Senior GTM Partner Systems Engineer

About the role

At Klaviyo, we value the unique backgrounds, experiences and perspectives each Klaviyo (we call ourselves Klaviyos) brings to our workplace each and every day. We believe everyone deserves a fair shot at success and appreciate the experiences each person brings beyond the traditional job requirements. If you're a close but not exact match with the description, we hope you'll still consider applying. Want to learn more about life at Klaviyo? Visit klaviyo.com/careers to see how we empower creators to own their own destiny. As a Senior Systems Engineer on the GTM Systems Partner team, you will own the enterprise systems end-to-end - from understanding the business process, to engineering the right solution, to measuring whether it moved the needle. You will own delivery, platform health, and code quality across a GTM stack - including the external-facing partner portal by sizing and building features, maintaining platform health, and shipping reliable integrations across our GTM stack. This is a high-craft, high-ownership role for someone who wants to write great code, drive quality standards, and see their work translate directly to Klaviyo's goals. You will partner closely with cross-functional stakeholders to ensure that the systems you build are scalable, maintainable, and aligned with the strategic priorities of the business. You will act as a technical leader, guiding best practices and fostering a culture of quality and continuous improvement across the team.

Key facts

What you'll do

Own delivery of Salesforce solutions - Apex, Lightning Web Components, Flow, and integrations - from sprint planning through deployment, applying engineering best practices (DRY, SOLID, KISS) and holding a high bar for code quality through GitHub-based pull request reviews.

Develop and maintain integrations between Salesforce and the broader GTM stack, including the external-facing partner portal; ensure reliable, secure data flows across partner management and payments while prioritizing strict access and permission governance.

Triage and resolve high-impact platform and data issues quickly, owning the technical fix and communicating status clearly to the Product Owner and business partners.

Use AI tools as part of your daily engineering workflow to ship faster, explore unfamiliar systems, and automate repetitive work - and help teammates build the same habits.

Partner with the Product Owner and Architect during story refinement to size work accurately, surface technical constraints early, and ensure stories are fully ready before sprint planning.

Mentor junior developers through code reviews, engineering standards, and pairing - accelerating the team's shift to professional-grade, git-based development practices.

Champion platform reliability and operational excellence by monitoring system health, driving observability, and implementing improvements that reduce toil and prevent recurring incidents.

Collaborate with security and compliance stakeholders to ensure all integrations and data flows meet organizational standards and regulatory requirements.

Take ownership of the full delivery lifecycle, from initial discovery and scoping through implementation, testing, and post-deployment validation.

Contribute to architectural decisions that enable long-term scalability and a maintainable codebase across the GTM systems partner ecosystem.

Participate in on-call responsibilities to support production issues and ensure timely resolution of critical platform incidents.

Drive continuous improvement by analyzing metrics, gathering feedback from stakeholders, and proposing actionable enhancements to the partner portal and related systems.

Work closely with data and analytics partners to ensure that the systems we build provide accurate, timely, and actionable insights for business stakeholders.

Promote a culture of learning, experimentation, and knowledge sharing within the GTM Systems team and across the broader organization.

Requirements

8+ years of professional software engineering experience with a strong track record of delivering complex solutions in a production environment.

Strong experience with Salesforce development, including Apex, Lightning Web Components, and Flow, as well as integrations into and out of the Salesforce platform.

Solid understanding of enterprise integration patterns and experience building and maintaining integrations with external systems, including partner management and payments platforms.

Proficiency with Git, GitHub workflows, and modern software development practices, including code reviews, testing, and CI/CD principles.

Experience with cloud platforms and infrastructure as code, with a demonstrated ability to manage and operate scalable, reliable systems.

Strong problem-solving skills and the ability to triage and resolve high-impact issues in a fast-paced, production environment.

Excellent communication skills and the ability to partner effectively with product, design, and business stakeholders to clarify requirements and align on solutions.

A commitment to writing clean, maintainable, code and mentoring others to uphold high engineering standards across the team.

Practical notes

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