We are looking for a Senior .NET (WPF) Engineer to join a long-term product team working on a next-generation solution for ambitious and goal-oriented users. This product is designed for individuals striving for continuous personal and professional growth and is built as a platform-specific ecosystem with dedicated desktop and mobile applications.Responsibilities:Develop and maintain native Windows desktop applications using WPF and .NET.Design and implement secure offline-first solutions, ensuring data privacy and consistency on the client side.Apply encryption best practices, including implementing cryptographic protocols and securely managing keys.Handle complex multithreaded operations to ensure application responsiveness and stability.Integrate authentication systems using OAuth and SRP, and manage session security with JWT tokens.Create and maintain custom UI designs, ensuring a smooth and modern user experience.Ensure applications are always demo-ready and capable of being showcased during project milestones.Communicate regularly with the client to align on requirements, present updates, and discuss solutions.Collaborate with cross-functional teams, including product owners, designers, and QA.Participate in code reviews, architecture discussions, and help shape the technical direction of the project.Requirements:5+ years of experience with C#/.NET, with a strong focus on desktop application developmentSolid experience with the WPF framework and the MVVM architectural patternDeep understanding of multithreading, thread synchronization, and ThreadPool usage.Hands-on experience working with SQLite or other embedded local databasesProven ability to build and support offline-first applications with high reliabilityStrong knowledge of security concepts, including: Synchronous/asynchronous encryption, End-to-end encryption, Digital signatures.Familiarity with cryptographic algorithms such as AES-256-GCM, Ed25519, X25519, CSPRNG, Diffie-Hellman, etc.Experience with on-device encryption key generation and secure storage.Experience integrating OAuth and SRP authentication flows with third-party identity providers.Proficiency in JWT token management (access & refresh tokens).Experience building desktop applications with custom UI and publishing them to the Microsoft Store.Strong understanding of RESTful API integration and WebSockets communication.Excellent attention to detail and ability to consistently produce production-ready code.English: Intermediate strong or higher for direct client communication.Nice to have:Experience with CRDTs (Conflict-free Replicated Data Types) or conflict resolution in distributed systems.Familiarity with WPF MVVM libraries such as Prism, ReactiveUI, etc.Knowledge of CI/CD processes for desktop apps.Our Benefits:Professional growth: Individual development plan, mentorship, reimbursement for professional certifications and English lessons, access to professional courses in Corporate Learning Management System.Community: Tech community and knowledge-sharing events, English speaking club, corporate library and book club, volunteering and charity initiatives.Wellbeing: Medical insurance, regular medical check-ups, sport reimbursement, paid vacation and sick leave, mental health support, and events.Work environment: Fully-equipped offices, top-notch equipment, flexible work format, activities both in-office and online, Y-bucks, and access to the Yalantis store.Please note that feedback on the results of the CV review will be provided only in the event of a decision to consider your candidacy further.Otherwise, your data will be retained in the company’s CV database, and we will gladly contact you if a suitable vacancy becomes available. The consideration period is 7 working days.Before sending us your CV, you may read our Privacy Notice.Відгукнутись на вакансію