Data Engineer for B2B go-to-market software

Bain's Next Generation Software Solutions team builds, scales, supports, and maintains software products that enable Bain's intellectual property and consulting solutions. Coro is Bain's proprietary B2B go-to-market software suite, delivering AI-accelerated data, analytics, and GTM tools that help revenue organizations identify opportunities, align commercial teams, and drive profitable growth at scale.

• Design, build, and maintain batch and streaming pipelines in Python, including orchestration, scheduling, and monitoring;
• Write reusable, well-typed Python libraries and internal packages for engineers and analysts;
• Build Python services and APIs that expose data to downstream applications and integrate with third-party and internal APIs;
• Write unit, integration, and data-contract tests and maintain automated CI coverage for pipelines;
• Profile and optimize Python code and data-processing jobs for runtime, memory, and cost;
• Deploy and operate code in the cloud using containers, infrastructure as code, and CI/CD;
• Enforce access controls, secrets handling, and sensitive-data protections throughout the data lifecycle;
• Find and fix efficiency, reliability, cost, and correctness problems in existing code and pipelines;
• Refactor code and pipelines toward simpler designs;
• Replace one-off scripts and notebooks with tested, packaged, scheduled code;
• Implement data quality checks, validation, and monitoring that identify issues before consumers do.

• 2–4+ Years of experience shipping production Python, building and operating ETL/ELT pipelines at scale, and using Python data tooling;
• Experience with pandas, Polars, PyArrow, DuckDB, or PySpark;
• Experience with schema enforcement and validation using Pydantic or similar tools;
• Experience with workflow orchestration in code using Airflow, Dagster, Prefect, dbt, or Temporal;
• Experience with testing and quality tooling such as pytest, pyright, ty, pyrefly, ruff, or black;
• Experience with dependency and environment management using uv, Poetry, pip-tools, or conda;
• Experience with at least one public cloud, including its Python SDK, and familiarity with AWS, Azure, or GCP;
• Experience with Snowflake, Databricks, BigQuery, or Redshift;
• Experience with relational and non-relational databases, including schema design;
• Bachelor's degree or an equivalent combination of education, training, and experience;
• Strong, idiomatic Python, including data structures, typing, error handling, generators/iterators, context managers, and the standard library;
• Knowledge of modular design, dependency management, packaging, semantic versioning, and API design;
• Testing discipline, including pytest, fixtures, mocking, and writing testable code;
• Ability to debug and profile code and reason about performance, concurrency, and memory in Python;
• Working knowledge of SQL, data modeling, governance, and privacy practices sufficient to design sound schemas and query them effectively;
• Ability to explain technical trade-offs to technical and business audiences;
• Nice to have: Python web/API frameworks such as FastAPI or Flask, async Python, multiprocessing or other concurrency patterns, Kafka, Kinesis or Spark Structured Streaming, Terraform, GitHub Actions, Docker, Kubernetes, Go, Rust, Scala or TypeScript, generative AI, machine learning or data science tooling.

• Office role in Warsaw, Mazowieckie, Poland;
• CVs must be submitted in English to be considered.