Senior Backend Developer

PeopleForce; Polska; Remote; PLN 306,000 - 481,000; Part time

Benefits offered by this job

Remote work in EU time zones

Competitive B2B contract

Growth opportunities in a fast-paced #

Impactful projects in ETF data

Innovation culture

European team events

Job summary

ETFBOOK is a Swiss SaaS company delivering data analytics and APIs for ETFs, with a fully remote Europe-wide team and monthly visits to Cracow. We seek a Senior Backend Software Developer to strengthen our backend platform and data-processing components, driving scalable, secure solutions.

You will design architectures, develop .NET services, and mentor junior engineers while collaborating with Product, Data, and Technology teams to deliver high-quality outcomes.

Qualifications

• 8+ years in software development with strong .NET/C#.
• Backend services, APIs and data processing experience.
• Strong architecture and database design knowledge.
• SQL skills and DB optimization experience.
• Scalable, secure, reliable backend solutions.
• Automated testing and deployment experience.
• Experience with AI-assisted development tools.
• Good knowledge of Azure.
• Strong English communication.
• Mentoring junior/mid-level engineers and code review.

Responsibilities

• Design and optimize application architecture and database schemas.
• Develop and maintain .NET services, APIs, and data-processing components.
• Participate in solution design and requirements analysis for major initiatives.
• Ensure backend performance, security, and reliability.
• Review backend code and promote engineering standards.
• Troubleshoot complex production and system issues.
• Mentor junior and mid-level backend engineers.

Skills

.NET/C# expertise

APIs

Backend design

SQL & DB optimization

Azure

Automated testing

CI/CD

AI-assisted tooling

English communication

Mentoring juniors

Code review

Security & reliability

Job description

Senior Backend Developer

Location: Remote (European Time Zone), once per month in the office in Cracow

Contract Type: B2B

About Us

ETFBOOK is a Swiss SaaS company providing data, analytics, and custom solutions in the Exchange Traded Funds (ETFs) space. Founded in 2020, we aim to make global ETF data accessible, actionable, and valuable for institutional participants, including ETF issuers, index providers, fund service providers, market makers, exchanges, and buy-side institutions.

We develop a platform which offers comprehensive insights through a user-friendly web application and robust APIs, covering areas such as product analysis, fund flow tracking, performance comparisons, and liquidity assessments.

About the role

We are seeking a Senior Backend Software Developer to join our fully remote team spread across Europe. You’ll join a highly skilled technology team. This team develops and maintains a cutting-edge data analytics platform using most advanced technologies to support all core business functions. You’ll be a part of a collaborative team focused on application development. This role offers the chance to make a visible impact in a dynamic, fast-evolving field.

Responsibilities

• Designs and optimizes application architecture and database schemas.
• Develops and maintains the latest .NET services, APIs, and data-processing components.
• Participates in solution design and requirements analysis for major initiatives.
• Ensures backend performance, scalability, security, and reliability.
• Reviews backend code and promotes engineering standards.
• Troubleshoots complex production and system issues.
• Mentors junior and mid-level backend engineers.

Requirements

• 8+ years of experience in software development with strong experience in the latest .NET/ C#.
• Strong expertise in backend services, APIs and data processing.
• Strong understanding of application architecture and database design.
• Strong SQL skills and experience with database optimization.
• Experience designing scalable, secure and reliable backend solutions.
• Experience with automated testing and deployment.
• Experience with AI-assisted development tools.
• Good knowledge of Azure
• Strong communication skills in English.
• Strong problem-solving skills.
• Able to work effectively with Product, Data and Technology teams.
• Able to review code and provide technical guidance.
• Able to mentor Junior and Mid-level engineers.
• Commitment to delivering high-quality solutions.

Nice to have

• Experience with data visualization.
• Interest in financial markets, especially ETFs.
• Experience with B2B SaaS products

What we offer

• 100% remote work from anywhere within the European time zone.
• Competitive B2B contract.
• Exciting growth opportunities in a fast-paced startup.
• Impactful work: help revolutionise ETF data market, currently fastest growing area of finance.
• Have a real impact of developing products: your work will directly influence live projects, delivering measurable results in real-world applications.
• Culture of innovation: collaborate with forward-thinking professionals in technology and finance where experimentation and creativity are encouraged.
• Team- buildings events at least twice a year, hosted in various European locations.