Senior Backend Software Engineer (Python / AWS)

About the company

About Darize There are projects that maintain a business. There are also those that change and grow it. If you are closer to the latter option – we have a lot in common. At Darize, we collaborate with organizations facing complex technological challenges.

In the IT world, it is a well-known scenario: before one project reaches its end, you already have to think about the next one. Added to this is uncertainty, discussions about rates, and formal matters that can effectively distract attention from what is truly important. That is why we want to be more than just a project provider. We care about the stability of cooperation, ensure access to ambitious technological initiatives, and create a community of experienced experts, thanks to which you can focus on what you do best.

Darize brings together over 2500 consultants in 24 countries. In Poland, you may associate us with the 7N brand, under which we operated for over 20 years. We focus on experience, long-term relationships, and a culture based on trust, quality, and Scandinavian values. We have the courage to question the status quo and create an environment where people are more important than processes, while delivering breakthrough technological solutions.

Your tasks

• Designing and developing backend services based on serverless and event-driven architecture in AWS.
• Analyzing existing AWS architecture and improving it in terms of cost, performance, scalability, and fault tolerance.
• Utilizing the AWS Well-Architected Framework when planning and implementing improvements.
• Optimizing event stream processing in terms of throughput, latency, ordering, and retry mechanisms.
• Designing reliable DLQ, replay, and idempotent event processing mechanisms.
• Optimizing PostgreSQL, including data models, queries, indexes, partitioning, and resource utilization.
• Developing observability through metrics, tracing, and alerting.
• Defining SLOs for mission-critical services.
• Ensuring code quality through unit, integration, and performance tests.

Requirements

We are looking for a Senior Back-end Software Engineer with strong experience in the area of AWS, backend systems, and data processing solutions. The role focuses on serverless and event-driven architecture, performance and scalability optimization, as well as PostgreSQL. We are looking for someone who can independently make technical decisions and freely discuss architectural trade-offs.

• Minimum 5 years of experience in backend development in Python or Scala.
• Minimum 5 years of practical experience with AWS, particularly with services such as Lambda, API Gateway, SQS, SNS, EventBridge, EventBridge Pipes, DynamoDB, and S3.
• Practical experience with relational databases, especially PostgreSQL.
• Knowledge of NoSQL databases, e.g., DynamoDB, including data modeling and creating efficient queries.
• Experience in designing and implementing RESTful API.
• Software engineering best practices, including unit and integration tests, code review, and Git.
• Experience with Infrastructure as Code using CloudFormation.
• Interest in technology and architecture, and openness to analyzing different ways to solve a problem.
• Ability to work independently and collaborate effectively in a team.
• Very good knowledge of English in speaking and writing.
• A big plus will be previous experience with Scala. Alternatively, experience with Kotlin or Java will be valuable.
• We will appreciate knowledge of observability tools such as CloudWatch or X-Ray.
• An additional asset will be knowledge of HL IT products or the container transport industry.

Must have: DevOps, Kubernetes, Go, Python, Terraform, Pulumi, LLM

What we offer

• Constant support from a personal agent (mentor), who takes care of your project continuity, client contact, necessary formalities, cooperation comfort, and development
• Access to Darize Learning & Development – a development and educational platform with webinars, a library of articles and industry reports, additional platforms (including DataCamp and Coursera), and regular invitations to development events – technical, business, and lifestyle
• Consultant Development Program - advice on planning professional development based on current trends and market needs, implemented by experienced mentors and development guardians
• A benefit package planned from A to Z, including subsidies for medical care, life insurance, a sports card for you and your loved ones, as well as discounts at stores in Poland and abroad
• A community of experienced IT experts and the opportunity to exchange knowledge with practitioners having many years of experience in implementing technological projects (the average professional seniority of consultants in Poland is over 10 years)

Other

*Work mode: remote Duration: 12 months Start date**: 01.11.2026