Volia Software

About The Role

We are looking for a Senior Python Optimization Engineer / Gurobi Modeler to support a Python-based Unit Commitment model that uses Gurobi as a MILP solver.  

This is expected to be a long-term, part-time engagement with regular overlap with US Eastern Time. The role will help maintain, troubleshoot, and extend the existing model as it becomes part of a standard customer offering. Workload may vary over time, with occasional ramp-up during customer implementations and lighter ongoing support between projects.

The ideal candidate combines strong Python engineering, practical MILP modeling experience, and hands-on Gurobi knowledge. Experience in power systems, energy markets, or Unit Commitment is strongly preferred.

Key Responsibilities

• Maintain and enhance an existing Python-based Unit Commitment optimization model.
• Troubleshoot model behavior, infeasibility issues, solver performance, and customer-specific cases.
• Extend the model with new constraints, business rules, objective terms, or configuration options.
• Provide ongoing part-time support for issues that arise between implementation projects.
• Improve model maintainability, structure, documentation, and repeatability.
• Work with client-side product teams and engineering stakeholders to clarify requirements and validate results.
• Document model assumptions, formulation logic, known limitations, changes, and troubleshooting steps.

Technical Requirements

Required:

• Strong Python development experience.
• Hands-on experience with Gurobi.
• Practical experience building, maintaining, or extending MILP optimization models.
• Ability to debug optimization models, including infeasibility, constraint behavior, and solver performance issues.
• Experience working with existing codebases and improving model maintainability.
• Ability to understand mathematical formulations and translate them into production-quality Python code.
• Strong analytical and problem-solving skills.
• Good written and spoken English communication.
• Reliable availability for a part-time engagement.
• Regular working-hours overlap with US Eastern Time.

Nice To Have:

• Experience with Unit Commitment models.
• Experience in power systems, electricity markets, energy optimization, or production cost modeling.
• Familiarity with economic dispatch, reserves, ramping constraints, startup/shutdown logic, min up/down times, renewables, storage, or transmission constraints.
• Experience with pandas, NumPy, or similar Python optimization/data libraries.
• Experience tuning Gurobi models for performance.
• Experience productizing analytical or optimization models for repeat customer use.
• Experience supporting customer implementations or production troubleshooting.
• Ability to explain model behavior and tradeoffs to both technical and non-technical stakeholders.

As a leading SaaS provider, the company delivers comprehensive supply chain management solutions aimed at enhancing transparency, sustainability, and responsible sourcing practices. Our commitment to innovation and excellence drives us to effect positive change across global supply chains.

Position Overview:
We are looking for a Senior DevOps engineer, located in Poland (100% remote). This role is ideal for someone who thrives in maintaining scalable, high-quality applications and possesses strong English communication skills. A crucial aspect of this position is the ability to work within cross-functional squads, collaborating closely with team members across various disciplines to deliver innovative services.

Key Responsibilities:

• Support application infrastructure to ensure platform is optimized for performance and reliability.
• Build and maintain supporting infrastructure for cloud environments and applications.
• Use a wide range of Azure resources to implement scalable, reliable and cost-efficient services.
• Work side by side with your engineers, guiding critical projects, using your subject matter expertise to solve complex problems.
• Perform and automate system administration services including installation, configuration, maintenance, and disaster recovery
• Identify system level issues related to OS configuration and virtual hardware bottlenecks.
• Automation, auditing, and other tooling for security, compliance, and resource usage - Monitor and improve processes for all deployments.
• Take ownership of operational excellence to establish and maintain business focused KPI’s. Use these metrics not only as a basis for positive transformation, but also as a visible representation of your team’s success.
• Maintain and take ownership of your tasks each sprint ensuring time worked is logged and details are added.

Skills required:

• Excellent communication and collaboration skills.
• Ability to communicate effectively with multiple disciplines.
• Strong analytical skills with the ability to drive reliability improvements.
• Proven success managing and optimizing CI/CD for an Azure-based SaaS application.
• Hands-on-experience with common DevOps tools, including Azure DevOps.
• Strong scripting skills with at least PowerShell or Bash.
• Experience with configuration management tools like Terraform.
• Working knowledge of version control/source code management tools.
• Experience working in an agile software development life cycle.
• Working knowledge of databases including SQL and NoSQL
• Strong knowledge of web server configuration and management like IIS or Tomcat.
• Working knowledge of local and wide area networking and associated technologies, e.g. switches, routers, firewalls, VPNs.
• Strong understanding of security principles.
• Bachelor’s Degree in Computer Science or similar area of study.
• Experience working in a technical fast paced environment with high demand and high standards.
• Ability to assimilate information quickly under pressure.
• Strong planning skills to ensure business expectations are met and projects are delivered on time.

Experience required:

• Cloud-based networking (VNETs, NSGs, Route Tables, Hub/Spoke based architecture, Private Endpoints, etc)
• Strong understanding of CI/CD (YAML and Classic Pipelines)
• PaaS (Web Apps, Function Apps, Storage Accounts, Key Vaults, Azure Redis Cache, Azure Service Bus, API Management, Azure Data Factory, Azure Databricks)
• Monitoring (New Relic, LogEntries, Rapid7, Azure Monitoring, etc)
• Some experience with Containers/Docker either for a microservice based architecture or Service Orientated etc
• Git, ARM, Terraform, Ansible, Azure CLI or similar.
• JavaScript, React, C#, Java, PowerShell, Bash or similar.

Work conditions:

• Distributed team: REMOTE work (Poland located candidates only).
• 2-weeks scrum, 5-8 team members / team.
• Full-time (40 hours per week).
• Official contract: salary, sick-leave days, holidays, vacations.

Hiring process:
Step 1 - preliminary interview (main questions) - 30 mins
Step 2 - cultural fit interview with principal engineer - 45-60 mins
Step 3 - tech interview with team leader - 1 hr
Step 4 - final interview with PMO - 45-60 mins