Senior Software Engineer, Backend - Customer.io

About the Role

Customer.io is looking for experienced backend engineers who care deeply about reliability, performance, and scalability. You will design, build, and evolve the systems that power communication at a massive scale, helping us push the boundaries of what great engineering looks like.

About Customer.io

Over 9,000 companies use our platform to send billions of emails, push notifications, in-app messages, and SMS every day. We help teams send smarter, more relevant messages using real-time behavioral data. Our tech stack includes Go, React, Ember, and AI.

What We Value

• Ownership: You own problems end-to-end, move fast, and thrive in ambiguity.
• Product Taste: You think like a user and care about the real-world value your systems provide.
• Healthy Skepticism: You bring rigor and creativity, prioritizing forward motion over rigid adherence to "the way things are done."

What You’ll Do

• Design and build distributed systems in Go to facilitate timely, relevant messaging at scale.
• Collaborate across teams to debug issues and deliver reliable solutions.
• Own the full lifecycle: architecture, schema design, testing, deployment, and monitoring.
• Share knowledge through public progress updates, writing, and mentorship.
• Utilize AI agents to manage multi-file changes by scoping work, prompting, and verifying outputs.

Requirements

• 7+ years of experience building scalable, distributed systems in Go (or similar statically typed languages).
• Comfort working in cloud-native environments (AWS, GCP).
• Familiarity with relational databases (MySQL) and performance tradeoffs.
• Experience with observability tooling and operating production systems.
• A bias for action and pride in technical ownership.

Compensation & Benefits

• Salary: $150,000 - $200,000 USD (or local equivalent).
• Insurance: 100% coverage of medical, dental, vision, mental health, and supplemental insurance for you and your family.
• Leave: 16 weeks paid parental leave and unlimited PTO.
• Perks: Remote work and wellness stipends, plus a professional development budget.