Engineering Manager - SMS Delivery

The SMS Delivery team owns Klaviyo's mobile sender platform: the systems that allow brands to select, register, and activate the sender identities they use to send messages on SMS, RCS, WhatsApp, and future mobile channels. Mobile is one of Klaviyo's fastest-growing product areas, and this team's platform sits in the path of every customer who adopts a mobile channel.

As Engineering Manager, SMS Delivery, you will lead a team of backend and full-stack engineers building this platform. You will own the team's roadmap, technical direction, and operational health. You will work closely with Product, Compliance, Data Science, and adjacent mobile channel teams to deliver self-serve sender registration and KYC, registration lifecycle visibility for customers, and the cross-channel sender management framework that future channels will build on.

This is a hands-on technical leadership role. You will set direction, lead design reviews, mentor senior engineers, and contribute to code where it has the most leverage.

• Lead, mentor, and grow a team of engineers building Klaviyo's mobile sender registration, KYC, and lifecycle platform. Own hiring, performance, career development, and team culture.
• Define the team's roadmap with your Product partner. Sequence and deliver work that improves mobile activation and time-to-first-send for customers.
• Drive architecture across sender management, provider integration, mobile account lifecycle, and the cross-channel KYC platform.
• Evolve the team's platform into a unified, channel-agnostic framework that new mobile channels can adopt without rebuilding foundational logic.
• Move sender registration into automated, in-app, API-driven workflows that customers can complete on their own across markets and sender types.
• Raise the bar on reliability and observability with meaningful SLOs, actionable alerting, end-to-end testing, and registration lifecycle telemetry your team and customers can rely on.
• Stay engaged with the code through design reviews, code reviews, and the occasional prototype to de-risk complex decisions.
• Partner across the Mobile Channels organization with the WhatsApp, RCS, Compliance, and Data Science teams to deliver cohesive customer outcomes.
• Put AI to work in how the team operates and what the platform delivers, including automated registration triage, anomaly detection, and agentic operations for sender management.

• 8+ years of software engineering experience, with 3+ years of engineering management experience leading teams that build and operate production systems.
• Comfortable contributing to design documents, reviewing code, and debugging complex production systems. Proficient in Python and/or Go, and able to learn the other quickly.
• Strong distributed systems background, with experience designing and operating high-throughput, event-driven systems on AWS, including stateful workloads, asynchronous processing, third-party API integration, and the failure modes those bring.
• Experience owning a platform: defining domain boundaries, designing APIs that other engineering teams adopt, and earning that adoption.
• Strong product and business judgment. You can translate ambiguous goals into sequenced engineering plans and reason clearly about tradeoffs between speed, scope, and quality.
• Proven coach and team builder. You hire well, give direct and useful feedback, and have grown engineers from senior to lead.
• Clear communicator. You can articulate complex technical concepts to engineers, product managers, and executives in writing and in conversation.
• You have already experimented with AI in your work and are excited to bring it to a larger team and platform footprint.
• Collaborative and self-led. You thrive in a hybrid, high-autonomy environment and ship value early and iterate.

• Experience with SMS, RCS, or WhatsApp ecosystems, including carrier registration, opt-in and opt-out semantics, and telecom APIs and providers.
• Background in regulated systems where compliance, identity, or KYC is a first-class concern (telecom, payments, fintech, healthcare).
• Experience evolving services out of a monolith into independently deployable, domain-owned services.
• Experience with multi-region deployments, data residency requirements, or large-scale data migrations completed with minimal downtime.

• Python, Go
• AWS, Terraform, DynamoDB, Redis, SQL
• Kafka

This is a hybrid role based in Boston, with 3 days in office and 2 days remote per week.