apeirum

• Administer and harden self-hosted Linux servers • Design, set up and operate self-managed, multi-node Kubernetes clusters (lifecycle, upgrades, networking, storage, ingress, RBAC, high availability) • Manage the Docker / container lifecycle across environments • Build and maintain Infrastructure-as-Code and configuration management (Helm, Kustomize, Ansible) • Own CI/CD pipelines with integrated security scanning (GitLab CI/CD) • Run the monitoring, logging and observability stack (Elastic) • Design and operate encrypted backups: retention, rollover and restore validation • Deliver controlled, repeatable system updates and upgrades • Automate and script infrastructure (Bash) • Lead incident response and keep operational documentation current • Manage DNS and domains

Role Description At apeirum, we embed senior engineers into growing European companies — no juniors dressed up as seniors, no agency layers, full accountability from day one. We're now looking for a DevSecOps / Infrastructure Engineer who runs self-hosted, security-first infrastructure end to end: from hardening a Linux server to operating multi-node Kubernetes in production, to keeping an ISO 27001 ISMS audit-ready. This is a hands-on role for someone equally comfortable debugging a failing cluster upgrade in the morning and writing the change-management evidence an auditor reads three months later. If you like owning infrastructure rather than just consuming a managed cloud, you'll fit right in. The setup depends on where you're based: a permanent employment contract for candidates based in Spain, or a freelance/contract engagement for candidates based in Portugal. Fully remote within Spain and Portugal, on CET working hours. Tasks - Infrastructure & DevSecOps (core focus): - Administer and harden self-hosted Linux servers - Design, set up and operate self-managed, multi-node Kubernetes clusters (lifecycle, upgrades, networking, storage, ingress, RBAC, high availability) - Manage the Docker / container lifecycle across environments - Build and maintain Infrastructure-as-Code and configuration management (Helm, Kustomize, Ansible) - Own CI/CD pipelines with integrated security scanning (GitLab CI/CD) - Run the monitoring, logging and observability stack (Elastic) - Design and operate encrypted backups: retention, rollover and restore validation - Deliver controlled, repeatable system updates and upgrades - Automate and script infrastructure (Bash) - Lead incident response and keep operational documentation current - Manage DNS and domains - Microsoft 365 administration: - Administer and secure the tenant: Exchange Online, SharePoint Online, Teams - Own identity and access management (Entra ID), MFA and conditional access - ISO/IEC 27001 / ISMS support: - Maintain and improve ISMS documentation and policies - Operate and evidence ISO 27001 controls (access management, logging, change management) - Run risk assessments and track mitigations - Prepare for and support internal and external / surveillance audits Qualifications - 5+ years of hands-on infrastructure / DevSecOps experience in production, self-hosted environments (not purely managed cloud) - Deep, operational Kubernetes knowledge — you've run clusters, not just deployed to them - Strong Linux administration and hardening background - Solid command of IaC and configuration management (Helm, Kustomize, Ansible) and CI/CD (GitLab) - Experience with observability (Elastic or comparable) and robust backup/restore practices - Working knowledge of Microsoft 365 / Entra ID administration and security - Practical familiarity with ISO 27001 / ISMS — controls, evidence and audits, not just theory - A security-first mindset, strong documentation habits, and the discipline to keep changes controlled and repeatable - Fluent English; German is a plus - Based in Spain or Portugal, able to work CET hours Benefits - Remote-first across Spain and Portugal, on CET — real collaboration, not async lag - Senior-only culture — work alongside experienced engineers, no juniors to manage - AI-leveraged engineering — modern AI tooling so one senior does the work of several - Flexible engagement — permanent employment (Spain) or freelance/contract (Spain or Portugal), your call - End-to-end ownership of the stack, with the autonomy that comes with it - Variety across infrastructure, cloud security and compliance work for interesting European clients