Senior Database Engineer
Capital on Tap12 hours ago
London, United KingdomSenior
Responsibilities
- Own query and index performance across the transactional SQL Server estate using execution plans, Query Store, wait statistics, and production telemetry.
- Investigate and implement horizontal scaling approaches including multi-cluster architecture, contained availability groups, sharding, partitioning, archival, denormalisation, caching, and read replicas.
- Improve latency-critical card authorization and ledger read/write paths against agreed p99 budgets.
- Own high availability and disaster recovery, including availability groups, failover, backup and restore testing, RTO/RPO targets, and operational runbooks.
- Build self-service tooling for query-plan regression detection and query-performance diagnostics.
- Automate database operations using PowerShell, Python, or Terraform and manage configuration as code.
- Manage SQL Server cost alongside latency and uptime metrics.
- Review database designs with Product Engineering and Data Analytics and improve organization-wide data-access practices.
- Lead and contribute to production incident response.
Requirements
- Substantial experience running Microsoft SQL Server in production at scale, including self-managed SQL Server, Managed Instances, or Azure SQL.
- Deep knowledge of the SQL Server query optimizer, plan cache, indexing, statistics, locking, blocking, isolation levels, tempdb, and wait types.
- A demonstrated record of specific, measurable database performance improvements.
- Experience scaling relational data beyond query tuning alone.
- Expert-level T-SQL skills and comfort writing application code, plus PowerShell or Python and infrastructure as code.
- Hands-on experience designing high availability and disaster recovery systems and leading production incidents.
- Experience working with ORMs, ideally Entity Framework, and understanding their performance tradeoffs.
- Working knowledge of other database engines such as PostgreSQL and their relative advantages and disadvantages.
- Ability to explain technical concepts and tradeoffs to non-database specialists.
Benefits
- London, Old Street location with two days in the office each week.
- Private healthcare including dental and optician services through Vitality.
- Worldwide travel insurance through Vitality.
- Anniversary rewards, including £250, £500, £750, and a four-week fully paid sabbatical.
- Salary sacrifice pension scheme with up to 7% matching.
- 28 days of holiday plus bank holidays.
- Annual learning and wellbeing budget.
- Enhanced parental leave.
- Cycle to Work Scheme.
- Season Ticket Loan.
- Six free therapy sessions per year.
- Dog-friendly offices with free drinks and snacks, a pool table, arcade machine, beer tap, and office dogs.
Tech Stack
Categories
About Capital on Tap
Capital on Tap provides an all-in-one business credit card and expense management platform for small businesses, offering funding, employee card controls, and cashback rewards. It earns revenue through card usage and lending, and serves companies in the UK and US via a self-serve online application with instant decisions. Founded in 2012 and headquartered in London, it reports more than 200,000 small business customers and over £20 billion in card spend.