Souhail is available for hire

Souhail Mssassi

Verified Expert in Engineering

Blockchain Developer

Marrakesh, Marrakesh-Tensift-El Haouz, Morocco

Toptal member since November 5, 2021

Expertise

Crytographer Code Review System Security Smart Contract Development Decentralized Finance (DeFi)NFT Cybersecurity Python Solidity Ethereum Blockchain Web3.js Node.js

Bio

With more than ten years of experience in cybersecurity as an offensive security engineer specializing in application security, cryptography, and security of decentralized applications, Souhail assisted several organizations in improving their cybersecurity strategy. He is also a blockchain developer in Solidity and Rust, working as a security researcher in the blockchain.

Portfolio

MentorCruise

Blockchain, Solidity, Ethereum, Web3.js, Bitcoin, ERC-20, IT Security

Quantstamp Technologies

Blockchain, Solidity, Web3.js, Fuzz Testing, Non-fungible Tokens (NFT)...

Volmex Labs

Blockchain, DApps, Web3.js, Node.js, Non-fungible Tokens (NFT)...

Experience

Penetration Testing - 10 years
Web Security - 9 years
Smart Contracts - 6 years
Ethereum - 6 years
Ethereum Smart Contracts - 6 years
Solidity - 6 years
Blockchain - 5 years
Solana - 3 years

Preferred Environment

Solidity, Remix IDE, Blockchain, Ethereum, Smart Contracts, Ethereum Smart Contracts, Solana, Decentralized Finance (DeFi), Decentralized Applications

The most amazing...

...thing I've created was a platform for bug bounty programs in blockchain to help companies and startups secure their DApp and Smart Contracts.

Work Experience

Blockchain Mentor

2021 - 2023

MentorCruise

Empowered individuals in making successful career transitions and strengthening their programming skills as a mentor at MentorCruise.
Recognized as a top mentor, showcasing exceptional guidance and support provided to mentees.
Ranked in the top 6% of mentors, demonstrating expertise and a track record of delivering impactful mentorship.

Technologies: Blockchain, Solidity, Ethereum, Web3.js, Bitcoin, ERC-20, IT Security

Security Researcher

2021 - 2023

Quantstamp Technologies

Helped blockchain startups to secure their Smart Contracts.
Created a parsing tool to extract Assembly Solidity code.
Used formal verification to verify to correctness and the security of a Smart Contract.

Technologies: Blockchain, Solidity, Web3.js, Fuzz Testing, Non-fungible Tokens (NFT), Decentralized Finance (DeFi), Decentralized Applications, Blockchain & Cryptocurrency, Cryptography, Cryptocurrency, Decentralized Autonomous Organizations (DAO), Tokenomics, Truffle, Bitcoin, Amazon Web Services (AWS), Ethereum Virtual Machine (EVM), Auditing, Testing, ERC-20, Audits, Payment Solutions, Cybersecurity, IT Security, Code Review, User Authentication, Security

Blockchain Senior Developer

2021 - 2022

Volmex Labs

Integrated perpetual contracts and automated covered call strategy vault for a high yield on ETH at Volmex Labs.
Developed a decentralized on-chain Order Book for efficient and secure trading.
Contributed to VIX-like indices implementation for crypto assets, enabling informed decision-making at Volmex.

Technologies: Blockchain, DApps, Web3.js, Node.js, Non-fungible Tokens (NFT), Decentralized Finance (DeFi), Decentralized Applications, Blockchain Platforms, Blockchain & Cryptocurrency, Cryptography, Decentralized Autonomous Organizations (DAO), Tokenomics, Utility Tokens, Truffle, Bitcoin, Amazon Web Services (AWS), Ethereum Virtual Machine (EVM), Testing, ERC-20, Payment Solutions, Cybersecurity, IT Security

Offensive Security Engineer

2021 - 2021

Halborn

Worked on the audit and risk analysis of vulnerabilities in Ethereum Smart Contracts under Solidity.
Audited and pentested of DApps applications (DEX - DEFI).
Pentested blockchain SDK and blockchain network infrastructure.

Technologies: Web Security, Blockchain, Web3.js, Fuzz Testing, DApps, Non-fungible Tokens (NFT), Decentralized Finance (DeFi), Decentralized Applications, Blockchain & Cryptocurrency, Cryptography, Cryptocurrency, Tokenomics, Utility Tokens, Truffle, Server Security, Amazon Web Services (AWS), Ethereum Virtual Machine (EVM), Cybersecurity, IT Security

Blockchain Instructor

2021 - 2021

EatTheBlocks

Animated webinars about secure code in Solidity Smart Contracts.
Planned and helped Solana with courses and the development of programs.
Helped the community to understand complex and advanced concepts in Solidity and tokens.

