Senior Software Engineer (Database Reliability)

Description

The company is a financial platform for small businesses, offering a business credit card, a spend management platform for SMEs, a savings product that reached £1 billion in funds within its first year, and a growing set of tools and financial products for running a small business.

The company has over 1,000 employees, £20bn in annual card spend, more than 200,000 customers and over 17,000 Trustpilot reviews averaging 4.7 stars, and it is profitable.

This is a hybrid role. The Database team works from the Moorgate (London) office 2 days per week.

Responsibilities

• Own performance across the transactional SQL Server estate, using execution plans, Query Store, wait statistics, production telemetry and other data-driven measures.
• Build and improve self-service tooling that lets development teams spot query plan regressions and diagnose their own query performance.
• Research, demo and promote advanced database technologies such as graph databases, vector stores and zero-downtime migrations to software engineers, showing how to use them with Entity Framework or other ORMs.
• Investigate and implement scaling approaches such as multi-cluster architecture, contained availability groups and sharding, so the distributed estate keeps up with customer growth and a rising number of services.
• Work with Product Engineering and the data analytics team, reviewing designs before release and raising how the wider engineering organisation handles data access.
• The platform runs on.NET and SQL Server on Azure and has outgrown its original design. This is the first dedicated Database Software Engineer role, focused on performance and scale and on giving engineers the tools and judgement to write data access that holds up in production.
• You will join a small, agile team of Database Engineers and SREs as a senior hands-on individual contributor. There is no ticket queue: you choose work that improves latency, cost and reliability, and you are expected to flag where re-architecture is needed.

Requirements

• Experience working with ORMs, ideally Entity Framework, and understanding of their performance trade-offs.
• Substantial experience running Microsoft SQL Server in production at scale, self-managed, on Managed Instances or on Azure SQL, where downtime and latency have direct commercial impact.
• Deep knowledge of SQL Server internals: the query optimiser and plan cache, indexing and statistics, locking, blocking and isolation levels, tempdb, and the wait types that reveal the real bottleneck.
• A record of specific, measurable performance improvements that you can explain from start to finish.
• Experience scaling relational data beyond what tuning alone can achieve, through partitioning, archiving, denormalisation, caching, read replicas or a deliberate move to another data store.
• Expert T-SQL, plus PowerShell and infrastructure as code. You write application code, not only scripts.
• Hands-on experience with HA/DR design and leading production incident response.
• Ability to explain technical concepts and trade-offs to people without a database background.
• Interview process: a 30-minute screening with a Talent Partner, a 60-minute technical chat with the Hiring Manager, a 90-minute technical interview with two team members, and a 30-minute values interview with the Head of Platform Engineering.

Conditions

Hybrid working, with the Database team in the Moorgate (London) office 2 days per week.

28 days of holiday plus bank holidays.

Equal opportunity statement is not included in this posting.

Benefits

• Octopus EV salary sacrifice scheme.
• Annual learning and wellbeing budget.
• Enhanced parental leave.
• Cycle to Work scheme.
• Season ticket loan.
• 6 free therapy sessions per year.
• Dog-friendly offices.
• Free drinks and snacks in the offices.