Senior Backend Engineer (.NET)

TL;DR

Senior Backend Engineer (.NET): Designing and implementing scalable, high-performance backend services and APIs for an agentic AI platform with an accent on scalability and security. Focus on optimizing system performance, solving real-world customer challenges, and integrating AI-driven workflows.

Location: Remote (Costa Rica or Serbia)

Company

Smartcat is an AI-powered platform enabling enterprises to build hybrid workforces of humans and AI agents to drive massive productivity gains.

What you will do

• Design, develop, and deploy backend services and APIs to solve real-world customer challenges.
• Optimize application performance, scalability, and security.
• Collaborate with product managers, frontend engineers, and DevOps for seamless service integration.
• Troubleshoot and resolve production issues efficiently.
• Participate in code reviews, knowledge sharing, and continuous learning.

Requirements

• 8+ years of professional software engineering experience.
• 3+ years of experience with .NET and C#.
• 2+ years of experience working in SaaS product companies.
• Advanced experience with MongoDB.
• Proven track record of writing and maintaining Unit and E2E tests.
• English: Upper-intermediate or higher proficiency (written and spoken) required.

Culture & Benefits

• Global, connected team operating across 30+ countries via a hub-and-spoke model.
• AI-native organization where AI is used across all departments to accelerate decision-making.
• High-growth environment (Series C) with 130% YoY growth.
• Culture focused on respect, diversity, and high performance.
• Remote-friendly work flexibility.