Senior Software Engineer II, Flywheel Foundations

However you identify or whatever your path here, please apply if you see a position that makes your heart skip a beat. Come join us and help us build a global company where we're all proud to belong.

Flywheel Context (Foundations) Team UK - we're open to fully remote, hybrid or office based - whatever works best for you!

Hub Spot is building the next generation of AI-powered experiences across our go-to-market platform. We’re hiring a Senior Software Engineer II to join the Flywheel Context team - a foundational group responsible for building the data and context layer that powers intelligent AI assistants and agents across Hub Spot.

This is a backend-leaning, data-intensive role focused on building durable production systems. You’ll design and ship the infrastructure that enables AI systems to access relevant customer context, process large volumes of CRM data, and deliver high-quality outputs at scale.

If you’re excited about building foundational platforms that unlock smarter AI across an entire product ecosystem, this role is for you.

• Design, build, and operate backend services that power context retrieval, enrichment, and insight generation across Hub Spot’s platform.
• Build systems for storing, processing, and retrieving high-volume GTM data (e.g., contact history, CRM activity, behavioral signals).
• Develop scalable data processing and streaming solutions to support AI-driven use cases.
• Create reusable platform capabilities and APIs that enable other product teams to build smarter AI assistants and agents.
• Contribute to evaluation and quality frameworks to ensure context accuracy, reliability, and performance.
• Collaborate closely with platform teams and downstream product engineering teams to integrate capabilities into real customer experiences.
• Own end-to-end delivery: architecture, implementation, observability, performance, and iteration in production environments.

• Strong track record shipping production backend systems as a senior engineer, with ownership from design through operation.
• Professional experience building maintainable, scalable backend services (Java preferred).
• Strong data background and experience working with large datasets, data pipelines, and data-intensive systems.
• Experience building or integrating AI/ML-adjacent systems in production (e.g., retrieval pipelines, embeddings, ranking systems, model-backed services, or similar).
• Experience operating systems at scale, including performance optimization and reliability considerations.
• Strong engineering fundamentals: system design, testing, debugging, observability, and operational excellence.
• Product mindset - comfortable collaborating cross-functionally and building platform capabilities used by other engineering teams.

• Experience with search, retrieval, ranking, or relevance systems.
• Familiarity with RAG architectures, vector search, or hybrid retrieval approaches.
• Experience with streaming technologies or event-driven architectures.
• Some frontend experience or willingness to contribute across the stack when needed.

AI systems are only as good as the context they can access. This team is responsible for unlocking Hub Spot’s greatest competitive advantage: the depth and richness of customer data across the platform.

Your work will directly impact how intelligent and reliable Hub Spot’s AI agents become and enabling a true 360° understanding of customers and accelerate AI innovation across Flywheel.

If you need accommodations or assistance due to a disability, please reach out to us using this form.

At Hub Spot, we value both flexibility and connection. Whether you’re a Remote employee or work from the Office, we want you to start your journey here by building strong connections with your team and peers. If you are joining our Engineering team, you will be required to attend a regional Hub Spot office for in-person onboarding. If you join our broader Product team, you’ll also attend other in-person events, such as your Product Group Summit and other gatherings, to continue building on…