Senior Native Android Engineer

Senior Native Android Engineer Country: IT STARTS HERE Santander ( www.santander.com ) is evolving from a global, high-impact brand into a technology-driven organization , and our people are at the heart of this journey. Together , we are driving a customer-centric transformation that values bold thinking, innovation , and the courage to challenge what’s possible. This is more than a strategic shift. It’s a chance for driven professionals to grow, learn, and make a real difference . Our mission is to contribute to help more people and businesses prosper . We embrace a strong risk culture and all our professionals at all levels are expected to take a proactive and responsible approach toward risk management. Our Chief Data & Artificial Intelligence Officer (CDAIO) division is building a world-class AI & Data team to make a difference in the lives of over 170 million people worldwide, through one of the largest banks in the world. We are undergoing one of the biggest transformations in our history and technology is at the heart of our strategy. Join our team to play a part in one of the most important technological projects for the financial sector in the world. Our mission is to contribute to helping more people and businesses prosper. We embrace a strong risk culture and all our professionals at all levels are expected to take a proactive and responsible approach toward risk management.  THE DIFFERENCE YOU MAKE CDAIO/ AI TECH is looking for a Senior Native Android Engineer based in Madrid. We are seeking a  Senior Native Android Engineer  to build advanced mobile solutions using  Kotlin  and  Jetpack Compose . You will deliver concrete products — production apps and  reusable, published SDKs  — within the Grupo Santander platform ecosystem, applying solid  software architecture  and  CI/CD  practices to ensure quality, maintainability, and scalability. This role works on  product SDKs  (e.g. an AI chatbot Compose component) that sit on top of the shared Santander Android platform, so the ability to read, integrate with, and reason about  platform building blocks  is essential. WHAT YOU’LL BRING Our people are our greatest strength. Every individual contributes unique perspectives that make us stronger as a team and as an organization. We’re enabling teams to go beyond by valuing who they are and empowering what they bring. The following requirements represent the knowledge, skills, and abilities essential for success in this role. Reasonable accommodations may be made to enable individuals with disabilities to perform the essential functions. Professional Experience A proven track record of at least 4 years of exclusive experience in native Android development. (Required). Experience on projects composed of libraries or that publish SDKs as a product. (Required). Demonstrable experience on projects with accessibility requirements.(Required). Experience in hybrid mobile technologies (React Native, Flutter, Xamarin) will not be considered. (Required). Experience on dual iOS/Android projects will not be considered, as the specific dedication to each platform cannot be determined. (Required). Personal or freelance projects will not be considered unless carried out in a collaborative team environment. (Required). Languages Native level in Spanish. (Required). English — minimum B2 (B2–C1 strongly preferred). This is a strict requirement: all code, KDoc, commits, PRs, changelogs, and platform documentation are written in English, and the SDK/platform is shared across international teams. (Required). Hard Skills Global: Mastery of  Kotlin  as a programming language. (Required). Strong knowledge of  visibility and extensibility  in Kotlin (internal boundaries, extension functions, API surface control). (Required). Knowledge of  Flow  and  Coroutines  (structured concurrency, StateFlow, dispatchers). (Required). Version control systems, preferably  Git . (Required). CI/CD tooling:  Bitrise  (or similar: GitHub Actions/Workflows, Jenkins…) (Required). Agile development methodologies. (Required). PR creation/review workflow and QA quality-control practices. (Required). Architecture: Solid knowledge of architecture patterns such as  MVVM  and  MVI  (immutable UiState + UiEvent). (Required). Dependency injection:  Koin  (or similar: Dagger/Hilt). (Required). Solid grasp of best practices:  SOLID  principles,  design patterns ,  Clean Architecture . (Required). Development, deployment, and  version control of internal or public libraries  (publishing to a Maven/Artifactory repository; awareness of binary/public-API compatibility validation). (Required). Data Access: Remote data libraries:  Retrofit  (or similar:  Ktor ,  OkHttp ). Experience with  REST  and  streaming over SSE  is a strong plus. (Required). Local data libraries:  Room ,  DataStore ,  SharedPreferences . (Required). JSON serialization with  kotlinx.serialization  (@Serializable DTOs). (Required). Jetpack Compose: Advanced mastery of  Jetpack Compose , with demonstrable experience defining and building complex components and complete screens in production apps. (Required). Strong knowledge of  Compose optimization and performance  (stability, recomposition control,  immutable collections  — kotlinx-collections-immutable). (Required). UX: creation of animations, transitions, and UI interactions. (Required). Creation of components or libraries for Compose (modeling of  custom state ). (Required). Screenshot testing  with  Paparazzi  or similar tools (e.g. Shot) to guarantee visual and functional UI quality. (Required). Accessibility: Deep knowledge of the  Jetpack Compose accessibility APIs . Ability to use  Semantics  to provide additional information to assistive tools such as screen readers. (Required). Knowledge of how to structure the view hierarchy so it is navigable by screen readers. (Required). Accessibility testing tools:  Tal