Senior Database Administrator (D8536D2)

Referment; Warszawa; Hybrid; PLN 180,000 - 240,000; Full time

Benefits offered by this job

Equity participation

Private healthcare

Wellbeing stipend

Job summary

Referment is expanding its finance-technology platform and seeks a Senior Database Administrator in Warsaw. You will own database reliability across production systems, optimizing performance, backups, and capacity while collaborating with engineering squads on schema and query design.

You will drive migrations to PostgreSQL when needed, maintain data integrity, and champion robust incident response in a banking-focused environment with on-premises constraints.

Qualifications

• Deep, production-tested MSSQL administration expertise including performance tuning, backup and disaster recovery.
• Ownership mindset with responsibility for database outcomes in production environments.
• Ability to connect technical decisions to business consequences for bank clients.

Responsibilities

• Own database reliability across production systems including performance, availability, backup and capacity planning.
• Lead migrations and version upgrades, including moves from MSSQL to PostgreSQL where appropriate.
• Review schema changes and queries to maintain engineering standards and reliability.

Skills

MSSQL administration

Performance tuning

Ownership mindset

Business impact awareness

On-premises banking environments

AI-assisted tooling

Tools

PostgreSQL

ClickHouse

Azure

Kubernetes

Terraform

Kafka

Job description

Referment is working with a financial technology business whose software gives banks the data intelligence behind personalised digital banking. Its systems operate inside live bank environments, where database performance, availability and data integrity have direct consequences for clients.

The platform is undergoing a transformation across performance, architecture and AI. Alongside that work, the database strategy is moving from MSSQL alone towards a broader stack that includes PostgreSQL and analytical databases such as ClickHouse. As a Senior Database Administrator, you'll help keep that changing landscape fast, secure and dependable.

You'll join the Platform Team and work alongside other DBAs with expertise across MSSQL and additional databases. This is an ownership role: you'll contribute to design decisions with engineering squads, take responsibility for production health and drive mitigation when something goes wrong, rather than operate only as a ticket queue.

The Role

• Own database reliability across production systems, covering performance, availability, backup and recovery, and capacity planning within bank client environments.
• Work with engineering squads on schema and query design, contributing early to architecture discussions rather than reviewing decisions only after implementation.
• Lead performance tuning and troubleshooting on database-heavy systems. Diagnose slow queries, indexing problems and other issues under real production load, with an understanding of the client consequences.
• Own database migrations and version upgrades, including moves from MSSQL to PostgreSQL where appropriate.
• Review schema changes and queries to maintain engineering standards. Challenge shortcuts that could compromise reliability or data integrity and help teams deliver sound alternatives.
• Maintain accountability from design through production, taking an active role in resolving incidents and improving the health of the data layer.

What We're Looking For

• Deep, production-tested MSSQL administration expertise, including performance tuning, indexing strategy, backup and disaster recovery, security and troubleshooting under real load.
• A practical ownership mindset: you take responsibility for database outcomes, not just the completion of activities, and drive mitigation when problems arise.
• The ability to connect technical decisions to business consequences. You'll work with engineering squads as a partner and understand what database failures or poor performance mean for bank clients.
• Comfort delivering within constrained, often locked-down on-premises banking environments. The work requires finding workable solutions without assuming a clean-slate infrastructure.
• Regular use of AI-assisted tools such as Cursor and Claude Code as part of your engineering workflow.

Relevant Desirable Experience

• PostgreSQL and ClickHouse are particularly valuable as the platform's database stack expands.
• Azure, Kubernetes and Terraform.
• Kafka and ETL workflows.
• Fintech or a comparable environment with demanding production and client requirements.

Working Environment

This is a B2B contract engagement with two office days and three remote days each week. The source lists equity participation, private healthcare and support for wellbeing and everyday working costs. You'll work in a team that welcomes technical opinions and on software deployed within large banks.

Interview Process

A 30-minute screening call explores real systems, decisions and trade-offs. A 15-minute discussion with the CTO focuses on how you think and what matters to you technically. The technical interview lasts 90 minutes, either on-site or by call, and combines a real performance or design problem with troubleshooting, AI and a conversation with a senior colleague. AI tools are welcome.

This could suit a senior SQL Server DBA who combines strong production judgement with collaborative engineering habits and wants to contribute to database modernisation without stepping away from operational ownership.

#Referment