Senior Software Engineer, Distributed Systems - Messaging

5+ years of professional software engineering experience building and operating online, real-time distributed systems where latency, throughput and reliable processing matter to customers or downstream services.

designing and building event-driven or asynchronous systems, using events, queues, streams or messaging platforms as a core part of the architecture.

with streaming or message-queue platforms such as Kafka, Pulsar, RabbitMQ, SQS, or similar, and an understanding of the tradeoffs they introduce around throughput, latency, ordering, retries and reliability.

with large-scale system architecture, technologies and patterns.

Have a good understanding of their pros/cons and use scenarios, able to apply them to system design by making appropriate tradeoffs to meet business needs.

Deep fluency in at least one backend language (Python, Go, Java, Scala, or similar) and comfort navigating large, complex codebases.

Love digging into performance and scalability issues to drive breakthrough solutions -- whether it's a performance degradation, a database query timing out, or a queue that just won’t drain.

You recognize all problems can be solved.

Passionate about growing and improving a product daily using a data driven mindset, familiar with system monitoring and alerting techniques.

Proven experience with being a coach and a mentor for team members and helping them grow.

Solid understanding of distributed systems fundamentals: consistency models, CAP, tradeoffs, idempotency, retries and backoff, rate limiting, and graceful degradation.

Ability to operate effectively in a high-ownership culture: you drive your work forward, unblock yourself, and hold yourself accountable to outcomes, not just effort.

Technologies we use (not exhaustive):

Data & Infrastructure: MySQL, Redis, Memcached, Apache Zookeeper, Apache Pulsar

Cloud & DevOps: AWS (EC2, RDS, Aurora), Terraform, Jenkins

This role is based in Dublin, Ireland and follows a hybrid working model.

Klaviyo supports work authorization and relocation for this position.

At Klaviyo, we enjoy tackling meaningful engineering challenges and value people who take ownership, learn continuously, and collaborate openly.

We are committed to building inclusive teams and encourage applications from all backgrounds.

Klaviyo is growing fast and we have openings for all skill levels across all of our teams.

Learn more about our engineering culture at https://klaviyo.tech

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.

This role may require up to 10% travel for purposes such as new hire onboarding, client or partner work if applicable, team meetings, and industry events.

Travel is coordinated in advance.

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 who stay focused on our north star: delighting our customers.

If you’re ready to do the best work of your career, where you’ll be welcomed as your whole self from day one and supported with generous benefits, we hope you’ll join us.

AI fluency at Klaviyo includes responsible use of AI (including privacy, security, bias awareness, and human-in-the-loop).

We provide accommodations as needed.

By participating in Klaviyo’s interview process, you acknowledge that you have read, understood, and will adhere to our Guidelines for using AI in the Klaviyo interview Process.

For more information about how we process your personal data, see our Job Applicant Privacy Notice.

Klaviyo is committed to a policy of equal opportunity and non-discrimination. We do not discriminate on the basis of race, ethnicity, citizenship, national origin, color, religion or religious creed, age, sex (including pregnancy), gender identity, sexual orientation, physical or mental disability, veteran or active military status, marital status, criminal record, genetics, retaliation, sexual harassment or any other characteristic protected by applicable law.