Type: Contract, per-project. Location: Remote — European Time Zones (CET/CEST) Availability: Contractor (40 hours per week) We are looking for a highly capable Android Software Engineer to join our Mobile SDK team and contribute to the core libraries that power our applications and the SDKs used by third-party device manufacturers and application developers. In this role, you will design and build features that perform a wide variety of network tests using Kotlin to access and exercise device hardware, C++ and Kotlin Multiplatform for cross-platform functionality, and Java to support legacy SDK products. You will work on SDK and application code, with a focus on designing well-structured APIs and building reliable, reusable software. Expectations for Success Develop and maintain SDKs that provide network testing functionality to third-party device manufacturers and application developers, including design, implementation, testing, documentation, deployment, development support, and maintenance. Build solutions with a focus on reliability, flexibility, portability, and code reuse. Integrate analytics to ensure optimal performance of deployed code. Collaborate on architecture, technology choices, and interactions with other core components, including frontend code, backend APIs, and distributed server infrastructure. Requirements 5+ years of software development experience with a solid foundation in data structures, algorithms, and design patterns. 3+ years of professional Android development experience, including experience with the application submission and review process. Experience working on multiple projects and the ability to learn new projects efficiently. Expertise in Kotlin and Java. Solid understanding of Android SDK development, threading, the Android Framework, networking frameworks (OKHTTP and TCP Sockets), and cross-platform library design. Strong understanding of networking fundamentals, including IP, TCP/UDP, HTTP/S, and WebSocket. Experience writing unit, integration, load, and stress tests. Proficiency with collaborative development workflows, including branches, pull requests, and continuous integration practices. Excellent debugging and troubleshooting skills. Strong time management skills and a self-driven work ethic. Preferred Qualifications Experience with C++. Experience with Swift. Contributions to open source projects.