Data & AI Consultant · Prague

Helping companies
become truly data-driven

Consultant and data strategist with 15+ years of experience across E.ON, Avast and ING Bank. I help companies define data strategy, build modern data platforms and create a culture where data genuinely drives decisions.

DJ
David Jež, MBA
Data strategy · Platform · AI enablement
🏗️
Data Platform & Engineering
🧭
Data Strategy & Governance
🤖
AI Enablement
👥
Leadership & Transformation
📊
BI & Analytics
🔒
Data Privacy & Security
Companies
E.ONAvastING Bank
How I can help
Data & AI for your organisation

I work with companies that want to turn data into a real competitive advantage — not just better reporting. I help define data strategy, select and build the right platform, establish governance and create a culture where data genuinely informs decisions at every level.

I bring 15+ years of hands-on experience spanning every data role — from analyst and architect to CDO — at organisations such as E.ON, Avast and ING Bank. I understand both sides of the equation: technical reality and strategic ambition. That lets me bridge the gap between IT and leadership and help organisations move forward without unnecessary detours.

Whether you're tackling data strategy, migrating to a modern cloud platform, rolling out AI across the business or transforming your data team — let's talk.

I also run hands-on training sessions and workshops on AI adoption, SQL and data analysis for teams at all skill levels.

Data strategy & roadmap
Cloud data platform
AI enablement & adoption
Data governance & quality
Data team transformation
BI & management analytics
Training & workshops
Training & Workshops
Building data & AI skills

Alongside strategic advisory, I design and facilitate workshops tailored to your team's needs. Whether you want to upskill your analysts, build AI fluency across the organisation or help business teams become more confident with data — the topics below are where I can help.

🤖

AI for Business

Practical AI adoption workshop for teams and executives. Focused on real tools, real use cases and building genuine AI habits — not just awareness.

How modern AI tools work
Practical prompting & workflows
AI use cases by role & function
Copilot, ChatGPT, Claude in practice
AI safety and responsible use
🗄️

SQL & Data Analysis

Hands-on training covering SQL from the ground up through to analytical querying. Designed for business analysts, finance teams and anyone who works with data daily.

SQL fundamentals & querying
Joins, aggregations, window functions
Working with real business datasets
Data analysis patterns & best practices
From query to insight
📊

Data Literacy for Teams

Building a data-literate organisation from the inside out. Tailored for non-technical teams who need to read, question and use data confidently in their daily work.

Reading and interpreting dashboards
Understanding metrics & KPIs
Data quality and critical thinking
Self-service analytics with Power BI
Asking better questions of data
Expertise
What I bring

My work spans the full data and AI spectrum — from hands-on platform architecture to organisational strategy and team leadership. These are the core areas where I can add the most value.

🏗️

Data Platform & Engineering

Databricks, Azure, Delta Lake, Medallion architecture, Unity Catalog. From architecture design through delivery and operations.

🧭

Data Strategy & Governance

Strategy aligned with business domains, ownership model, Data Catalog, data quality standards and MDM.

🤖

AI Enablement

Embedding AI into business processes, building AI literacy across the organisation, ML use cases and AI-driven decision making.

👥

Leadership & Transformation

Building and leading data teams, agile transformation to a product model, OKR framework, servant leadership.

📊

Business Intelligence

End-to-end BI solutions, Power BI, KPI reporting for management and board level. Self-service analytics.

🔒

Data Privacy & Security

GDPR compliance, RBAC models for DWH and Data Lake, data masking, access control, retention policies.

Projects
Selected work

A selection of projects that reflect the depth and breadth of my experience — from enterprise platform architecture and organisational design to data governance, compliance and reporting. Each represents a meaningful initiative with real business impact.

ArchitectureE.ON
E.ON Czech Republic · 2025–2026

Enterprise Data Platform (EDP)

Architecture and delivery of a modern data platform on Databricks & Azure — Medallion architecture, Unity Catalog, Delta Lake. The backbone of all data and AI activity across the company.

StrategyE.ON
E.ON Czech Republic · 2025–2026

Data & AI Tribe Design

Design and implementation of the Data & AI Tribe as a product organisation — product team structure, OKR framework, seniority model and ways of working aligned with agile principles.

ArchitectureAvast
Avast · 2019–2022

Customer 360 Architecture & Development

Architecture and development of a Customer 360 platform — unifying customer data from disparate systems into a single source of truth for analytics and personalisation at global scale.

