Senior Fullstack SDK Engineer

📋 Description

• Build and evolve Customer.io's SDKs (Android, iOS, Node, Go) and the tools that support them
• Lead SDK initiatives end to end: define direction, code, release
• Improve SDK delivery: CI, tests, versioning, publishing, release
• Partner with product and design to deliver a great developer experience
• Use AI agents to make multi-file changes across unfamiliar codebases
• Engage with engineers to understand their needs and provide empathy

🎯 Requirements

• Expert-level in at least one language with strong API design
• Experience building production-quality software and SDK consumers
• Fluency with LLMs and agentic coding tools (Claude, Cursor, Codex)
• High autonomy in ambiguous environments; define problems and drive implementation
• Strong written and verbal communication; explain technical decisions clearly
• Ability to work across multiple languages; prior experience in all languages we support not required

🎁 Benefits

• 100% coverage of medical, dental, vision, mental health, and family insurance
• 16 weeks paid parental leave
• Unlimited PTO
• Remote work and wellness stipends
• Professional development budget
• See full benefits here