Senior / Strong Middle .NET Backend Developer (вакансія неактивна)

Project Description

We are actively expanding the team for our core product — an online vehicle marketplace where private sellers and dealerships can publish free listings, and buyers can browse available vehicles.

We are currently building mobile applications for iOS and Android based on our existing web service. Because time-to-market is critical, we are looking for an experienced .NET Backend Developer to help extend and optimize our existing REST API including Azure infrastructure. You will work closely with our Web team and our new Flutter Mobile Developer to ensure seamless app performance, reliable data synchronization, and fast search capabilities across our extensive vehicle catalog.

Technical Requirements

Core Backend Expertise

• Solid experience with the .NET stack, C#, and Entity Framework (EF) and Azure infrastructure.
• Strong understanding of building scalable and reliable architectures (clean code, SOLID principles, design patterns).

Database & SQL

• Deep knowledge of SQL (writing complex queries, optimization, and indexing).
• Understanding NoSQL concept and experience with corresponding DBs. MongoDB is preferable.
• Familiarity with DB migration and data synchronization.
• Experience working with large datasets (catalogs, complex filtering, and search), as our marketplace handles thousands of listings.

API & Networking

• Proven experience in designing, developing, and maintaining REST APIs.
• Understanding of API versioning and backward compatibility (our API will serve both web and mobile clients).

Authentication & Security

• Experience implementing secure authentication flows (JWT tokens, sessions, cookies).

Language Skills

• High level of English proficiency is required (Upper-Intermediate or higher), as all communication within our international team is conducted in English.

Key Responsibilities

• Extend the existing REST API to cover new mobile app requirements (advanced filtering, search, and listing creation).
• Design database architecture for new features using Entity Framework and write highly optimized SQL queries for fast retrieval of vehicle listings.
• Integrate backend services with Push Notification providers (e.g., Firebase Cloud Messaging) to ensure mobile users receive real-time notifications.
• Implement robust backend logic for media handling and storage (processing and saving vehicle photos uploaded by users via the app).
• Collaborate closely with the Flutter Mobile Developer to define API contracts and resolve integration challenges (especially regarding hybrid authentication flows).

“Nice-to-Have” Qualities

• Performance Tuning & Caching: Experience with caching solutions (e.g., Redis) and/or search engines (e.g., Elasticsearch) to speed up listing catalog load times.
• Domain Experience: Prior work with high-traffic marketplaces, classifieds, or e-commerce platforms.
• Cloud & Storage: Basic understanding of cloud storage solutions (Azure cloud services) for efficient image management.