Junior Big Data Engineer (Java / Python)

About the role:

Important things for you:

• Flexible working hours in the hybrid model (4/1) - working hours start between 7:00 a.m. and 10:00 a.m. We also have 30 days of occasional remote work.
• The salary range for this position depending on the skill set is as follows (contract of employment, tax-deductible cost):
• Junior Big Data Engineer: 11 200 - 15 250 PLN
• Annual bonus based on your annual performance and company results.

We are looking for a Junior Big Data Engineer to learn how to build and operate the foundations that make data reliable, discoverable, governed, and usable at scale across Allegro.

You will work with experienced engineers on production data-platform services and pipelines. Our products include event ingestion into BigQuery, schema contracts and evolution, data quality and freshness SLAs, data governance and GDPR-related data lifecycle processes, and metadata capabilities. This role is designed for engineers who want to grow beyond business reporting and analytical transformations into software engineering for shared, enterprise-scale data-platform products.

This is the right job for you if you:

• Have commercial experience in Python, Java or Kotlin.
• Demonstrate basic ability to write clean, tested code and an eagerness to learn modern software engineering practices.
• Possess solid SQL fundamentals.
• Have a basic understanding of data modeling, relational databases, APIs, and common data formats (e.g., JSON, CSV, Avro, Parquet).
• Are interested in cloud platforms, distributed systems, and data processing at scale.
• Can diagnose problems systematically, ask good questions, and learn actively from feedback.
• Speak English at a B2 level or higher.

In your daily work you will handle the following tasks:

• Developing, testing, and maintaining parts of production data pipelines, services, and internal tooling with support from the team.
• Learning to work with BigQuery, Cloud Composer (Airflow), GCS, and other Google Cloud Platform services.
• Helping implement data ingestion, validation, data-quality checks, monitoring, alerts, and operational automation.
• Working with structured, semi-structured, and event data using formats such as Avro, Protobuf, Parquet, JSON, and CSV.
• Participating in code reviews, technical discussions, incident follow-ups, and documentation.
• Collaborating with engineers, analysts, and product stakeholders to understand how data products are used.

Technologies you will work with:

• Python, Java, Kotlin, Spring Framework, Git.
• Google Cloud Platform: BigQuery, Cloud Composer (Airflow), Cloud Run, GCS, Dataflow.
• PostgreSQL, Neo4j.
• Data formats: Avro, Protobuf, Parquet, JSON, CSV.

Nice to have:

• Personal, academic, or commercial projects involving data pipelines, backend services, cloud platforms, or SQL data warehouses.
• Familiarity with Docker, Git, CI/CD, Linux, or cloud infrastructure fundamentals.
• Exposure to DBT, Airflow, Apache Beam, Spark, Kafka, or streaming systems.

What's in it for you:

• Flexible working hours in the hybrid model (4/1) - working hours start between 7:00 a.m. and 10:00 a.m. We also have 30 days of occasional remote work.
• Well-located offices (with e.g. fully equipped kitchens, bicycle parking, terraces full of greenery) and excellent work tools (e.g., raised desks, ergonomic chairs, interactive conference rooms).
• A 16" or 14" MacBook Pro or corresponding Dell with Windows (if you don't like Macs) and all the necessary accessories.
• A wide selection of fringe benefits in a cafeteria plan - you choose what you like (e.g., medical, sports or lunch packages, insurance, purchase vouchers).
• English classes that we pay for related to the specific nature of your job.
• A training budget, inter-team tourism (see more here), hackathons, and an internal learning platform where you will find multiple trainings.
• An additional day off for volunteering, which you can use alone, with a team, or with a larger group of people connected by a common goal.
• Social events for Allegro people - Spin Kilometers, Family Day, Fat Thursday, Advent of Code, and many other occasions we enjoy.

And that's just the beginning! You can read more about the benefits here.

#goodtobehere means that:

• You will join a team you can count on - we work with top-class specialists who have knowledge- and experience-sharing in their DNA.
• You will love our level of autonomy in team organization, the space for continuous development, and the opportunity to try new things. You get to choose which technology solves the problem and you are responsible for what you create.
• You will value our Developer Experience and the full platform of tools and technologies that make creating software easier. We rely on an internal ecosystem based on self-service and widely used tools such as Kubernetes, Docker, Consul, GitHub, and GitHub Actions. Thanks to this, you can contribute to Allegro from your very first days on the job.
• You will be equipped with modern AI tools to automate repetitive tasks, allowing you to focus on developing new services and refining existing ones (also leveraging AI support).
• You will create solutions that will be used (and loved!) by your friends, family and millions of our customers.
• You will meet the Allegro Scale, which starts with over 1000 microservices, an open-source data bus (Hermes) with 300K+ rps, a Service Mesh with 1M+ rps, tens of petabytes of data, and production-used machine learning.
• You will become part of Allegro Tech - We speak at industry conferences, cooperate with tech communities, run our own blog (it's been over 10 years!), record podcasts, lead guilds, and we organize our own internal conference - the Allegro Tech Meeting. We create solutions we love (and can) to talk about!

Send us your CV and... see you at Allegro!