Sentnl

Sentnl is a blockchain security audit firm founded in 2019 and registered in England and Wales (Company No. 12906474). Operating under the tagline "Working to make Web3 a safer place," Sentnl provides professional security auditing services to blockchain projects, protocols, and decentralised applications across multiple chains including Ethereum (EVM), EOS, WAX, Telos, and others.

Core Products/Services

Sentnl offers six core security service lines, all delivered by an in-house team of experienced blockchain security experts and auditors:

• Smart Contract Audit – Comprehensive line-by-line code review of smart contracts prior to deployment, covering vulnerability identification, functional testing, and security assessment across any smart contract language or platform.
• Blockchain Protocol Audit – Deep review of the underlying protocols of a blockchain network, examining core infrastructure for vulnerabilities, bugs, and weaknesses that could compromise integrity.
• EVM Audit – Specialised audit for Ethereum Virtual Machine-compatible chains, assessing smart contracts and decentralised applications (DApps) for security, reliability, and gas optimisation.
• Advanced Penetration Testing – Sophisticated cybersecurity assessment using simulated cyberattacks in a controlled environment to uncover vulnerabilities in Web3 projects and blockchain applications.
• Fuzzing – Automated testing technique that bombards smart contracts with unexpected and random inputs to expose hidden vulnerabilities and edge-case exploits that standard audits may miss.
• Tokenomics Audit & Design – Analysis and optimisation of a token's economic model, covering distribution, supply mechanisms, utility, and market positioning for both new and existing tokens.

Key Strengths

Sentnl combines manual line-by-line code review with state-of-the-art automated tooling, including their industry-noted fuzzing capabilities. The team has over seven years of demonstrated expertise in blockchain security. Their audit process follows a structured five-step methodology: initial consultation, code review and testing, security assessment, reporting and discussion, and remediation and finalisation. All findings are delivered in clear, detailed reports with actionable recommendations.

Notable Clients/Projects

Sentnl has audited projects for major organisations in the blockchain sector, including:

• EOS Network Foundation (xyz-system contract, March 2025)
• Ultra (ultra-bridge-eth on Ethereum, January 2026; ultra.swap on EOS, May 2024)
• Telos (telos.evm, May 2024)
• Alcor (alcorstaking, April 2024)
• Redefind.io (multiple contracts, September 2024)
• Additional clients include Dfinity, Offchain, Thorchain, and others

As of 2026, Sentnl reports 500+ protected clients, $3bn+ in protected value, 0 contracts exploited post-audit, and 1,000+ vulnerabilities detected.

Why Choose Sentnl

Sentnl differentiates itself through deep human-led auditing complemented by automated tools, fast turnaround times, transparent communication, and a proven track record with zero post-audit exploits. The firm is known specifically for its advanced fuzzing techniques, highlighted by the CEO of the EOS Network Foundation as "industry-leading." Sentnl serves blockchain projects of all sizes seeking to secure smart contracts, protocols, and token economies before deployment.