Senior Software Engineer

OneSpan

Barcelona, Spain

OneSpan is currently looking for a Senior Software Engineer (C/C++) to join our team in Barcelona.

You'll be part of a cross-functional team that owns the entire SDLC of our mobile security SDK—from architecture and development to QA and deployment. The SDK supports Android and iOS and is written in C, Kotlin, and Swift. We maintain high test coverage and deliver frequent releases through CI and automated build infrastructure. You'll also have the opportunity to work with and explore cutting-edge mobile security technologies.

Job Duties and Responsibilities

Design and develop new features and improvements for our mobile SDK.
Solve complex problems related to mobile security, performance, and reliability.
Develop application programming interfaces (APIs) to support mobile functionality.
Contribute to improving our QA processes, testing strategies, and automation, helping increase the reliability and robustness of our SDK.
Write clean, readable, and testable code, and cooperate with other teams to deliver well-architected and high-quality solutions.
Contribute to technical decisions, architecture discussions, and engineering best practices.
Help grow the engineering culture by sharing knowledge and mentoring others when needed.

Requirements

5+ years of professional experience developing for Android or iOS.
1-2 years of professional experience on projects in C language.
Experience with the full software development lifecycle, from requirements to delivery.
Drive improvements in QA practices, test automation, and quality processes to increase SDK reliability and reduce production issues.
Strong problem-solving and analytical skills.
Familiarity with memory safety practices, static analysis, secure coding standards, and threat modeling.
Ability to communicate effectively and collaborate with backend, product, and support teams.
Investigate and troubleshoot complex issues across different mobile devices, OS versions, and environments to provide technical support to customers.
Improve SDK reliability, performance, and integration experience for customers.
Good communication skills in English (spoken and written).
Stay updated with platform changes (iOS/Android/Web) and industry best practices

Nice to have:

Knowledge of Android Open Source Project.
Knowledge of these programming languages: C++, Objective-C, Swift, Java, and Kotlin.
Interest in mobile security and cybersecurity technologies.
Knowledge about cryptography and/or PKI infrastructure.
Experience with Git.
Experience with CI, automation and Jenkins.
Strong debugging and performance optimization skills.
Experience working in Agile development environments.
Curiosity, ownership mindset, and passion for learning.
Experience with observability frameworks (Sentry, Datadog...)
Fluency in Spanish