Senior Security Engineer (Freelance) — AWS & Kubernetes Infrastructure | Fast-Scaling SaaS - Barcelona We're looking for a Senior Security Engineer to join a fast-scaling SaaS company (10M+ end users) as a freelancer, via Shakers.

You'll be the driving force behind building security from the ground up — hardening AWS and Kubernetes infrastructure, leading incident response, and establishing a foundational security program that unblocks enterprise sales. What you'll do:

Harden AWS, Kubernetes clusters, and application security end-to-end

Implement and integrate SAST/DAST scanning and dependency checks into engineering sprints

Strengthen identity management (SSO, MFA, Google Workspace security)

Build a vulnerability management program with alerting and remediation workflows

Lead incident response, write runbooks, and support enterprise security questionnaires

Design security training, phishing simulations, and a security champions network





Define pragmatic security policy and governance for secure-by-design scaling What we're looking for:

5+ years in security engineering, infrastructure security, or security software engineering, including building a security program from scratch in a startup/scale-up

Strong hands-on AWS security (IAM, Security Groups, WAF)

Kubernetes, container security, and IaC security (Terraform, Helm)

Solid grasp of OWASP Top 10, secure coding, API security

Experience with SAST/DAST tooling and dependency scanning

Programming proficiency in Python, TypeScript, or Golang

Nice to have: GDPR/SOC2/ISO27001 exposure, pentesting background, Django/React/PostgreSQL familiarity Hybrid from Barcelona one day per week This is a freelance opportunity through Shakers, the platform connecting top independent tech talent with growth companies across Europe.

📌 Senior Security Engineer - BCN (Barcelona)
🏢 Shakers
📍 Barcelona