Sr. Software Engineer, Fullstack (UK)

Design, build, and maintain public-facing APIs and Agentic tools that enable enterprise customers to integrate with and extend the Firstup platform.

Develop and own integrations with external enterprise systems, including HRIS platforms such as Workday, SAP SuccessFactors, and Dayforce.

Build and maintain shared platform services used across the wider engineering organisation.

Write high-quality code (reliable, readable, efficient, testable, scalable, maintainable), provide thorough code reviews, and create comprehensive tests and documentation.

Apply broad, in-depth knowledge to develop and maintain large-scale multi-tenant services in the cloud.

Actively use Generative AI tools and coding agents in day-to-day workflows to improve code quality and accelerate delivery.

Collaborate across teams on industry standards and best practices to help others solve complex problems.

Design future-ready solutions and address architectural gaps using modern microservices and cloud-native patterns.

Own production health for your services, contributing to on-call rotations, incident response, and post-incident reviews in a "you build it, you run it" environment.

Identify, analyse, and resolve system availability, reliability, and performance issues, contributing to observability and resiliency improvements.

Partner with Product Management and Design to translate business requirements into scalable technical solutions.