Blockchain is connecting the world to the future of finance. As the most trusted and fastest-growing global crypto company, it helps millions of people worldwide safely access cryptocurrency. Since its inception in 2011, Blockchain has earned the trust of over 90 million wallet holders and more than 40 million verified users, facilitating over $1 trillion in crypto transactions. We are looking for a Senior Security Engineer, Infrastructure & Reliability to lead by example and drive technical discussions across engineering teams. In this hands-on hybrid role, you will build scalable security guardrails and automation across cloud, CI/CD, and developer platforms—combining SRE and security disciplines to protect our global stack and support proactive threat defense. Our day-to-day work is interesting and dynamic, driven by a focus on proactive threat actor identification and in-depth investigation of security issues. These practices are key to ensuring strong product security and fostering continuous, iterative improvement. Responsibilities Design, implement, and automate security controls across GCP and our wider infrastructure, focusing on least-privilege access and leveraging Terraform, policy-as-code, and CI/CD pipelines to prevent misconfigurations, detect configuration drift, and continuously enforce security baselines. Partner closely with SRE teams to establish cloud-native deployment workflows, enforcing explicit CI/CD gates, approval flows, artifact provenance, and build security. Partner with SRE to harden and manage the security posture of global networking infrastructure, corporate VPN, and perimeter tooling (e.g., Cloudflare) to prevent unauthorized exposure. Design and deploy internal tooling to support the SOC and Security Engineering teams. Conduct threat modeling, design reviews, and architectural assessments for new and existing systems. Maintain internal security documentation, standard operating procedures, and developer best-practice guidance. Provide specialized infrastructure, cloud, automation, and CI/CD support during incident response operations and threat investigations. Requirements 4+ years of experience in Security Engineering, Platform Security or SRE/DevOps, with demonstrated ownership of security controls in production environments. Ability to assess infrastructure security risks, conduct threat modeling and security design reviews, and translate findings into practical, scalable engineering controls. Hands-on experience implementing security controls and automation in cloud environments (GCP preferred). Experience designing secure CI systems and workflows, dealing with artifact provenance, approval flows, and code protection (GitHub Actions preferred). Solid understanding of network-level security protocol concepts and mitigations (TLS, HTTPS, network segmentation). Proficiency in Infrastructure as Code (Terraform) and modern scripting/automation languages (Python, Bash, or Go). Strong analytical and problem-solving skills, with a bias toward automation over manual workflows and clear cross-team communication. Familiarity with perimeter and monitoring tooling (e.g., Cloudflare/WAF, SIEM, Wazuh/HIDS, EDR, and incident-management platforms). Nice to have Knowledge of security standards and governance frameworks (e.g., CIS Benchmarks, NIST, SOC2, ISO 27001, PCI DSS) and how to operationalize them. Hands-on experience building and maintaining a SIEM comprised of open-source and hosted components. Experience securing consumer-facing web and iOS/Android applications. Experience designing secrets policies and administering Vault or other HashiCorp products. Proven track record of managing security vendor relationships and technical deliverables. Hands-on experience administering secrets management platforms (e.g., HashiCorp Vault), including secret rotation and lifecycle automation. Compensation & Perks Full-time salary based on experience and meaningful equity in an industry-leading company This is a role based in our London office, with a mandatory in-office presence four days per week. Work from Anywhere Policy: You can work remotely from anywhere in the world for up to 20 days per year. ClassPass Unlimited vacation policy; work hard and take time when you need it Apple equipment The opportunity to be a key player and build your career at a rapidly expanding, global technology company in an emerging field Flexible work culture Blockchain is committed to diversity and inclusion in the workplace and is proud to be an equal opportunity employer. We prohibit discrimination and harassment of any kind based on race, religion, color, national origin, gender, gender expression, sex, sexual orientation, age, marital status, veteran status, disability status or any other characteristic protected by law. This policy applies to all employment practices within our organization, including hiring, recruiting, promotion, termination, layoff, recall, leave of absence, and apprenticeship. Blockchain makes hiring decisions based solely on qualifications, merit, and business needs at the time. The personal data you provide will be used by Blockchain to process your application. To learn more about your rights, see our Applicant Privacy notice.
