Back End Developer

Job Title: Senior Backend Engineer (Python)

Location: Sweden

Employment Type: Full-time

About the Role

We are looking for a Senior Backend Engineer with strong experience in Python-based backend systems and production-grade distributed architectures. You will play a key role in designing, building, and scaling high-performance services that support real-time data processing, cloud storage, and reliable APIs.

This role focuses on system design, scalability, and reliability rather than application-level scripting. You will collaborate closely with platform, data, and DevOps teams to deliver robust backend services used in production environments.

Key Responsibilities

• Design, develop, and maintain scalable backend services using Python and FastAPI
• Build and optimize RESTful and service-to-service APIs for high throughput and low latency
• Design production-grade database schemas and write efficient SQL queries
• Implement and manage asynchronous workflows and background jobs
• Work with event-driven systems for real-time data streaming
• Maintain data integrity and versioning across storage and ML-related assets
• Containerize services and contribute to CI/CD automation
• Monitor, debug, and improve system reliability and performance in production
• Participate in architecture discussions, code reviews, and best practice definition

Required Technical Skills

Core Programming & Frameworks

• Strong proficiency in Python (primary language)
• Solid experience with FastAPI
• Deep understanding of SQL and relational databases
• Experience with SQLAlchemy (ORM)
• Hands-on usage of Alembic for database migrations

Data & Messaging Infrastructure

• Experience with Apache Kafka or similar streaming platforms
• Redis for caching and performance optimization
• Celery or equivalent task queue systems
• Familiarity with Protobuf or other efficient serialization formats

Storage & Data Versioning

• Experience with Azure Blob Storage or similar cloud storage solutions
• Understanding of data versioning systems such as LakeFS (or equivalent concepts)

Deployment & Environment

• Strong experience with Docker & containerized applications
• Familiarity with uv (Astral) or modern Python dependency management
• CI/CD pipelines using GitHub Actions or similar tools

Monitoring, Logging & Observability

• Experience with Sentry for error tracking
• Working knowledge of Grafana for monitoring and dashboards
• Comfort using SQL admin tools for database monitoring and diagnostics

Production System Expectations

• Strong experience working with microservice architectures
• Ability to design scalable, fault-tolerant APIs
• Understanding of system reliability, failover strategies, and resilience
• Proficient with GitHub-based version control workflows
• Comfortable supporting and improving live production systems

Good to Have

• Experience with Kubernetes and container orchestration
• Exposure to ML model deployment or serving pipelines
• Experience building or integrating re-training pipelines
• Background in data platforms or ML infrastructure (not model training)

About HCL Sweden,

HCLTech has been supercharging progress in Sweden since 2008, delivering digital transformation, cloud, engineering, and cybersecurity solutions to major Swedish and global enterprises. It is recognized as a Top Employer in Sweden (#1 ranking) and listed among LinkedIn’s Top Companies 2025.