Data Science Tech Lead: Hands-On, Mentoring & Delivery

Sii Poland; Poznań; On-site; PLN 240,000 - 360,000; Full time

Benefits offered by this job

Great Place to Work

Solid financial situation

Contracts with the biggest brands

Centre of internal trainings

Many experts you can learn from

Open and accessible management team

Profit sharing

Passion Sponsorship program

Regular integration events and trips

Comfortable and well-equipped offices

MySii app

Medical care

Job summary

Sii Poland is seeking a technical lead in Poznań to drive end-to-end data science engagements. You will own problem framing, modeling decisions, and delivery quality while mentoring a team of data scientists and managing client expectations.

You'll stay hands-on with Python and review complex models, set engineering standards, and guide platform choices across multiple cloud/data ecosystems. Fluent English and Polish are required to collaborate with global clients.

Qualifications

• 6+ years in data science with models shipped to production.
• 2+ years leading or mentoring data scientists.
• Strong statistical and ML foundations: experimental design and validation.
• Fluent English and Polish; residing in Poland.

Responsibilities

• Own the technical direction of data science engagements: solution design, modeling approach, validation strategy, and delivery quality.
• Lead and mentor a team of data scientists: code reviews, methodology reviews, career development, and raising the bar on what "done" means.
• Hands-on prototyping: develop approaches and contribute production-grade Python where it matters.
• Translate client problems into scoped, estimable data science workstreams and push back when a model isn't needed.
• Set and enforce engineering standards: reproducibility, experiment tracking, testing, documentation.
• Guide platform decisions across cloud/data ecosystems: Fabric, Foundry, Databricks, Snowflake, Azure/AWS/GCP.
• Collaborate with AI Architects, data engineers, and client stakeholders to align decisions with business outcomes.
• Represent the team in front of clients: present results and defend methodology.

Skills

Data science

Python

Team leadership

Client-facing

ML & statistics

Cloud platforms

English (Fluent)

Polish (Fluent)

Tools

Databricks

Microsoft Fabric

Palantir Foundry

Azure

AWS

GCP

Job description

Sii Poland is seeking a technical lead in Poznań to drive end-to-end data science engagements. You will own problem framing, modeling decisions, and delivery quality while mentoring a team of data scientists and managing client expectations.

You'll stay hands-on with Python and review complex models, set engineering standards, and guide platform choices across multiple cloud/data ecosystems. Fluent English and Polish are required to collaborate with global clients.