Sr. Site Reliability Engineer (UK)

At Firstup, our mission is to improve the employee experience at every moment that matters, large and small. As the communication pipeline for the world's workforce, we now serve 40 of the Fortune 100 companies, reaching and connecting more than 17 million employees daily.

Our employees are experts in the employee experience, workforce communications and technology.

Joining Firstup means joining a movement to make work better for every worker. As the world’s first intelligent communication platform, Firstup meaningfully engages employees at every moment from hire to retire, and delivers engagement insights to help companies support, promote and retain their talent. Our movement has taken root and is evident in our world-class customer base. Now we need your help. Ready to make a difference in the world?

Job Summary

The Senior Site Reliability Engineer is responsible for improving the reliability, scalability, security, and operational efficiency of Firstup’s business-critical, multi-tenant cloud platform. This role leads complex incident response and root-cause improvements, balancing immediate customer and production needs with durable, scalable solutions. Working closely with Engineering, Information Security, and Customer Success, the Senior Site Reliability Engineer helps build an operability culture that protects customers, reduces risk, and supports the continued growth of the platform.

BS or MS in Computer Science (or equivalent diplomas and/or certifications) with 8+ years of relevant experience.

Strong experience in Site Reliability Engineering, production engineering, platform engineering or a comparable role supporting large-scale, distributed, customer-facing applications, ideally in a multi-tenant environment.

Demonstrated ability to troubleshoot across the full technology stack, including application code, APIs, containers, Kubernetes, cloud infrastructure, networking, databases and third-party dependencies.

Strong experience operating production workloads in AWS and Kubernetes-based environments.

Strong understanding of observability principles, with hands-on experience in monitoring, logging, distributed tracing, and APM. Deep practical expertise with Datadog is required.

Proven experience defining and implementing SLIs, SLOs, error budgets, reliability scorecards and operational health metrics.

Experience diagnosing application latency, resource contention, database performance, dependency failures and complex distributed-system behavior.

Strong automation and software-engineering skills using one or more languages such as Python, Go, Java, JavaScript/TypeScript or similar.

Experience with infrastructure as code, including Terraform, as well as CI/CD pipelines, configuration management, and automated deployment practices.

Strong ownership mindset with the ability to independently identify reliability gaps, prioritize improvements and drive initiatives through completion.

Excellent written and verbal communication skills, including the ability to explain complex production issues and reliability risks to both technical and non-technical stakeholders.

Willingness to participate in an on-call rotation and continuously improve the on-call experience through better tooling, documentation and automation.

Because you care - about people, the work you do, and the connections you make. Work is such a large part of life; it only makes sense to make it awesome.

If you want to engage brilliant minds in a high-growth and inclusive environment where ideas are rewarded regardless of who they come from, join us. This is a rapidly changing space so if you thrive on ambiguity, are hungry for a challenge, and have the guts to speak your mind, you could be a perfect fit.

We offer an excellent PTO program, great health benefits, a casual and friendly environment, remote work, and a leadership team who truly believes in your growth – both personally and professionally.

Firstup is committed to providing equal employment opportunities to all applicants for employment and to all employees, without regard to race, color, religion, gender, sexual orientation, gender identity or expression, national origin, age, protected disability, veteran status, or any other protected status in accordance with applicable federal, state or local laws.