Protocol Security Engineer

Matter Inc.; Portugal; Remote; EUR 125,000 - 178,000; Full time

Benefits offered by this job

Fully Remote

Occasional travel

Token incentives program

No geographic pay discounts

Job summary

Matter Labs is seeking a hands-on security engineer to protect ZK-based core components, review contracts, and drive threat modeling for the platform. You will own secure architecture decisions and collaborate across teams in a fast-paced, remote setting.

Applicants should have a strong background in security engineering, distributed systems, and proficiency in Solidity and Rust, with excellent English communication. This role is fully remote with travel for events as needed.

Qualifications

• Proven security engineering or security research background with verifiable results.
• Experience in threat modeling, security-focused code review, or vulnerability research on production systems.
• Strong ability to review code across languages (Solidity, Rust, C++, Go, Scala).
• Deep knowledge of algorithms and data structures with hands-on implementation.
• English fluency and clear written/spoken communication.

Responsibilities

• Threat-model and review Solidity contracts and protocol components.
• Own secure architecture and implementation decisions for critical systems.
• Track adversaries by following hacks and attack vectors; translate lessons into fixes.
• Scale secure design practices across development teams.
• Support incident response and security investigations under time pressure.

Skills

Security engineering

Threat modeling

Code review

Distributed systems

English proficiency

Tools

Rust

Solidity

C++

Go

Scala

Job description

About Matter Labs

Matter Labs builds private settlement infrastructure that lets regulated institutions settle directly with each other without exposing data, ceding control, or waiting days. Global finance moves $4 quadrillion a year on systems designed for paper and telex. The institutions that built them - from clearing houses to exchanges to the world's largest banks, institutions are now actively replacing them.

About Matter Labs

Matter Labs builds private settlement infrastructure that lets regulated institutions settle directly with each other without exposing data, ceding control, or waiting days. Global finance moves $4 quadrillion a year on systems designed for paper and telex. The institutions that built them - from clearing houses to exchanges to the world's largest banks, institutions are now actively replacing them. Our core product, Prividium, gives each institution its own private settlement environment (a Prividium Zone) with independent governance and built-in interoperability across counterparties, asset classes, and jurisdictions. Settlement happens through zero-knowledge proofs: one party proves a transaction is valid without revealing any underlying data to the counterparty. The only private settlement infrastructure built on zero-knowledge cryptography. Founded in 2018. Backed by a16z and Union Square Ventures. A fully remote team of around 70 with eight years of production zero-knowledge infrastructure behind us, now pointed at the biggest problem in institutional finance.

The role

You will protect ZKsync's core: smart contracts, ZK circuits, and blockchain nodes. Your reviews, threat models, and incident work decide whether vulnerabilities are found by us or by attackers. The role owns internal security reviews of critical components, threat modeling, adversary research, and the security side of incident response, and it carries broad license to spot gaps and fix them beyond any assigned list. It is a hands-on individual contributor role for someone who wants to know how things break and applies that instinct ethically where the stakes are high.

What you'll do

• Break things on purpose. Threat-model and review Solidity contracts, blockchain state transition functions in Rust, and other critical systems before an attacker gets the chance.
• Own protocol components. Take responsibility for the secure architecture and implementation of the components you adopt, from design review through production.
• Track the adversary. Follow hacks, exploits, and new attack vectors across the industry and convert the lessons into concrete improvements in our systems.
• Scale security through others. Embed secure-design practice across development teams and influence architecture decisions early, without formal authority.
• Use AI on defense. Apply modern AI systems to scale security work, while accounting for attackers using the same tools.
• Respond when it counts. Join security investigations and incident response, often under time pressure with incomplete information.

What we look for

• A record in security engineering or security research: threat modeling, security-focused code review, or vulnerability research on production systems, with findings you can walk through mechanism by mechanism.
• Proficiency in strongly typed languages such as C++, Go, or Scala. Rust and Solidity are our primary languages, and prior experience with them is not required.
• Deep grounding in algorithms and data structures, including their computational and memory complexity, with experience implementing them from scratch.
• Protocol-level debugging and root-cause analysis on complex distributed systems.
• Working knowledge of recent security incidents in the blockchain space and the prevention techniques behind them.
• Clear written and spoken English, the company's working language.

Nice to have

Hands-on experience with Solidity smart contracts, ZK circuits, or core blockchain protocols. Public security research, audit reports, bug-bounty results, or CTF history all count as evidence.

Work model & pay

• Competitive base salary. Matter Labs applies no geographic pay discounts.
• Performance-based variable compensation with a defined annual target is additional. The plan may pay in ZK tokens or cash. A long-term token incentive is also additional and is paid in ZK tokens, with new-hire grants vesting over four years and a one-year cliff.
• Fully Remote. Occasional travel to team gatherings and industry events.
• Freedom & ownership culture: no time tracking (where legally applicable), minimum bureaucracy-only results matter.