Senior Backend Developer – Core Gateway

About the role

payabl. is looking for a Senior Backend Developer to join its Core Gateway engineering team.

This is a dual-focus backend role combining the support of an existing payment gateway with the development of the company’s next-generation service architecture.

You will help maintain and extend a live Perl-based payment platform while designing and building modern backend services in Python. The systems you work on sit directly within critical payment flows, where reliability, scalability and performance are essential.

The role is suited to an experienced backend engineer who is comfortable working across legacy and modern technologies, understands the operational requirements of financial systems and can contribute to both technical architecture and product-focused decision-making.

The position reports to the Technical Lead.

What you’ll be doing

• Maintain and extend the existing Perl-based payment gateway.

• Investigate and resolve production issues affecting live transaction flows.

• Develop new functionality within the existing gateway while platform modernisation is underway.

• Design and build modern backend services using Python.

• Contribute to the migration from legacy systems towards a microservices-based architecture.

• Build services designed for high availability, scalability and reliable transaction processing.

• Integrate third-party APIs and external payment providers.

• Implement and maintain webhooks, callbacks and asynchronous integration flows.

• Design reliable retry and failure-handling strategies.

• Work with payment-processing business logic across both legacy and modern services.

• Collaborate with product, engineering and business stakeholders.

• Participate in agile development cycles and technical planning.

• Contribute to code reviews and maintain high engineering standards.

• Help improve code readability, maintainability and reliability.

• Work with DevOps teams on CI/CD, containerisation and cloud deployments.

• Contribute to event-driven architectures and message-based workflows.

• Take part in technical discussions around platform architecture and modernisation.

• Consider customer and business impact when designing technical solutions.

What we’re looking for

• At least five years of professional backend-engineering experience.

• Strong professional experience developing backend systems with Python.

• Experience with asynchronous Python development.

• Familiarity with AsyncIO and FastAPI is preferred.

• Experience working with Perl, or a genuine willingness to learn and maintain production Perl code.

• The ability to understand, refactor and improve legacy software.

• Strong experience integrating third-party APIs.

• Deep understanding of webhooks and callback-based integrations.

• Experience designing reliable retry policies and failure-handling mechanisms.

• Experience working with CI/CD pipelines.

• Familiarity with GitLab-based CI/CD workflows is preferred.

• Strong experience using Docker.

• Familiarity with AWS services and cloud infrastructure.

• Exposure to serverless technologies such as AWS Lambda.

• Understanding of event-driven architectures.

• Experience with Kafka, message queues or similar messaging systems.

• Strong understanding of clean-code and maintainable software-development practices.

• The ability to explain technical decisions and implementation choices clearly.

• Strong analytical and problem-solving skills.

• A product-focused mindset and interest in understanding the business impact of technical work.

• Strong written and spoken English.

• The ability to collaborate effectively across multidisciplinary teams.

Skills that would be an advantage

• Experience with payment gateways or payment-processing systems.

• Previous experience in fintech or financial services.

• Experience migrating legacy systems into modern service architectures.

• Deep knowledge of asynchronous and distributed systems.

• Experience designing high-availability production services.

• Familiarity with high-throughput transaction systems.

• Experience with message brokers and asynchronous processing.

• Knowledge of observability, monitoring and production reliability practices.

• Previous experience working with polyglot codebases.

• Experience contributing to platform-modernisation projects.

Engineering environment

This role combines two important areas of engineering work.

You will support a mature payment gateway that remains critical to day-to-day operations while helping build the modern services that will gradually replace parts of the existing platform.

The engineering culture places strong emphasis on clean code, technical reasoning and accountability. Developers are expected to understand why a solution works, not simply produce code that passes tests.

The team also values product awareness, meaning engineers are encouraged to understand how technical decisions affect customers, payment flows and the wider business.

Work arrangement

The position is available under the following arrangements:

• Cyprus – on-site employment arrangement.

• Poland – fully remote contractor arrangement.

Benefits and contractual conditions may differ depending on location.

Candidates should confirm working arrangements and contract conditions directly with payabl. during the recruitment process.

Benefits for Cyprus-based employees

Benefits available to employees based in Cyprus include:

• 25 days of annual leave.

• Cyprus public holidays.

• 10 days of sick leave.

• Provident Fund participation after successful completion of probation.

• Annual learning and professional-development budget after probation.

• €150 monthly Wolt allowance.

• Access to participating gyms and sports facilities.

• Complimentary office parking.

• Free Greek-language lessons twice per week.

• Employee discounts and access to selected entertainment and sporting events.

• Company-wide celebrations and international initiatives.

• Potential eligibility for a company car after one year, depending on performance and availability.

Benefits for Poland-based contractors may differ and should be confirmed during the recruitment process.

Recruitment process

The expected hiring process includes:

1. Talent Acquisition and technical screening – An initial conversation covering your experience, career background and motivation, together with a short technical assessment.

2. Practical technical assessment – A session with the Team Lead and technical specialists that may involve live coding or a realistic engineering scenario.

3. Final interview – A discussion with senior Technology leadership, potentially including the CTO, CPO and Team Lead, covering collaboration, expectations, team fit and the broader technology environment.

The exact stages may vary depending on the applicant and location.

About payabl.

payabl. is a financial-technology and payments company providing payment and banking services to businesses across international markets.

Its Core Gateway infrastructure supports critical payment-processing flows and integrations with external financial-services providers.

The company is continuing to modernise its technology platform by introducing scalable service-based architectures alongside its existing production systems.

How to apply

Applicants should submit an up-to-date CV through payabl.’s official careers page.

Your application should clearly demonstrate:

• Your professional backend-engineering experience.

• Your experience developing production systems with Python.

• Any work with FastAPI or AsyncIO.

• Your experience maintaining or modernising legacy systems.

• Perl experience or experience working across multiple programming languages.

• Payment gateways or financial systems you have worked on.

• Third-party API integrations you have implemented.

• Webhook, callback and retry mechanisms you have designed.

• Your experience with Docker and CI/CD.

• Work completed with AWS or serverless infrastructure.

• Any experience with Kafka or event-driven systems.

• Examples of high-availability or high-throughput systems you have supported.

• Modernisation or migration projects you have contributed to.

Applications are processed directly by payabl. cyprustech.careers is presenting this vacancy for informational purposes and is not acting as the employer or recruitment agency for this position.