Base
Budapest, Hungary
whoami / professional profile
Mihaly Kertesz
I solve enterprise data problems where the cost of failure is high.
Database engineering, SQL Server review work, product building, security thinking, and enough operations history to distrust easy answers.
20+ years in enterprise databases and infrastructurebanking, logistics, and large enterprise environmentsmulti-platform certified: Oracle, IBM, Red Hatsecurity, HA, backup/recovery, tuning, product, SEO
Now
Passary + selected high-impact SQL Server work
Availability
Booking roughly 2 weeks out
Language
Hungarian - native / English - full professional proficiency
Timezone
Budapest / strong fit for Europe-UK, useful overnight overlap for US
Summary
I solve enterprise data problems where failure is expensive. The main ground has been banking, logistics, and other larger environments where bad changes, weak recovery, or unstable systems have financial and operational consequences.
I am multi-platform certified across Oracle, IBM, and Red Hat. The point is not collecting badges. It is being able to read the whole environment instead of staring at one database setting.
Building Passary is not separate from database work. It is the same bias toward security, ownership, architecture, and risk control applied to a product.
I keep consulting deliberately narrow. I take on a limited number of active SQL Server engagements so the work stays focused on the client environment instead of getting buried under too many tickets.
Focus areas
Databases and operations
High availability, backup and recovery, performance tuning, operational discipline, resilient systems.
Security and ownership
Encryption, minimal attack surface, local data ownership, and a zero-cloud mindset where it makes sense.
Product work
Passary, zero-trust thinking, ownership-first architecture, and practical product decisions that have to hold up in real use.
SEO and web
Technical SEO, content and site building through BPSEO, plus web projects when needed.
Experience
Roles, projects, and direction.
Dec 2025 - Present
Budapest / remote / part-time
Passary
Founder
Building and steering an offline password manager. The work uses the same paranoia and precision I bring to enterprise databases: zero-trust architecture, high-availability data ownership, and operational stability.
Jun 2025 - Dec 2025
remote / specialized engineering project
Transcom
Database Engineer / Specialized Engineering Project
A short but intense enterprise database role where stability and operable solutions mattered most.
Dec 2019 - May 2025
Budapest / remote / independent advisory
BPSEO
Independent Engineering
Independent technical work across SEO, websites, and content systems. Useful here because it added product, commercial, and decision-making depth without pulling me away from infrastructure work.
Apr 2024 - Dec 2024
Budapest / hybrid / full-time
KBC Global Services
Senior Database Engineer
Enterprise database work, operations, and reliability in a banking environment.
Apr 2022 - Feb 2024
Budapest
Hellmann Worldwide Logistics
Database Engineer
Database work for logistics systems, with a focus on performance, stability, and failure handling.
Nov 2017 - Apr 2022
enterprise
Unisys
Senior Database Engineer
A longer enterprise database period with a strong focus on operations and reliability.
Jan 2016 - Nov 2017
enterprise
Oracle
Database Engineer
Oracle-heavy work, operations, performance, and a practical systems mindset.
Oct 2015 - Jan 2016
banking
Erste Bank
Database Administrator
Database work in a banking environment, where production systems had to be treated seriously.
Oct 2013 - Oct 2014
London Area, United Kingdom
Advanced365
Database Administrator
UK-based database work, useful for building practical delivery habits outside a single-platform bubble.
Apr 2012 - Oct 2013
Brno, South Moravia, Czechia
IBM
Database Administrator
Infrastructure and database support work in a larger enterprise setting, with the usual mix of tickets, incidents, process, and careful changes.
2010 - 2011
enterprise
HPE
Database Administrator
Enterprise operations and support work where process, reliability, and clean handover mattered as much as the technical fix.
2007 - 2008
enterprise
IT Services Hungary Kft.
Database Administrator
Early database administration work in a larger delivery environment, where documentation, escalation paths, and repeatable fixes were part of the job.