Customer.io

Senior Fullstack SDK Engineer

Americas Remote · Senior

Sponsorship not specified$150k-$200kDetected 1 day ago

SwiftKotlinReactiOSAndroidNode.jsFull-Stack DevelopmentAPI DevelopmentLLMsAgentic AITest AutomationCommunicationCollaboration

About the role

We help teams send smarter, more relevant messages using real-time behavioral data.

Build and evolve Customer.io's SDKs across platforms - including Android, iOS, Node, and Go - and the developer tools that support them
Lead SDK initiatives end to end: set technical direction, write the code, manage the release, and own the outcome
Partner closely with product and design to turn loosely defined goals into a great developer experience
Expert-level competency in at least one established programming language, with strong software design and API design fundamentals
Experience building and evolving mature, production-quality software, with a clear understanding of how systems fit together and how other developers consume them
High autonomy in ambiguous environments - you clarify the problem, validate its value, and drive implementation without close direction
No gotchas, no trick questions - just a clear, human process designed to help both of us make an informed decision.
We strive to build an inclusive team culture, implement bias-free hiring practices, and develop community partnerships to expand our global impact.
If you're excited by what you read and want to build software that makes communication better for everyone-apply now.

Strong written and verbal communication, with the ability to explain technical decisions and tradeoffs clearly
Ability to work effectively across multiple languages and stacks
prior experience in every language we support (Swift, Kotlin, Node, Go) is not required

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.
Hiring Manager & AI Skills Interview (60 mins)
We'll explore ownership, autonomy, and collaboration, then dig into how you actually use AI in your day-to-day workflow.
Practical AI-Enabled Coding Round (60 mins)
A live, collaborative session where you'll extend a sample SDK using AI tools.

Hi, I'm Josh, Engineering Manager at Customer.io.
About Customer.io
Customer.io powers automated communication that people actually want to receive.

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.

Our inclusive benefits package supports your well-being and growth, including 100% coverage of medical, dental, vision, mental health, and supplemental insurance premiums for you and your family.
See full benefits here →
We commit to using our influence to increase inclusion and equity within the tech industry.
We also offer 16 weeks paid parental leave, unlimited PTO, stipends for remote work and wellness, a professional development budget, and more.

This listing is sourced directly from Customer.io's careers page and normalized into a canonical job model.