Senior Software Engineer II, Messaging Core

At Hub Spot, we’re on a mission to help millions of organizations grow better. Our platform is used by businesses worldwide to manage marketing, sales, service, and operations. We build flexible, secure, and empowering products for both our customers and engineering teams, fostering autonomy, curiosity, and a workplace where anyone can thrive.

The Messaging Product Group builds the apps and infrastructure behind marketing Email, SMS, and Whats App in Hub Spot, powering billions of messages per month. Messaging Core Backend underpins every Messaging product. As a Senior Software Engineer II, you’ll design and evolve distributed backend systems that support asset creation, publishing, and cross‑product consistency.

• Design and build backend services and APIs for marketing Email, SMS, and Whats App creation, management, and publishing.
• Own and evolve shared infrastructure used across all Messaging services.
• Lead complex, cross‑team projects (typically 3–6 months) spanning multiple services, data stores, and product areas.
• Take a data‑driven approach to reliability and performance.
• Contribute to, or lead, database and infrastructure initiatives such as keyspace migrations in partnership with platform teams.
• Debug and resolve production issues across the stack, using metrics, logs, and tracing to improve architecture, alerting, and runbooks.
• Drive technical design for new features and refactors, author design docs, review peers’ designs, and ensure solutions are scalable, maintainable, and aligned with broader Messaging architecture.
• Mentor and elevate other engineers through code reviews, pairing, and informal coaching on distributed systems, reliability, and product thinking.
• Collaborate with frontend, infra, and product partners across Messaging and adjacent teams to deliver end‑to‑end solutions.
• Participate in on‑call rotations and incident response, fostering shared ownership for reliability and sustainable on‑call practices.

• Deep backend engineering experience (typically 5+ years) building and operating production services in a modern microservice environment.
• A history of leading complex projects (3–6 months) as the primary backend engineer, owning design, implementation, rollout, and long‑term maintenance.
• Strong system‑design skills: building fault‑tolerant, horizontally scalable systems, balancing trade‑offs, and maintaining simplicity.
• Experience in service maturity: latency, test coverage, fault tolerance, and reliability.
• Comfort in high‑impact, data‑sensitive systems, including schema changes, migrations, and performance‑critical paths.
• Excellent collaboration and communication across engineering, product, and support, especially when clarifying ownership, triaging issues, and aligning behaviors.
• A growth mindset with evidence of multiplicative impact through mentoring, shared libraries, or patterns adopted by other teams.

• Experience in messaging or marketing technology (email/SMS/Whats App sending, campaign management, compliance, or analytics).
• Familiarity with MySQL, Vitess, and large‑scale data migrations in a sharded environment.
• Background working with CRM objects, properties, and usage data, including mirroring content into CRM.
• Experience with service maturity programs, error budgets, and SLO‑driven reliability work within a larger product line.
• Comfort collaborating with frontend teams on contracts and APIs, and with infra/platform teams on migrations and tooling improvements.

If you need accommodations or assistance due to a disability, please reach out using our accommodations form. Hub Spot values flexibility and connection. If you are joining our Engineering team, you will need to attend a regional Hub Spot office for in‑person onboarding; other product roles may attend additional in‑person events. Travel limitations or other accommodation requests should be discussed with your recruiter during the hiring process.

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