Software Engineer - SMS International
KlaviyoLondon, UKPosted 19 March 2026
Tech Stack
Job Description
At Klaviyo, we value the unique backgrounds, experiences and perspectives each Klaviyo (we call ourselves Klaviyos) brings to our workplace each and every day. We believe everyone deserves a fair shot at success and appreciate the experiences each person brings beyond the traditional job requirements. If you’re a close but not exact match with the description, we hope you’ll still consider applying. Want to learn more about life at Klaviyo? Visit klaviyo.com/careers to see how we empower creators to own their own destiny.
Why you should join the SMS International team that is part of Mobile Platforms
The Mobile Platforms team at Klaviyo is responsible for empowering the over 150,000 Ecommerce clients we work with on a global scale to deliver effective experiences on mobile devices. This team focuses on performance optimization and continuous development of our Mobile Marketing Channels (SMS, Push Notifications, In App Messages, WhatsApp and RCS), Mobile SDKs (iOS, Android and React Native). While Email was how Klaviyo began, Mobile messaging is truly the way of the future.
The SMS International team within Mobile Platforms is responsible for the expansion of SMS capabilities into new countries and regions and is also spearheading the development of RCS as a new capability to be offered to customers alongside existing channels. We have an ambitious roadmap for 2026 that puts the team at the heart of the company’s objectives and it is an exciting time to join the team!
About the Role
As a Fullstack Software Engineer II joining the SMS International team you will be working with a team of 5 other colleagues to deliver RCS and SMS International expansion to meet the company’s objectives. You will get the chance to build brand new services, understand how they fit into the bigger picture and plan how to architect and scale them successfully to serve our customers.
Technologies we use (not exhaustive):
Python, Django, Go, React, SQS, Celery, MySQL, DynamoDB, Elasticache, Redis
Amazon Web Services (EC2, RDS, Aurora, etc.), Terraform, Kubernetes, Splunk, Buildkite, Grafana, Chronosphere and other modern DevOps tools
What we are looking for
3-5 years of experience in a software engineering discipline
Experience with full stack application development
Experience working with both monolithic and microservices architectures
Experience with database design that can withstand high query volumes
Experience with CI/CD pipelines
Experience debugging performance issues and improving application performance
An interest and aptitude for collaboration across teams and disciplines
Nice to Have
Experience creating new services with scalability in mind. Exposure to large-scale system design
Experience with AWS or any similar cloud provider
Communication domain experience
Our salary range reflects the cost of labour in the country where the job post is advertised. The base salary offered for this position is determined by several factors, including the applicant’s job-related skills, relevant experience, education or training, and work location.
In addition to base salary, our total compensation package may include participation in the company’s annual cash bonus plan, variable compensation (OTE) for sales and customer success roles, equity, sign-on payments, and a comprehensive range of health, welfare, and wellbeing benefits based on eligibility.
Your recruiter can provide more details about the specific salary/OTE range for your preferred location during the hiring process.
Base Pay Range in Local Currency:
£68,000
£102,000 GBP
Get to Know Klaviyo
We’re Klaviyo (pronounced clay-vee-oh). We empower creators to own their destiny by making first-party data accessible and actionable like never before. We see limitless potential for the technology we’re developing to nurture personalized experiences in ecommerce and beyond. To reach our goals, we need our own crew of remarkable creators—ambitious and collaborative teammates ... (truncated, view full listing at source)
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