Senior Full-Stack Engineer in London

We are looking for a Senior Full-Stack Engineer who thrives at the intersection of product, infrastructure, and AI-driven development. In this role, you will architect and build scalable web applications while helping shape the technical foundation of Bluefish’s AI marketing platform. You’ll work closely with AI engineers, product managers, and designers to deliver impactful features, ensuring solutions are both technically sound and aligned with customer needs. We’re looking for someone with a strong product mindset who cares deeply about user outcomes, not just implementation. As a collaborative team player, you will contribute to a culture of ownership, high engineering standards, and continuous improvement, mentoring teammates, participating in thoughtful design discussions, and helping the team move quickly while maintaining quality. This role offers the opportunity to own critical systems, influence technical direction, and help define how AI-assisted development powers the next generation of marketing technology. The role is linked with our office in London, but we offer remote work in the UK.

What You’ll Be Doing:

• Architect, develop and own the implementation of scalable, secure web applications, making deliberate tradeoffs between speed, reliability, and complexity.
• Bridge design and engineering, validating technical feasibility of UI/UX designs and driving performance optimization from first render to database query.
• Set and enforce a high engineering bar through rigorous code reviews, coding standards, and spec-driven development (SDD) practices that keep the team aligned and moving fast.
• Lead system scaling initiatives to support 100x current load, identifying bottlenecks, redesigning critical paths, and hardening infrastructure before they become incidents.
• Work shoulder-to-shoulder with AI engineers, product managers, and designers to shape solutions that are technically sound and impactful.
• Stay ahead of shifts in GenAI, LLMs, GEO, and AI-driven marketing, translating emerging trends into concrete product and technical bets.

Qualifications:

• 5+ years of full-stack experience with TypeScript and React, shipping production-grade applications end to end.
• Experience or willingness to code with Python is also required.
• Fluent in AI-assisted development, leveraging LLM tooling to accelerate delivery without compromising code quality or architectural integrity.
• Design, deploy, and operate AWS infrastructure using Terraform, with strong emphasis on security, cost-efficiency, and operational reliability.
• Build high-throughput, fault-tolerant APIs with deep expertise in query optimization, indexing strategies, and data access patterns at scale.
• Strong system design and data modeling fundamentals, with a track record of architecting solutions that hold up under real-world load.
• Own observability end-to-end: SLIs/SLOs, structured logging, distributed tracing, and alerting, driving incidents to root-cause resolution.
• Instrument user-facing metrics and feature adoption signals to close the feedback loop between engineering decisions and product outcomes.
• Product mindset with hands-on go-to-market experience, partnering with Product Managers to shape roadmap priorities, drive iterative development cycles, and translate business goals into sound technical decisions.

Nice to have:

• Design and implement enterprise-grade account and organization data models, including multi-tenant architectures supporting organizations, workspaces, users, and permissions.
• Architect and implement RBAC or ABAC permission systems that support fine-grained access control across APIs, services, and UI surfaces.
• Develop enterprise readiness features such as audit logs, admin controls, permission management, and compliance-oriented access patterns.
• Experience building or maintaining systems operating with large datasets.
• Experience working with Monorepo setup.

About Bluefish:

Bluefish believes that AI represents the next major chapter of the internet – and that consumers will increasingly use AI to consume information and media online. On this new AI internet, brands will need new tools and technologies to tell their stories to consumers online – and a new marketing ecosystem will be created around AI. Bluefish is building the platform that helps brands engage consumers on this new AI channel, with powerful enterprise tools to manage AI brand safety and engage consumers with thoughtful and personalized AI marketing experiences.

The Bluefish team is a tight-knit group of mar-tech industry veterans who previously helped build foundational ad-tech platforms now owned by Meta and Microsoft. Bluefish, the leading AI marketing platform for the Fortune 500, recently announced a $43 million Series B growth financing co-led by Threshold Ventures and NEA with participation from multiple enterprise investors including Amex Ventures, TIAA Ventures, Salesforce Ventures, and continued participation from Bloomberg Beta. We are a globally distributed team, with business operations based in New York City and engineering based in Europe and New York.

Why Bluefish & Our Values:

• Unique opportunity to join on the ground floor of a fast-moving startup building at the center of AI.
• Tackle challenging and abstract problems while disrupting the $300BN legacy mar-tech industry.
• Join an experienced high-performing team where you will have immediate ownership and impact.
• Experience a true meritocracy with significant career growth upside as the business scales.

Our Values:

• Demonstrated grit and resourcefulness - you find creative solutions, adapt quickly, and aren’t afraid to roll up your sleeves in a fast-paced, evolving environment.
• Thoughtful and strategic thinker with the ability to anticipate needs, ask the right questions, and deliver insights that truly drive value.
• Proven ability to collaborate across functions and roles, fostering open communication and shared ownership of outcomes.
• Commitment to craftsmanship - you take pride in delivering high-quality work, paying attention to the small details while keeping the big picture in mind.
• Self-starter with a proactive mindset and a strong sense of accountability - able to drive projects forward independently while staying aligned with team goals.
• Comfortable navigating ambiguity and learning new tools, processes, or technologies to get the job done.