Your expertise: * Senior backend engineering experience with strong command of C# 12 on .NET 8 and ASP.NET Core (nullable enabled, warnings-as-errors, StyleCop) * Solid experience building microservices and persistence with PostgreSQL 15 via Entity Framework Core 8 (Npgsql) and Redis 7 caching * Proven ability to own services end-to-end and ship to production, with high autonomy and sound technical decision-making without close supervision * Upper-Intermediate English level or higher, with confident written and spoken communication for a fully distributed, English-only team
Will definitely be a plus: * Experience with internal service platforms / shared infrastructure libraries (health checks, querying, rate limiting, internal RPC clients) * AWS (S3 via AWSSDK), LocalStack, Docker / docker-compose * JWT Bearer and Google Auth * CI / CD with Jenkins, Artifactory-hosted NuGet feeds, and Bitbucket * Real-time/secure communication * Startup or early-stage product experience
What’s in it for you? * Opportunity to deal with top-notch technologies and approaches in a world-leader product company with millions of customers * Opportunity to make a difference for online privacy, freedom of speech, and net neutrality * Decent market rate compensation depending on experience and skills * Developed corporate culture: no micromanagement, culture based on principles of truth, trust, and transparency * “You build it, you own it” mentality in most contexts * Support of personal and professional development * coverage of costs of external trainings, conferences, professional literature * support of experienced colleagues * in-house events and trainings * regular knowledge sharing in teams * English classes and speaking clubs * Life-balance support * truly flexible schedule, no time-tracking at all * 25 working days of vacation * 5 days of paid sick leave per month (if necessary) without providing a medical certificate * generous maternity / paternity leave program * Professionally strong environment, friendly and open atmosphere, ability to influence the product development and recognition for it
You will be involved into: * Build and own backend services for Thunderbolt end-to-end — designing, implementing, and operating microservices on the internal service platform, from design and implementation through release and maintenance * Take responsibility for code quality, architecture, and the overall health of the backend codebase * Proactively propose and drive improvements rather than waiting for direction, and collaborate closely with Mobile, Web, and UX to ship a cohesive product
About the company and project:
ZONE3000 is a 2400+ people family that forms a new cultural code in the software development business. For 25 years we have been focusing on the highest quality of projects and empowering people to think big and make a difference. We are looking for talents who want to create and improve technological solutions for tomorrow and make things as best possible.
On behalf of our client Thunderbolt LLC (thunderbolt.com) — a next-generation business communication platform that combines secure, domain-based messaging with AI-powered automation to help businesses communicate with their clients smarter and safer, ZONE3000 is looking for Software Engineer (.NET Backend) .
Thunderbolt LLC is a US-headquartered startup built around Thunderbolt — a secure business communication platform. The product enables voice and video calls and chat messaging using a company’s domain name instead of a phone number or email, with end-to-end encryption, domain-ownership verification, and DNSSEC protection.
Thunderbolt combines secure, domain-based communication with AI-powered automation, giving businesses a unified platform to manage client conversations across their website and beyond.
The team is organized across four core functions — Mobile, Web, Backend, and UX — and collaborates closely to evolve the product from a domain-based communication tool into a full AI-powered business communication platform.
As a Senior Software Engineer (.NET Backend) at Thunderbolt, you will build and own backend services for Thunderbolt end-to-end — designing, implementing, and operating microservices on the internal service platform, from design and implementation through release and maintenance. Take responsibility for code quality, architecture, and the overall health of the backend codebase. Proactively propose and drive improvements rather than waiting for direction, and collaborate closely with Mobile, Web, and UX to ship a cohesive product.