Lead Software Engineer - Mobile Channels

Klaviyo Klaviyo · Enterprise · Boston, MA · Engineering

Lead Software Engineer for Klaviyo's Mobile Channels team, focusing on building and scaling high-throughput messaging infrastructure (SMS, RCS, WhatsApp). The role involves technical leadership, architecture, system design, and ensuring reliable delivery while managing compliance and regulations. A key aspect is transforming workflows by putting AI at the center, building smarter systems and ways of working.

What you'd actually do

  1. Lead a team of engineers building and scaling Klaviyo's mobile messaging infrastructure across SMS, RCS, WhatsApp, and future channels
  2. Own and drive the architecture of key components in the mobile messaging pipeline — from message ingestion and routing to provider delivery and status tracking
  3. Design and implement scalable, high-throughput services in Python and Go
  4. Build systems that ensure reliable delivery at scale while managing carrier compliance, opt-in/opt-out requirements, throughput limits, and international messaging regulations
  5. Transform workflows by putting AI at the center, building smarter systems and ways of working from the ground up

Skills

Required

  • Backend systems design
  • Distributed systems
  • System design
  • Scaling infrastructure
  • AWS
  • Python
  • Go
  • High-throughput systems

Nice to have

  • SMS/MMS infrastructure
  • RCS
  • WhatsApp Business API
  • Carrier integrations
  • Telecom APIs
  • Messaging compliance
  • AI experimentation
  • AI tool exploration

What the JD emphasized

  • 8+ years of engineering experience
  • Proficient in Python and/or Go
  • Experienced working with high-throughput distributed systems
  • Skilled in system design and scaling infrastructure using AWS
  • 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.

Other signals

  • AI is a core part of the role's responsibilities
  • The role will build AI systems
  • The role will use AI tools to improve workflows