Firstup
Product Engineering
Sr.SoftwareEngineer,Fullstack(UK)
Neural analysis suggests this role is
optimal for Senior candidates.
“Sr. Software Engineer, Fullstack (UK) at Firstup. Skills: Public-facing APIs, Agentic tools, Third-party integrations, Shared platform services, Scalable solutions, Microservices, Cloud-native patterns, Generative AI tools, Coding agents. Design, build, and maintain public-facing APIs and Agentic tools. Develop and own integrations with external enterprise systems”
What You'll Achieve.
Improve the employee experience; Meaningfully engages employees at every moment; Delivers engagement insights; Accelerate delivery; Improve code quality
Industry & Context.
Help others solve complex problems; Identify, analyse, and resolve system availability, reliability, and performance issues
On-call rotations, Incident response, You build it, you run it environment
What They're Looking For.
Must Have
5+ years building reliable, performant applications and microservices, Proficiency in TypeScript and Node.js, Proven full-stack experience across frontend (React.js), backend, and database layers, Technical depth in at least one specialisation: networking, security, serverless, event streams, or similar, AWS experience, including compute, storage, networking, and monitoring, Excitement to build beautiful, intuitive products with a customer focus, Innate curiosity and a desire to learn and teach
Nice to Have
Ruby experience is a plus, Experience building and maintaining integrations with HRIS platforms such as Workday, SAP SuccessFactors, Dayforce, or similar enterprise HR systems, Experience with Kubernetes, Docker, and Helm, Experience with Datadog or similar observability and monitoring platforms, Demonstrated use of Generative AI tools or coding agents in development workflows, Experience in enterprise SaaS organisations, particularly HR Tech or regulated domains, Familiarity with ML/AI integration in production systems, Open-source contributions or a history of side projects
What You'll Do.
and maintain public-facing APIs and Agentic tools
Develop and own integrations with external enterprise systems
Build and maintain shared platform services
Write high-quality code
in-depth knowledge to develop and maintain large-scale multi-tenant services in the cloud
Actively use Generative AI tools and coding agents
Own production health for your services
Contribute to on-call rotations
and post-incident reviews
and resolve system availability
and performance issues
Translate business requirements into scalable technical solutions
How You'll Work.
Team & Collaboration
Collaborate across teams on industry standards and best practices; Partner with Product Management and Design
Full Job Description
## Description Who We Are At Firstup, our mission is to improve the employee experience at every moment that matters, large and small. As the communication pipeline for the world's workforce, we now serve 40 of the Fortune 100 companies, reaching and connecting more than 17 million employees daily. Our employees are experts in the employee experience, workforce communications and technology. Joining Firstup means joining a movement to make work better for every worker. As the world’s first intelligent communication platform, Firstup meaningfully engages employees at every moment from hire to retire, and delivers engagement insights to help companies support, promote and retain their talent. Our movement has taken root and is evident in our world-class customer base. Now we need your help. Ready to make a difference in the world? Job Summary The Sr. Software Engineer will join the team responsible for Firstup's public APIs, Agentic tools, third-party integrations with enterprise systems such as HRIS platforms, and shared platform services. You will deliver innovative, scalable solutions while constantly improving our approach to architecture, scale, availability, and fault-tolerance. You are an active user of Generative AI tools and coding agents, applying them daily to accelerate delivery and improve code quality. ## Responsibilities 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
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