Senior iOS SDK Engineer

About the Role We are looking for aSenior iOS SDK Engineerto join our Mobile Observability team, responsible for designing, building, and maintaining ouropen-source Swift SDKacross Apple platforms (iOS, tvOS, watchOS, and macOS). This is ahands-on, SDK-first rolefocused 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 amodular Swift SDKused by developers across Apple platforms - Work oncrash reporting, hang detection, performance monitoring, and telemetry instrumentation - Build reliable mechanisms foroffline storage, batching, retries, and data deliveryunder mobile runtime constraints - Contribute toSDK architecture, API ergonomics, and backward compatibility - Design and evolve APIs with a focus onstability, clarity, and long-term compatibility - Debug complex issues across devices, OS versions, and app environments, includingthreading, memory, and lifecycle challenges - Develop and maintain capture services fornetworking, user interactions, and system events, leveraging frameworks such asMetricKit - Optimizestartup performance, binary size footprint, memory usage, and thread safety - Coordinate withcross-platform SDK teams (React Native, Flutter, Unity)to ensure native SDK changes do not introduce downstream breaking issues - Collaborate onOpenTelemetry alignment and upstream contributions - Partner with Product and Customer Success to incorporatedeveloper feedback Basic Qualifications - Strong proficiency inSwift, including async/await, structured concurrency, and protocol-oriented design - Experience building or maintainingSDKs, frameworks, or developer-facing libraries - Deep understanding ofApple platform runtime constraints:memory, threading, lifecycle, startup performance - Experience debugging issues inproduction mobile environments - Familiarity withAPI design, versioning, and SDK evolution - Understanding ofbinary compatibility and ABI stability - Strong advocate fortesting, reliability, and code quality - Excellent verbal and written communication skills - Experience usingGit and modern CI/CD workflows - Openness toAI-augmented engineering workflows Preferred Qualifications - Experience withObjective-C interoperability, runtime behavior, or method swizzling - Experience withSwift macrosorSwift Syntax - Familiarity withOpenTelemetry or observability concepts(traces, spans, logs) - Experience supportingmultiple Apple platformsfrom a shared codebase - Familiarity with system-level frameworks such asMetricKitorMXDiagnostic - Experience working in amulti-SDK ecosystemwhere platform changes affect cross-platform consumers - Contributions toopen-source projects - Experience supportingexternal developers / SDK users Additional Expectations Interview & Collaboration Our interview process includes live, synchronous conversations. Final stages may include anin-person meetingwith a team member (travel may be required). Engineering Workflow Evolution We work in an environment whereAI-assisted tools are increasingly part of engineering workflows. We value pragmatic, thoughtful use of these tools and expect candidates to be comfortable discussing their experience and perspective. Role Focus This role emphasizesSDK / framework / platform engineering, not application UI development. Work Culture & Travel We are a remote-first company. This role is open to candidates located anywhere in the U.S. or Canada. We believe in regular in-person connection and expect travel for team off-sites and colla