ArchitectureAvast
Avast · 2015–2022

Enterprise DWH Design & Architecture

Owner and lead of the global Enterprise Data Warehouse. Design, management and maintenance — successful migration from MS SQL to Greenplum (90 databases, 4 TB of data, 10 business-critical projects).

ComplianceAvast
Avast · 2018

GDPR Compliance Data Integration

Integration of customer PII data onto a unified platform to handle GDPR requests. ETL pipeline development and connection to the company's public GDPR portal.

ReportingAvast
Avast · 2017–2019

KPI Data Model & Board Reporting

KPI reporting for top management and stock exchange disclosure. Full database layer, ETL automation and custom orchestration. Outputs served as the basis for strategic leadership decisions.

SecurityAvast
Avast · 2019

Data Security Measures Design

Introduction of an RBAC model for DWH and Data Lake access control. Definition of data masking procedures, PII anonymisation, data retention policy and security standards.

MDMAvast
Avast · 2016–2018

MDM/RDM Design & Implementation

Design and implementation of a Master Data Management solution — defining master data domains, data quality management, data profiling, acquisition and merging processes.

Career
Work experience

Over 15 years across energy, cybersecurity and banking — always at the intersection of data, technology and business. Each role has added a new layer: from hands-on engineering to architecture, management and C-level strategy.

09/2022 – present
Chief Data Officer
E.ON Czech Republic
  • Built and led a centralised Data Team covering Data Engineering, Analytics, Governance, and Reporting — operating as a unified Business + IT function. Currently driving the data transformation and the transition towards an agile, tribe-based organisational model.
  • Defined and executed the enterprise data strategy, including a multi-year roadmap aligned with business priorities across Finance, Customer, Energy Market, and Business domains.
  • Delivered multiple automation initiatives across Finance and business domains — including automated reporting pipelines, and establishing reporting governance standards and best practices for scalable, trusted reporting across the organisation.
  • Architected and delivered an Enterprise Data Platform on Databricks — successfully drove the business case for a full data landscape upgrade; platform architecture and core infrastructure delivered, legacy migration in progress.
  • Established a data governance framework including ownership model, data quality standards, and deployed governance tooling (Metadata Catalog & RDM).
  • Drove self-service analytics adoption through standardised tooling (Power BI, Databricks SQL), enabling non-technical stakeholders to access trusted data independently.
  • Led the company-wide data & AI literacy agenda — including executive workshops, AI enablement programmes, and internal capability building.
DatabricksAzureData GovernanceAI StrategyOKRAgile / Tribe
04/2019 – 09/2022
Data Engineering & Data Warehouse Manager
Avast (NortonLifeLock)
  • Led a team of data engineers (incl. project teams) responsible for the global Enterprise Data Warehouse platform — serving as the go-to data architecture authority across the organisation.
  • Designed and delivered the company's core data platform including architecture, ETL pipelines, data modelling, and automation of critical data flows.
  • Built and launched Customer 360 — a unified customer analytics solution that became the most widely adopted analytical tool in the company post-launch.
  • Acted as the key data lead for all major company-wide initiatives including IPO preparation, M&A integrations, and GDPR implementation (covering data governance, MDM, privacy controls, and security management) — ensuring data infrastructure and governance met the highest standards at every critical milestone.
DWHGreenplumCustomer 360GDPRIPO / M&ATeam Leadership
04/2015 – 03/2019
BI Principal & Data Warehouse Developer
Avast
  • Took full ownership of the company's Data Warehouse platform — responsible for architecture, development, and governance of the entire MS BI stack.
  • Delivered a unified Sales & Billing data model, consolidating highly fragmented data sources into a single reliable foundation — one of the most impactful data initiatives in the company at the time.
  • Built a web analytics data model integrating Google Analytics data into the DWH, enabling consistent reporting across digital channels.
  • Established development standards for the local Data Warehouse and led ETL development, data analysis, and automation of recurring reports.
  • Owned Master Data Management and contributed to forecasting and planning processes.
MS SQLSSIS / SSASMDMETLData Architecture
06/2013 – 04/2015
Junior Data Warehouse Specialist
ING Bank Prague
  • Designed and developed BI/DWH solutions on the Microsoft platform.
  • Built a reporting system to measure IT service delivery effectiveness.
  • Managed data quality and change management processes.
DWHETLReportingMS BI Stack
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