Cloud Infrastructure Engineer (Open LMS) UK, Remote

Role Description

We 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 Doing

• Designing, 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 groups
• Maintaining and extending Python-based automation and tooling that supports platform operations
• Operating 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 rotations
• Evaluating and implementing distributed storage solutions as the platform evolves
• Improving deployment workflows and release processes
• Collaborating with internal teams on API contracts, integration patterns, and operational tooling
• Participating in incident response, root cause analysis, and platform reliability improvements

Skills and Aptitudes

Strong experience with AWS services in production — particularly EC2, RDS, S3, SQS, Lambda, ALB, ElastiCache, Route 53, IAM, and VPC networking

Proficiency in authoring and maintaining Terraform modules for production infrastructure

Proficiency in authoring and maintaining Puppet modules (or equivalent agent-based configuration management) for fleet management

Solid Python skills — you'll be writing and maintaining production daemons, not just scripts

Deep Linux systems knowledge (Ubuntu) — comfortable with Apache/Nginx, PHP-FPM, Varnish, systemd, filesystem mounts, and networking fundamentals

Understanding of distributed systems concepts: consensus, leader election, distributed locking, eventual consistency, and the tradeoffs involved

Proficiency in building and maintaining observability pipelines (Prometheus, Grafana, Loki, or equivalent) in production

Comfortable working in a GitLab-based CI/CD workflow

Clear communicator who can document architectural decisions and explain technical tradeoffs to both technical and non-technical stakeholders

Additionally, a Top Candidate Will Exhibit One or More of the Following Preferred Qualifications

Hands-on experience with distributed storage systems such as Ceph, GlusterFS, JuiceFS, CubeFS, or AWS EFS — particularly in the context of migration or evaluation

Familiarity with etcd (or similar distributed key-value stores like Consul or ZooKeeper) including watch APIs, TTL-based locking, and cluster operations

Experience with Varnish and VCL, especially dynamic backend routing or multi-tenant configurations

Working knowledge of PHP — not to build applications, but to understand and maintain integration scripts that bridge infrastructure and application layers

Background in multi-tenant SaaS platform design — particularly database-per-tenant models on shared infrastructure

Familiarity with Moodle LMS or education technology platforms

Experience with secrets management solutions (AWS Secrets Manager, HashiCorp Vault, Parameter Store) and automated credential rotation

Experience designing zero-downtime deployment strategies for VM-based (non-containerized) environments

Open 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.