Senior Security Engineer — Blockchain & Open Finance

The Bitcoin Street Journal; Polska; Hybrid; PLN 466,000 - 700,000; Full time

Job summary

Payward in SF- or global-hub operations seeks a security-focused engineer who can own security deliverables end to end. You will coordinate audits, respond to due-diligence requests, and harden cryptographic and signing workflows across multiple chains.

Your background includes TypeScript/Node.js, offensive security, and strong risk judgment. You will work with the Payward security, CISO, and compliance teams, review critical code paths, and contribute to platform improvements while responding

Qualifications

• Engineer first with production code experience in TS/Node.js.
• Strong fundamentals in security, authn/authz, and cryptography.
• Offensive security experience in pentesting or red-team activities.

Responsibilities

• Coordinate and review smart-contract audits and security questionnaires.
• Pentest web apps, APIs, backends, and on-chain components regularly.
• Threat-model systems and maintain a living risk view with mitigations.
• Review code for auth, crypto, custody, signing, and fund movement.
• Harden platform with secrets handling, IAM, and supply-chain hygiene.
• Support incidents with detection, triage, and post-mortems.
• Contribute to product engineering with TypeScript backlog work.

Skills

TypeScript

Node.js

Security auditing

Pentesting

Cryptography

Threat modeling

Tools

OWASP

HSM

MPC

Smart contracts

Job description

Payward in SF- or global-hub operations seeks a security-focused engineer who can own security deliverables end to end. You will coordinate audits, respond to due-diligence requests, and harden cryptographic and signing workflows across multiple chains.

Your background includes TypeScript/Node.js, offensive security, and strong risk judgment. You will work with the Payward security, CISO, and compliance teams, review critical code paths, and contribute to platform improvements while responding