Senior Backend Engineer (.NET and Python)

Location: Sofia, Bulgaria — Hybrid

Company

hirify.global is an international engineering firm helping businesses operate with AI at the core, with more than 6,000 experts worldwide.

What you will do

• Design and build backend services and APIs in C#/.NET and Python for an AI gateway, access control, rate and spend limits, failover, and upgrades.
• Integrate with enterprise identity, secrets management, and AI services across Azure, AWS, and GCP.
• Build for performance and resilience through streaming, concurrency, caching, load testing, and graceful degradation.
• Store and serve audit, usage, and cost data reliably; instrument systems with traces, metrics, logs, alerts, and runbooks.
• Build infrastructure as code and CI/CD pipelines with supply-chain security.
• Work spec-first with AI coding agents, review generated code, write production-grade code, and contribute to technical proposals.

Requirements

• 6+ years of professional backend engineering experience, including production experience with both C#/.NET and Python and strong expertise in at least one.
• Experience designing APIs and distributed systems, including REST, gRPC, asynchronous processing, queues, idempotency, relational databases, and NoSQL data stores.
• Production experience with at least one major cloud platform — Azure, AWS, or GCP — and working experience with a second, plus Terraform or equivalent, containers, and Kubernetes.
• Knowledge of OAuth 2.0, OpenID Connect, secrets management, least privilege, network isolation, and data protection.
• Experience with OpenTelemetry, Prometheus/Grafana, or a cloud-native observability equivalent.
• Spec-driven development experience, including writing specifications, interface contracts, and acceptance criteria before coding; daily use of AI coding agents such as GitHub Copilot, Claude Code, or Cursor; and rigorous review and testing of generated code.
• Working understanding of LLM applications, including model APIs, streaming, and tool calling.
• Fluent English and the ability to explain and defend designs to client CTOs or security teams.

Nice to have

• Experience with API gateways and reverse proxies such as Azure API Management, YARP, Envoy, or LiteLLM.
• Experience with policy engines such as Open Policy Agent and audit-grade logging.
• Experience building high-throughput streaming APIs.
• Experience in regulated industries such as financial services, pharma, or telco.
• Consulting or client-facing delivery experience and contributions to open-source projects.

Culture & Benefits

• Respectful and inclusive environment with equal opportunities regardless of personal characteristics.
• Encouragement to share ideas and contribute to a sense of belonging.
• Hybrid work arrangement in Sofia.

Hiring process

• Submit a CV and discuss core skills and career goals during a talent call.
• Complete a technical interview focused on experience, strengths, and approach to work.
• Some roles include a customer interview before the offer and onboarding.