Cloud Infrastructure Engineer (Open LMS) UK, Remote

Role DescriptionWe are looking for a Senior Cloud Infrastructure Engineer to join our team and help build, scale, and evolve our multi-tenant SaaS hosting platform on AWS. Our platform dynamically provisions, manages, and scales hundreds of Moodle LMS instances for education clients — powered by custom orchestration tooling, distributed service discovery, and infrastructure as code.This is a hands-on infrastructure role. You'll work across the full stack — from Terraform modules and Puppet manifests to Python automation and observability pipelines. The platform is not containerised — there is no Kubernetes here — so we're looking for someone who understands Linux systems deeply and can reason about distributed systems problems from first principles.You'll have real ownership and influence over the platform's architecture and direction as we continue to grow and evolve the infrastructure.What You'll Be DoingDesigning, building, and maintaining AWS infrastructure using Terraform (EC2, RDS, S3, SQS, Lambda, ALB, ElastiCache, Route 53, VPC networking)Writing and maintaining Puppet modules to configure and manage fleets of EC2 instances across multiple auto-scaling groupsMaintaining and extending Python-based automation and tooling that supports platform operationsOperating and improving distributed service discovery and configuration management (etcd)Managing and tuning a multi-tier caching strategy (Varnish, Redis/Valkey, PHP OPcache)Running and scaling our observability stack (Prometheus, Grafana, Loki, Fluentd, PagerDuty) and participating in on-call rotationsEvaluating and implementing distributed storage solutions as the platform evolvesImproving deployment workflows and release processesCollaborating with internal teams on API contracts, integration patterns, and operational toolingParticipating in incident response, root cause analysis, and platform reliability improvementsSkills and AptitudesStrong experience with AWS services in production — particularly EC2, RDS, S3, SQS, Lambda, ALB, ElastiCache, Route 53, IAM, and VPC networkingProficiency in authoring and maintaining Terraform modules for production infrastructureProficiency in authoring and maintaining Puppet modules (or equivalent agent-based configuration management) for fleet managementSolid Python skills — you'll be writing and maintaining production daemons, not just scriptsDeep Linux systems knowledge (Ubuntu) — comfortable with Apache/Nginx, PHP-FPM, Varnish, systemd, filesystem mounts, and networking fundamentalsUnderstanding of distributed systems concepts: consensus, leader election, distributed locking, eventual consistency, and the tradeoffs involvedProficiency in building and maintaining observability pipelines (Prometheus, Grafana, Loki, or equivalent) in productionComfortable working in a GitLab-based CI/CD workflowClear communicator who can document architectural decisions and explain technical tradeoffs to both technical and non-technical stakeholdersAdditionally, a Top Candidate Will Exhibit One or More of the Following Preferred QualificationsHands-on experience with distributed storage systems such as Ceph, GlusterFS, JuiceFS, CubeFS, or AWS EFS — particularly in the context of migration or evaluationFamiliarity with etcd (or similar distributed key-value stores like Consul or ZooKeeper) including watch APIs, TTL-based locking, and cluster operationsExperience with Varnish and VCL, especially dynamic backend routing or multi-tenant configurationsWorking knowledge of PHP — not to build applications, but to understand and maintain integration scripts that bridge infrastructure and application layersBackground in multi-tenant SaaS platform design — particularly database-per-tenant models on shared infrastructureFamiliarity with Moodle LMS or education technology platformsExperience with secrets management solutions (AWS Secrets Manager, HashiCorp Vault, Parameter Store) and automated credential rotationExperience designing zero-downtime deployment strategies for VM-based (non-containerized) environmentsOpen LMS is an equal employment opportunity/affirmative action employer and considers qualified applicants for employment without regard to race, gender, age, color, religion, national origin, marital status, disability, sexual orientation, or any other protected factor.Full-Time