About the Role
We are looking for a Senior iOS SDK Engineer to join our Mobile Observability team, responsible for designing, building, and maintaining our open-source Swift SDK across Apple platforms (iOS, tvOS, watchOS, and macOS).
This is a hands-on, SDK-first role focused on building high-performance instrumentation libraries embedded in customer applications. It is ideal for someone who enjoys working close to the platform, solving difficult edge cases, and designing APIs that other developers rely on.
You’ll work on performance monitoring, telemetry capture, hang detection and crash reporting, all designed for minimal overhead and maximum reliability. You’ll collaborate across platform teams and contribute to evolving observability standards such as OpenTelemetry.
What You’ll Do
- Design, build, and maintain a modular Swift SDK used by developers across Apple platforms
- Work on crash reporting, hang detection, performance monitoring, and telemetry instrumentation
- Build reliable mechanisms for offline storage, batching, retries, and data delivery under mobile runtime constraints
- Contribute to SDK architecture, API ergonomics, and backward compatibility
- Design and evolve APIs with a focus on stability, clarity, and long-term compatibility
- Debug complex issues across devices, OS versions, and app environments, including threading, memory, and lifecycle challenges
- Develop and maintain capture services for networking, user interactions, and system events, leveraging frameworks such as MetricKit
- Optimize startup performance, binary size footprint, memory usage, and thread safety
- Coordinate with cross-platform SDK teams (React Native, Flutter, Unity) to ensure native SDK changes do not introduce downstream breaking issues
- Collaborate on OpenTelemetry alignment and upstream contributions
- Partner with Product and Customer Success to incorporate developer feedback
Basic Qualifications
- Strong proficiency in Swift, including async/await, structured concurrency, and protocol-oriented design
- Experience building or maintaining SDKs, frameworks, or developer-facing libraries
- Deep understanding of Apple platform runtime constraints: memory, threading, lifecycle, startup performance
- Experience debugging issues in production mobile environments
- Familiarity with API design, versioning, and SDK evolution
- Understanding of binary compatibility and ABI stability
- Strong advocate for testing, reliability, and code quality
- Excellent verbal and written communication skills
- Experience using Git and modern CI/CD workflows
- Openness to AI-augmented engineering workflows
Preferred Qualifications
- Experience with Objective-C interoperability, runtime behavior, or method swizzling