Senior Software Engineer - Amplify

Team Overview:

At Klaviyo, we value the unique backgrounds, experiences and perspectives each 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  to see how we empower creators to own their own destiny.

The Amplify team builds the internal platforms, automation, and AI-driven systems that power how Klaviyos work every day. As a Senior Software Engineer on Amplify, you will:

• Design, build, and own complex internal products and platforms, including internal web applications, APIs, data and event pipelines, and AI-powered workflows that directly impact how Sales, Marketing, Customer Service & Success, R&D, and Finance teams operate day to day.
• Independently lead the end-to-end lifecycle of projects and features – from discovery and design through implementation, rollout, and long-term ownership.
• Translate real operational problems into scalable, maintainable solutions. You’ll partner closely with internal customers to understand their workflows and constraints, then design pragmatic, AI-first software that measurably improves throughput, quality, and reliability of their work.
• Own the technical and architectural evolution of parts of the Amplify platform, anticipating scalability, reliability, and observability needs as usage grows and as Klaviyo’s AI strategy evolves.
• Establish, refine, and uphold SLOs and operational health for the systems you own, ensuring they are reliable, observable, and fit for internal customer needs, including incidents, on-call participation, and follow-through on RCA actions.
• Drive an AI-first engineering workflow. You’ll use modern AI tools (e.g., OpenAI/Anthropic/Gemini models, Claude Code, Cursor, Copilot, etc.) for design, coding, testing, and documentation, and help define best practices for how Amplify engineers use AI to safely and efficiently ship software.
• Create and evolve shared patterns, tools, and processes that make it easier for Amplify and adjacent teams to build internal tools and AI agents consistently and at high quality (e.g., templates, SDKs, integration patterns, evaluation harnesses, observability standards).
• Mentor and uplevel other engineers on the team through design reviews, pairing, feedback on technical documents, and by modeling excellent engineering practices that leave the codebase, systems, and processes better than you found them.
• Collaborate deeply with Product, Design, Data, and operational stakeholders to define requirements, trade-offs, and success metrics, ensuring Amplify’s systems are solving the highest-value problems with clear, measurable outcomes.
• Transform workflows by putting AI at the center, building smarter systems and ways of working from the ground up.

• You are passionate about building software effectively and for the long term, balancing technical quality, velocity, and business impact.
• BA or BS Degree in Computer Science, related field, or equivalent experience.
• You typically bring 6+ years of hands‑on software development experience building and operating highly available, full‑stack SaaS products at scale, or have demonstrated equivalent proficiency and impact.
• You are independently responsible for the full lifecycle of complex projects or features, including discovery, technical design, implementation, rollout, and ongoing maintenance. You provide clear technical direction for others involved.
• You have deep expertise in one or more areas of modern web architecture (e.g., backend services, data pipelines, internal tools, AI/ML infrastructure) and a strong understanding of scalable, multi‑tenant design patterns.
• You’ve already experimented with AI in work or personal projects, and you’re excited to dive in and learn fast. You’re hungry to responsibly explore new AI tools and workflows, finding ways to make your work smarter and more efficient.
• You are an AI‑native engineer. You regularly use AI tools…