Senior Software Engineer II - Backend, Flywheel

Location: London, United Kingdom

Department: Engineering

About the Role

At HubSpot, we're transforming how businesses grow through our Flywheel methodology, powering inbound marketing, sales, and CRM solutions for millions of customers worldwide. As a Senior Software Engineer II - Backend, Flywheel, you'll join our elite Engineering team to build the scalable backend systems that drive customer success. You'll architect robust services that integrate CRM data with marketing automation, enabling seamless experiences that accelerate the Flywheel. In this high-impact role, you'll tackle complex challenges like handling petabyte-scale data and real-time personalization, all while embodying our HEART culture of Humble, Empathetic, Adaptable, Remarkable, and Transparent. Your day-to-day will involve leading the development of microservices in Java or Python, optimizing APIs for low-latency performance, and collaborating cross-functionally to ship features that delight users. You'll mentor engineers, influence technical strategy, and ensure our platform scales effortlessly as HubSpot grows. With a focus on the Flywheel, you'll innovate on features that help customers attract, engage, and delight, directly contributing to revenue growth and customer retention. We thrive in a fast-paced, inclusive environment where ownership and experimentation are celebrated. If you're passionate about backend engineering, excited by CRM and inbound marketing, and ready to make a dent in the growth universe, join us to help shape the future of customer platforms at HubSpot.

Key Responsibilities

• Design, build, and maintain scalable backend services powering HubSpot's Flywheel platform
• Develop high-performance APIs that integrate CRM, inbound marketing, and sales tools
• Optimize database schemas and queries to handle massive data volumes from customer interactions
• Collaborate with frontend engineers, product managers, and data scientists to deliver end-to-end features
• Lead technical architecture decisions for Flywheel-related initiatives
• Mentor and guide junior engineers through code reviews and pair programming
• Implement robust monitoring, logging, and alerting for production systems
• Drive performance improvements and scalability enhancements across the backend stack
• Contribute to the evolution of HubSpot's growth culture by innovating on customer-centric solutions
• Participate in on-call rotations to ensure 99.99% uptime for critical services
• Experiment with new technologies to accelerate Flywheel's role in customer success

Required Qualifications

• Bachelor's degree in Computer Science, Engineering, or related field, or equivalent practical experience
• 8+ years of professional software engineering experience with a focus on backend development
• Deep expertise in building scalable backend systems using Java, Python, or Go
• Proven track record of designing and optimizing high-throughput APIs and microservices
• Strong experience with relational databases (e.g., PostgreSQL) and NoSQL solutions (e.g., DynamoDB)
• Hands-on experience with cloud platforms like AWS, including services like Lambda, ECS, and RDS
• Demonstrated ability to mentor junior engineers and lead cross-functional projects
• Excellent problem-solving skills and ability to thrive in a fast-paced, growth-oriented environment

Preferred Qualifications

• Experience working with CRM systems or inbound marketing platforms
• Familiarity with HubSpot's Flywheel methodology and customer growth strategies
• Contributions to open-source projects or publications in backend engineering
• Knowledge of event-driven architectures and message queues (e.g., Kafka, SQS)
• Previous experience in SaaS environments with millions of users
• Master's degree in Computer Science or related field

Required Skills

• Java or Python backend development
• RESTful API design and GraphQL
• Microservices architecture
• PostgreSQL and database optimization
• AWS cloud services
• Docker and Kubernetes
• CI/CD pipelines (e.g., Jenkins, GitHub Actions)
• Unit and integration testing
• Agile methodologies and Scrum
• Problem-solving and debugging
• Code review and collaboration
• Communication and stakeholder management
• Growth mindset and adaptability
• Mentoring and leadership
• Data structures and algorithms
• Event-driven systems
• Performance profiling and monitoring

Benefits

• Competitive salary and equity in a publicly-traded company
• Comprehensive health, dental, and vision insurance with 100% premium coverage
• Unlimited PTO and flexible work-from-anywhere policy
• 401(k) matching up to 5% of salary
• Professional development stipend for conferences, courses, and certifications
• HubSpot Academy access for ongoing learning in inbound marketing and sales
• Parental leave with full pay for primary and secondary caregivers
• Wellness programs including gym memberships and mental health support
• Quarterly Hackathons and innovation days to fuel creativity

HubSpot is an equal opportunity employer.