Senior Software Engineer - Email Channel

Senior Software Engineer - Email Channel position at Customer.io. The role involves owning the email channel end to end, from infrastructure to product surfaces. Experience in building scalable, distributed systems in Go, and product-facing frontend features in React or similar frameworks is required.

Requirements

• 7+ years of experience building scalable, distributed systems in Go (or similar statically typed languages)
• Experience building product-facing frontend features in React or similar frameworks, with attention to UX quality and polish
• Comfort working in cloud-native environments (AWS, GCP)
• Familiarity with relational databases (we use MySQL primarily) and an understanding of performance tradeoffs
• Familiarity with high-volume email sending concepts: bounce handling, feedback loops, and delivery event processing
• Working knowledge of email authentication standards — SPF, DKIM, DMARC — and how they affect deliverability
• Comfortable reasoning about sender reputation, IP warm-up, and ISP behavior at scale
• Experience with observability tooling and operating production systems
• Experience building or consuming APIs that handle high-throughput async workloads
• A bias for action over perfection, and pride in owning technical decisions

Benefits

• 100% coverage of medical, dental, vision, mental health, and supplemental insurance premiums
• 16 weeks paid parental leave
• Unlimited PTO
• Stipends for remote work and wellness
• Professional development budget