Senior Back-end/Python Developer

Optilon; Malmö kommun; On-site; SEK 900,000 - 1,100,000; Full time

Job summary

Optilon is seeking a Senior Backend / Python Developer to design, build, and evolve scalable backend services and data-heavy systems. You will own backend components, contribute to architecture, and help modernize platforms.

The role emphasizes Python backend development, APIs, databases, and data processing, with opportunities to contribute to Vue 3 frontend and AI-enabled solutions. Strong software engineering practices are essential, including testing and observability.

Qualifications

• 5+ years of professional software development with Python (backend focus).
• Master of Science in CS/Engineering/Data Science or related field.
• Strong Python skills and modern Python practices.
• Experience designing production-grade backend services and APIs.
• Strong understanding of software architecture, OOP, design patterns, and clean code.
• SQL experience with PostgreSQL and MS SQL Server; data-intensive apps.

Responsibilities

• Design, develop, test, and maintain production-grade Python backend services and APIs.
• Own backend components end-to-end from design to deployment.
• Design scalable, maintainable architectures and data-access patterns.
• Develop data-intensive services for ingestion, processing, and serving data.
• Work with relational databases (PostgreSQL, MS SQL Server) extensively.
• Implement automated testing, code reviews, documentation, and best practices.
• Contribute to CI/CD and modern deployment processes.
• Collaborate with frontend where relevant (Vue 3) and backend teams.
• Mentor mid-level and junior developers.

Skills

Python backend

APIs

SQL & databases

Software architecture

CI/CD

English proficiency

Education

M.S. in CS / Software Eng / Data Science

Tools

Docker

Kubernetes

Azure / cloud

.NET/C#

Flask

Pandas

Job description

We are looking for a Senior Backend / Python Developer to design, build, and evolve scalable backend services and data-intensive systems supporting our Supply Chain planning solutions.

This is a hands‑on senior engineering role with a strong focus on Python backend development, APIs, databases, system design, and data processing. You will take technical ownership of backend components and contribute to architectural decisions, platform modernization, and the development of reliable and maintainable production systems.

You will work with modern data and AI‑enabled solutions, including data pipelines and services supporting AI/ML workloads. While experience with AI technologies is valuable, the core of this position is strong software engineering and backend development in Python.

The role is suited to an experienced developer who enjoys solving complex technical problems, building production‑grade software, and contributing to both hands‑on implementation and long‑term technical direction.

Backend & Python Development

• Design, develop, test, and maintain production‑grade backend services and APIs primarily using Python

• Take technical ownership of backend components throughout their lifecycle, from design and implementation to deployment and continuous improvement

• Design scalable, maintainable, and well‑structured application architectures

• Develop data‑intensive services for ingestion, processing, transformation, and serving of data

• Work extensively with relational databases, particularly PostgreSQL and Microsoft SQL Server

• Design efficient data‑access patterns

• Apply strong object‑oriented design, software engineering principles, and clean coding practices

• Identify and resolve performance, scalability, and reliability bottlenecks

• Ensure high software quality through automated testing, code reviews, documentation, and engineering best practices

• Work with CI/CD and modern development and deployment practices

• Contribute to .NET‑based environments and integrations where relevant

• While the primary focus is backend development, opportunities to contribute to our Vue 3 frontend also exist

Data Engineering & AI‑Enabled Systems

• Develop backend services and data pipelines supporting AI/ML training, evaluation, and inference workloads

• Support the integration and productionisation of AI/ML models, engines and services

• Work with technologies and patterns such as RAG, vector databases, and MCP

• Collaborate with application owners to translate application and data requirements into reliable technical solutions

• Contribute to the design of AI‑ready data architectures while maintaining strong software engineering standards

Architecture & System Design

• Play an active role in backend architecture and technical design decisions

• Design systems for scalability, maintainability, reliability, security, and operational efficiency

• Define and promote engineering patterns, standards, and best practices for Python and backend development

• Evaluate frameworks, libraries, platforms, and technologies based on technical and business requirements

• Make pragmatic architectural decisions that balance delivery needs with long‑term maintainability

• Document architectural decisions, interfaces, and important technical designs

System Evolution & Modernization

• Modernize existing and legacy backend implementations

• Refactor complex or brittle components into maintainable, well‑tested solutions

• Improve the reliability, observability, performance, and scalability of existing systems

• Support migrations toward modern service and data architectures

• Identify and address technical debt in a structured and pragmatic way

• Help teams balance short‑term delivery requirements with long‑term technical sustainability

Technical Leadership & Collaboration

• Mentor and technically support mid‑level and junior developers

• Perform and contribute to code and architecture reviews

• Support technical planning, estimation, and solution design

• Work closely with product, consultancy, data, AI, and infrastructure teams

• Provide technical expertise in client‑facing consultancy and pre‑sales activities

• Communicate technical concepts, architectural decisions, risks, and trade‑offs clearly to both technical and non‑technical stakeholders

Required Qualifications

• At least 5 years of professional software development experience with Python, with a substantial focus on backend development

• Master of Science (M.Sc.) degree in Computer Science, Software Engineering, Data Science, Engineering, or another relevant technical field

• Strong knowledge of Python and modern Python software development practices

• Demonstrated experience designing and developing production‑grade backend services and APIs

• Strong understanding of software architecture, object‑oriented programming, design patterns, and clean‑code principles

• Strong experience with SQL and relational databases, preferably including PostgreSQL Microsoft and/or SQL Server

• Experience designing and implementing data‑intensive applications, data processing solutions, or data pipelines

• Experience with automated testing, version control, code reviews, and CI/CD practices

• Experience troubleshooting and optimizing production systems for performance, reliability, and scalability

• Experience working with modern deployment environments, preferably including containers and cloud‑based infrastructure

• Ability to independently drive technical tasks from requirements and design through implementation and production

• Strong communication skills and the ability to collaborate effectively across technical and business teams

• Professional working proficiency in English

Meriting Qualifications

• Experience with Flask, Pandas or other comparable Python backend frameworks

• Experience with asynchronous Python and distributed or event‑driven systems

• Experience with workflow orchestration and data engineering platforms

• Experience with Docker, Kubernetes, and cloud platforms

• Experience with Azure and the Microsoft technology ecosystem

• Experience with .NET/C#

• Experience with AI/ML production systems and model integration

• Experience with RAG architectures, vector databases, LLM-based applications, and MCP

• Experience with observability, monitoring, logging, and production operations

• Experience with Vue 3 or other modern frontend technologies

• Experience in Supply Chain, planning, optimization, or related data‑intensive business domains

• Previous experience mentoring developers or acting as a technical lead

What We Are Looking For

You are an experienced Python developer with a strong software engineering foundation and a track record of building reliable backend systems. You are comfortable working across application logic, APIs, databases, data processing, and system architecture, and you understand what it takes to operate software successfully in production.

You enjoy hands‑on development but can also step back and consider the broader architecture. You can make pragmatic technical decisions, explain trade‑offs, improve existing systems, and help other developers grow.

Experience with data engineering and AI‑enabled applications is highly valuable, but deep Python and backend engineering expertise is the foundation of this role.