First Up
Remote Sr. Software Engineer, Fullstack
Job Description
Salary: £60,000 - 100,000 per year
Requirements:- Bachelors degree in Computer Science or a related field, or equivalent experience.
- 5+ years of experience building reliable, performant applications and microservices in production environments.
- Strong full-stack fluency across frontend, backend, and database layers.
- Familiarity with Ruby on Rails, TypeScript, Node.js, or React.js is a strong plus.
- Technical depth in at least one area such as distributed systems, multi-tenant SaaS, application databases, networking, security, serverless, or event streaming.
- Strong communication skills and the ability to collaborate across teams.
- Curiosity, a learning mindset, and a desire to teach and support others.
- Build and own scalable SaaS applications end-to-end across frontend, backend, and data layers.
- Write production-grade code that is reliable, readable, efficient, and testable.
- Conduct thoughtful code reviews and create comprehensive documentation.
- Design future-ready architectures and proactively address gaps before they become problems.
- Drive system availability and performance by investigating and resolving reliability issues across the stack.
- Advocate for better performance and efficiency across software, systems, and processes.
- Champion a shift-left quality culture with unit, integration, and contract testing throughout the development lifecycle.
- Leverage and advocate for AI-assisted tools to accelerate development while maintaining engineering judgment and accountability.
- Drive team-wide best practices, mentor engineers, and raise overall engineering quality.
- Partner with Product and Design to translate requirements into intuitive user interfaces and make informed technical trade-offs.
- Champion engineering best practices across teams and help solve complex, high-impact problems.
- AI
- Backend
- Cloud
- Frontend
- Support
- Rails
- React
- Ruby
- Security
- Serverless
- TypeScript
- microservices
- NodeJS
- Copilot
- GitHub
- JavaScript
- TM1
- UX UI Design
- Fullstack
More:
We are Firstup, the communication pipeline for the worlds workforce, serving 40 of the Fortune 100 companies and reaching more than 17 million employees daily. Our mission is to improve the employee experience at every moment that matters and make work better for every worker. We are looking for a Senior Full Stack Engineer to help us deliver large-scale, multi-tenant cloud services with a strong focus on availability, fault tolerance, and elegant architecture. We offer an excellent PTO program, great health benefits, a casual and friendly environment, remote work, and a leadership team that supports personal and professional growth. We are an inclusive, high-growth company that values bold ideas, collaboration, and thriving in an environment of ambiguity.
last updated 40 week of 2026
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About First Up
First Up
Leicester
IT
Skills & Technologies
Inferred from job description
Salary Insight
£80,000
This role
£60,000
UK median
This salary is 33% above the UK median for Software Engineers (£60,000/yr).
Based on 2024–2025 UK technology sector benchmarks