EIP-712
- fuzz / invariant / differential / unit tests
- Slither / Mythril
- GitHub Actions
- TDD
- Scrumban
- Notion / ClickUp
- SeedifySolidity DeveloperTECHJanuary 2023 - November 2024 (1 year and 9 months)Victoria, SeychellesSeedify is the #1 Web3 Gaming launchpad. It has delivered over 50 projects with the highest average IDO ROI in the market. Raised $10M from LDA Capital. 800k followers on Twitter and over 100 employees.I joined the Solidity team as a Solidity developer. I built the core smart contracts (launchpad, staking, farming). Multi-chain: BSC, Polygon, and Fantom. Secured $15M in TVL.The team:
- 1 Solidity developer,
- 3 front-end, 3 back-end, 1 full-stack,
- 1 product manager, 1 designer.
My responsibilities:- Smart contract design (launchpad, staking, lottery...).
- Pair programming and code reviews with another developer.
- Coordination with the technical lead for verifications.
- Managing token allocation and NFT purchase/mint in one step.
- Securing NFT reveal date with data hashing.
- Implementing cross-chain sales (LayerZero).
- Reducing gas costs for whitelisting (Merkle tree, Permit2, YUL).
- Using Chainlink for random number generation.
- Performing advanced security tests (fuzz, differential, invariant, mutation, symbolic execution).
- TypeScript scripts for various integrations (Merkle trees, EIP-712/Permit2, Snapshot DAO).
- Collaboration with front-end and back-end teams.
- Aggressive gas optimization on the lottery.
Results delivered to Seedify:- $15M TVL secured in production.
- 50+ IGOs delivered in production.
- Highest average ROI in Web3 among launchpads.
Some useful links:- IGO & Lottery (Diamond): * Seedify ROI ranking:
Technical context:- Solidity
- Yul / Assembly
- Foundry / Hardhat
- JavaScript / TypeScript / Ethers.js
- OpenZeppelin / Solidstate
- Chainlink
- LayerZero
- Uniswap v3 / Permit2
- ABDKMath/PRBMath
- ERC-2535 Diamond Proxy
- EIP-712
- fuzz / invariant / differential / unit tests
- Merkle tree
- Slither/SuMo/Manticore
- GitHub Actions
- TDD
- Scrumban
- Jira
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Education
- DUT InformatiqueIUTBM Belfort2020L’IUT Nord Franche-Comté est un institut universitaire de technologie public. Il propose un parcours de développement logiciel sur le campus de Belfort. Le département Informatique (BUT Informatique) forme des profils IT depuis des décennies. Il délivre un diplôme de niveau licence en trois ans, reconnu dans toute la France. Parcours phare : Développement d’applications : conception, réalisation et validation. Il prépare les étudiants à concevoir, développer, tester et déployer des solutions logicielles. Des applications web et mobiles aux systèmes d’entreprise. Le département accueille environ 96 nouveaux étudiants chaque année. Il travaille en étroite collaboration avec des entreprises technologiques locales et nationales grâce aux stages et à l’alternance. J’ai suivi ce programme avec une spécialisation en développement d’applications logicielles.
Certifications
- Advanced Solidity: Yul and AssemblyUdemy2021