Technologies: Blockchain, Solidity, Cryptocurrency, Truffle, Bitcoin, Server Security, Ethereum Virtual Machine (EVM)

Senior Blockchain Developer

2017 - 2021

ShellBoxes

Helped companies to integrate and profit from blockchain technology.
Created different tokens including ERC 20 and ERC 721.
Created whitepapers and also study the tokenomics of a blockchain project.
Developed and linked decentralized applications (DApps) with smart contracts through Web3.js, React, and Vue.
Architectured DApps and implemented design and security patterns.

Technologies: Blockchain, Solidity, Rust, Tokenization, Smart Contracts, Web3.js, DApps, Non-fungible Tokens (NFT), Decentralized Applications, Python, Blockchain & Cryptocurrency, Cryptography, Cryptocurrency, Decentralized Autonomous Organizations (DAO), Vue, Tokenomics, Truffle, System Design, Server Security, Ethereum Virtual Machine (EVM)

Senior Security Engineer

2013 - 2019

Societe Generale

Analyzed solutions and tools for the integration of DevSecOPs into the development cycle.
Audited mobile banking system applications including risk analysis, infrastructure audit, implementation of recommendations, and support to comply with Moroccan and European regulations.
Tested the security of Java web applications including writing reports and setting up an action plan to correct the vulnerabilities found.
Established a reference for the methodology of pentesting.

Technologies: Web Security, Penetration Testing, Node.js, Python, System Design, Server Security, Reverse Engineering

Experience

Formal Verification in Smart Contracts

Formal program verification provides a mathematical framework for strengthening confidence in software's correctness. The majority of approaches to program verification are either completely automated and establish only weak features or are labor hard to implement manually; few aim accurately represent machine code.

I created a framework that ensures the correctness and security of the Smart Contracts using mathematical expressions.

Volmex

https://volmex.finance/

Volmex is a protocol for tokenized volatility built on Ethereum. The protocol enables VIX-like indices for crypto assets and trading functionality powered by Ethereum. I worked as a blockchain senior developer and helped Volmex integrate perpetual contracts and vault, a new product that automates a covered call strategy to earn a high yield on ETH. The vault runs a covered call strategy and sells out-of-the-money calls every week.

TraceChain

Led the development of a decentralized supply chain solution on the Ethereum blockchain using Solidity. Implemented smart contracts to ensure transparent and tamper-proof tracking of goods throughout the supply chain, enhancing accountability and reducing fraud.

PropToken

Designed and implemented a blockchain-based tokenization platform for a real estate company. Developed smart contracts to tokenize property assets, enabling fractional ownership and facilitating the seamless and secure transfer of ownership on the Ethereum network.

DeFiLink

Collaborated with a financial technology company to integrate decentralized finance (DeFi) protocols into their infrastructure. Implemented smart contracts and integrated protocols such as lending platforms, decentralized exchanges (DEXs), oracles, and liquidity pools, enhancing the company's offerings and providing users with decentralized financial services.

Education

2019 - 2021

Ph.D. Degree in Computer Science

UCA - Morocco

Certifications

MAY 2023 - PRESENT

Certified Ethereum Expert

Blockchain Council

MAY 2023 - PRESENT

Certified Blockchain Security Professional™

Blockchain Council

Skills

Libraries/APIs

Web3.js, Node.js, Binance API, Vue

Languages

Solidity, Rust, Python

Frameworks

Truffle

Platforms

Blockchain, Ethereum, Blockchain Platforms, Amazon Web Services (AWS)

Industry Expertise

Cybersecurity

Paradigms

Fuzz Testing, Testing, Penetration Testing

Other

Smart Contracts, Ethereum Smart Contracts, Solana, Web Security, Tokenization, Non-fungible Tokens (NFT), Decentralized Finance (DeFi), Decentralized Applications, Blockchain & Cryptocurrency, Blockchain Game Development, Cryptography, Cryptocurrency, Decentralized Autonomous Organizations (DAO), Server Security, Reverse Engineering, Ethereum Virtual Machine (EVM), Auditing, ERC-20, Web3, Audits, IT Security, Code Review, User Authentication, Security, DApps, Tokenomics, Utility Tokens, Bitcoin, System Design, Payment Solutions, Formal Verification

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