Senior Software Engineer II, Flywheel Foundations

London - UK

Monthly Salary: Not Disclosed

Posted on: 2 days ago

Vacancies: 1 Vacancy

Job Summary

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

Role Summary

HubSpot is building the next generation of AI-powered experiences across our go-to-market platform. Were 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 HubSpot.

This is a backend-leaning data-intensive role focused on building durable production systems. Youll 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 youre excited about building foundational platforms that unlock smarter AI across an entire product ecosystem this role is for you.

What Youll Do

Design build and operate backend services that power context retrieval enrichment and insight generation across HubSpots 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.

What Were Looking For:

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.

Nice to Have

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.
Cloud-native development experience (e.g. Kubernetes AWS/GCP).
Some frontend experience or willingness to contribute across the stack when needed.
Python experience.

Why This Role Matters

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

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

We know the confidence gapand impostor syndrome can get in the way of meeting spectacular candidates so please dont hesitate to apply wed love to hear from you.

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

At HubSpot we value both flexibility and connection. Whether youre 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 HubSpot office for in-person onboarding. If you join our broader Product team youll also attend other in-person events such as your Product Group Summit and other gatherings to continue building on those connections.

If you require an accommodation due to travel limitations or other reasons please inform your recruiter during the hiring process. We are committed to supporting candidates who may need alternative arrangements

Massachusetts Applicants: It is unlawful in Massachusetts to require or administer a lie detector test as a condition of employment or continued employment. An employer who violates this law shall be subject to criminal penalties and civil liability.

Germany Applicants: (m/f/d) - link to HubSpots Career Diversitypagehere.

India Applicants: link to HubSpot Indias equal opportunity policy here.

About HubSpot

HubSpot (NYSE: HUBS) is an AI-powered customer platform with all the software integrations and resources customers need to connect marketing sales and service. HubSpots connected platform enables businesses to grow faster by focusing on what matters most: customers.

At HubSpot bold is our baseline. Our employees around the globe move fast stay customer-obsessed and win together. Our culture is grounded in four commitments: Solve for the Customer Be Bold Learn Fast Align Adapt & Go! and Deliver with HEART. These commitments shape how we work lead and grow.

Were building a company where people can do their best work. We focus on brilliant work not badge swipes. By combining clarity ownership and trust we create space for big thinking and meaningful progress. And we know that when our employees grow our customers do too.

Recognized globally for our award-winning culture by Comparably Glassdoor Fortune and more HubSpot is headquartered in Cambridge MA with employees and offices around the world.

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HubSpot may use AI to help screen or assess candidates but all hiring decisions are always human. More information can be found here. By submitting your application you agree that HubSpot may collect your personal data for recruiting global organization planning and related purposes. Refer to HubSpots Recruiting Privacy Notice for details on data processing and your rights.

Required Experience:

Senior IC

Flywheel Context (Foundations) TeamUK - were open to fully remote hybrid or office based - whatever works best for you!Role SummaryHubSpot is building the next generation of AI-powered experiences across our go-to-market platform. Were hiring a Senior Software Engineer II to join the Flywheel Contex...