Hybrid Senior Software Engineer

at Sequence

• Job title: Senior Software Engineer
• Job type: Full Time
• Experience level: Senior
• Salary: £90,000 - £110,000 per year
• Degree requirement: Bachelor's Degree
• Tech skills: Cloud, Kotlin
• Location requirements: Hybrid, London, United Kingdom

About the role

• Senior Software Engineer building revenue-critical infrastructure for B2B companies at Sequence. Join a collaborative team shaping the future of billing solutions.

Responsibilities

• Own revenue-critical event infrastructure. You'll work on systems that process customer usage data on which billing and invoicing depend. Design event streaming pipelines that handle high throughput with low latency. Build robust systems where data accuracy is non-negotiable and uptime is measured in nines.
• Design scalable data systems. You'll work with event streaming architectures, building sophisticated ingestion pipelines and query optimization strategies.
• Shape our backend architecture. You'll tackle our most complex technical challenges and set the standards for how we solve them.
• Build for the next phase of growth. You'll design systems that work beautifully today and scale to 10x the load tomorrow.
• Drive impact on a small team. You'll have significant influence on what we build, how we build it, and how we work together.

Requirements

• Love building systems that scale. You've worked on backends that handle significant load and understand the tradeoffs in designing for throughput, latency, and cost.
• Have strong experience in event-driven architectures. You've built pub/sub systems, worked with event streaming platforms, and understand the nuances of event delivery semantics, backpressure, and ordering guarantees.
• Think deeply about data systems. You've worked with analytical databases or OLAP systems. You can reason about columnar storage, indexing strategies, and query optimization without needing a whiteboard.
• Own your infrastructure. You've provisioned cloud resources, written infrastructure-as-code, and made architectural decisions that balance competing constraints.
• Write backend code in strongly-typed languages. Our services run on Kotlin, though you don't need prior experience - many of our engineers learned it here and loved the challenge.
• Care about customers and their problems. You'll work directly with customer data and build systems that power their revenue.
• Thrive in uncertainty. We're an early-stage company. Priorities shift as we learn from customers.

Benefits

• Early ownership of critical infrastructure at a fast-growing company
• Real architectural influence - your decisions will shape how we build for years
• A collaborative team that values deep technical work and continuous learning
• We support remote work within +/- 3 hours of GMT and EST, or you can work from our offices in central London or New York - whatever you prefer.