Senior Backend Engineer

Details

About Customer.io

Over 7,500 companies - from scrappy startups to global brands - use our platform to send billions of emails, push notifications, in-app messages, and SMS every day. Customer.io powers automated communication that people actually want to receive.

We help teams send smarter, more relevant messages using real-time behavioral data. Under the hood: Go, React, Ember and AI help us ship fast and scale with confidence.

We’re looking for experienced backend engineers who care deeply about reliability, performance, and scalability. You’ll design, build, and evolve the systems that power communication at massive scale - while helping us push the boundaries of what great engineering can look like.

Responsibilities

• Design and build distributed systems in Go that help customers send timely, relevant messages at scale
• Collaborate across teams to debug issues and deliver reliable solutions
• Own problems end to end - from architecture and schema design to testing, deployment, and monitoring
• Share knowledge and raise the bar through sharing your progress publicly with short videos, thoughtful writing, and mentorship
• Leverage AI tools to prototype, move faster, and make better decisions

Requirements

• 7+ years of experience building scalable, distributed systems in Go
• Comfort working in cloud-native environments (AWS, GCP)
• Familiarity with relational databases (we use MySQL) and an understanding of performance tradeoffs
• Experience with observability tooling and operating production systems
• A bias for action over perfection, and pride in owning technical decisions

Compensation & Benefits

• Starting salary for this role is $150,000 - $200,000 USD (or equivalent in local currency) depending on experience and subject to market rate adjustment.
• 100% coverage of medical, dental, vision, mental health, and supplemental insurance premiums for you and your family
• 16 weeks paid parental leave
• Unlimited PTO
• Stipends for remote work and wellness
• Professional development budget

Our Process

• Application - We review everyone with care. Tell us why you're interested.
• Recruiter Call (30 mins) - Let’s chat about what you’re looking for and how we work.
• Behavioral Interview (60 mins) - Talk with one of our hiring managers about your experience, values, and working style.
• Technical Interview (60 mins) - A collaborative system design conversation focused on scaling challenges.
• Take-Home Assignment - Complete a short, realistic task similar to what you’d work on here.
• Assignment Review Call (60 mins) - Walk us through your work and discuss tradeoffs, priorities, and how you’d iterate.

All final candidates will be asked to complete a background check and employment verifications as part of our pre-employment process.

Customer.io recognizes the stifling impact of systemic injustice on diverse communities. We commit to using our influence to increase inclusion and equity within the tech industry. We strive to build an inclusive team culture, implement bias-free hiring practices, and develop community partnerships to expand our global impact.

Zoom is the only video conference platform that we use, virtual interviews will be conducted using the video capability (i.e., not via the chat), and offers will be extended in writing on official Customer.io letterhead. Please be vigilant in all of your job search activity, and if you have any questions please contact [email protected].

Join us!

We believe in empathy, transparency, responsibility, and, yes, a little awkwardness. If you’re excited by what you read and want to build software that makes communication better for everyone—apply now.