Jean-Loïc Mugnier, Developer in Paris, France
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Jean-Loïc Mugnier

Verified Expert  in Engineering

Blockchain Developer

Paris, France
Toptal Member Since
October 7, 2022

Jean-Loïc is an ambitious, passionate French-Brazilian software engineer specializing in cybersecurity and cryptography. He has a background in computer science, an MBA in business management, and professional experience at Accenture, Binance, and BNB Chain, where he was the Web3 cybersecurity team lead and Cybersecurity Working Group coordinator at Campus Cyber and Niftag, a startup he founded.


Web3, Smart Contracts, Auditing, Architecture
Auditing, Python, Smart Contracts, JavaScript, Blockchain...
Campus Cyber
Solidity, Git, Blockchain, Non-fungible Tokens (NFT), Web3, Project Management...




Preferred Environment

Git, Hardhat, Auditing, DevSecOps, Solidity, Cloud, Distributed Ledger Technology (DLT), Web3, IT Project Management, Agile Project Management

The most amazing...

...program I've delivered was a public cloud migration for an IT company leader in the travel industry that impacted over 2,000 developers.

Work Experience

Web3 Security Lead

2022 - PRESENT
  • Crafted the Web3 security framework, akin to ISO standards, in collaboration with Web3 security experts like Certik, Slowmist, and Peckshield. These guidelines served as a unified basis for safeguarding all projects within the BNB Chain ecosystem.
  • Initiated a weekly security scanning program to enhance the safety of all projects within the ecosystem by running weekly reports on the vulnerabilities detected and the best practices being followed.
  • Oversaw the integration of the auditing team to adhere to the established standards.
  • Developed a roadmap for tooling advancement, focusing on identifying newly detected vulnerabilities.
  • Launched a cybersecurity initiative to disseminate knowledge and foster community awareness about cybersecurity threats and their corresponding solutions with BNB Chain cybersecurity partners.
  • Harmonized roadmap and priorities with key management figures (BNB Chain leader and Binance CISO) despite divergent viewpoints.
Technologies: Web3, Smart Contracts, Auditing, Architecture

Smart Contract Security Engineer

2022 - PRESENT
  • Performed studies on historical hacks and vulnerabilities found in protocols.
  • Conducted competitors analysis in terms of features and technologies.
  • Developed on top of Slither, a static code analysis tool allowing us to detect vulnerabilities. Implemented newly discovered vulnerabilities from hack reports.
  • Created new tools to scan all the BNB Chain projects above $200,000 in total value locked.
  • Developed a tool for simulating transactions and protecting end users from scams.
  • Created the 1st tool designed for conducting penetration testing on smart contracts.
  • Participated in an AMA session to discuss cybersecurity for the BNB Chain.
Technologies: Auditing, Python, Smart Contracts, JavaScript, Blockchain, Non-fungible Tokens (NFT), Web3, Web Security, Hardhat, Git, DevSecOps, Solidity, Software Engineering, Agile Project Management, IT Project Management, Back-end Development, Architecture

Working Group Coordinator

2021 - PRESENT
Campus Cyber
  • Led the creation and writing of the Blockchain Catalog of Attack.
  • Presented our work at the International Forum of Cybersecurity (FIC).
  • Drove workshops for cybersecurity companies such as Orange Cybersecurity.
  • Led my team in conducting a comprehensive analysis of smart contract threats and solutions, utilizing the ANSSI cybersecurity analysis framework.
  • Coordinated a conference featuring industry leaders from both Web2 and Web3 sectors.
Technologies: Solidity, Git, Blockchain, Non-fungible Tokens (NFT), Web3, Project Management, Web Security, Hardhat, Architecture

CTO | Founder

2021 - PRESENT
  • Developed our MVP application used to get our first clients.
  • Defined the roadmap features based on clients' needs and interests.
  • Created our recruiting strategy based on our roadmap.
  • Pitched to venture capital (VC) and business angels (BA) investors on our long-term strategy to raise capital.
Technologies: Feature Roadmaps, Product Roadmaps, Budget Management, Recruiting, Software Engineering, Blockchain, Non-fungible Tokens (NFT), Web3, Web Security, Hardhat, Git, Linux, DevSecOps, Solidity, Agile Project Management, Back-end Development, Smart Contracts, Architecture, Amazon Web Services (AWS)

Senior Software Engineer

2017 - 2021
  • Delivered a public cloud migration program for the Amadeus department.
  • Migrated a proprietary identity and access management (IAM) solution at Axa Go.
  • Managed roadmaps, deliveries, and other internal assets.
Technologies: Java, Angular, DevOps, Cloud, Agile, Docker, Kubernetes, Project Management, Git, Linux, DevSecOps, Software Engineering, Agile Project Management, IT Project Management, Back-end Development, Architecture, Amazon Web Services (AWS)

Niftag is a solution for authenticating physical goods with a simple smartphone tap. The solution relies on IoT devices installed in the products, a smartphone app, and an integration with blockchain NFTs. As the CTO and founder, I developed the project's tech stack.


Java, Solidity, Python, JavaScript


DevOps, Agile, DevSecOps, Agile Project Management


Blockchain, Linux, Docker, Kubernetes, Ethereum, Amazon Web Services (AWS)


Cloud, Distributed Ledger Technology (DLT), Software Engineering, Back-end Development, Non-fungible Tokens (NFT), Web3, Web Security, Feature Roadmaps, Product Roadmaps, Smart Contracts, IT Project Management, Architecture, Auditing, Budget Management, Recruiting


Hardhat, Angular, Ionic





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