
Senior Go Engineer (Core Banking)
Primary stack
Nice to have's
Job description
About the Position
At Colibrix One, we're building advanced, AI-powered payment technologies that support Payment Service Providers (PSPs), Electronic Money Institutions (EMIs), and neobanks across the EU and the UK. As a fully licensed Electronic Money Institution (FCA Reference No. 927920) and holder of a Financial Institution Licence issued by the MFSA, as well as a principal member of both VISA and Mastercard, we provide comprehensive, real-world financial solutions that include:
- Global card processing
- Digital wallet infrastructure
- Cross-border merchant accounts
- Alternative payment methods (APMs)
- Corporate accounts for legal entities
We're a fast-growing team with a passion for innovation, security, and scalability. Our culture values curiosity, collaboration, and impact - and we're looking for talented professionals who are ready to shape the future of fintech.
At Colibrix One, your work directly powers the digital economy. If you're eager to solve meaningful challenges and build with purpose, we'd love to hear from you.
We're seeking an experienced Senior Go Engineer (Core Banking) to join our team and contribute significantly to our payment gateway product. The ideal candidate will bring deep technical expertise, a collaborative mindset, and the ability to influence and mentor team members through knowledge and experience rather than formal authority.
Responsibilities
- Design and develop scalable backend services
- Write clean, maintainable code
- Collaborate with frontend team
- Integrate with banks, payment providers, processors, AML/KYC, or anti-fraud platforms
- Ensure security requirements for financial and personal data
Requirements
- 5+ years of professional Go development experience, including 3+ years in fintech, banking, payments, or other transaction-critical systems
- Strong knowledge of distributed systems, microservices, and API design (REST and gRPC)
- Advanced PostgreSQL skills, including transactions, isolation levels, locking, indexing, migrations, and concurrency
- Experience designing reliable transactional systems using idempotency, retries, event deduplication, transactional outbox, sagas, and reconciliation
- Hands-on experience with event-driven architectures and message brokers such as NATS, Kafka, or RabbitMQ
- Experience building and operating production services, including incident investigation, safe deployments, database migrations, and observability
- Practical knowledge of AWS, Kubernetes, and CI/CD
- Understanding of security requirements for financial and personal data
- Ability to translate business requirements into technical solutions and independently drive implementation
- Strong communication skills and working proficiency in Russian and English
Nice to Have
- Experience with Temporal or a similar workflow engine
- Experience with NATS/JetStream, GitLab CI/CD, OpenTelemetry, Prometheus, Grafana, Loki, or Tempo
- Knowledge of event sourcing or append-only financial data models
- Familiarity with PCI DSS and GDPR
- Experience using AI coding tools for analysis, implementation, testing, or code review
We Offer
- Opportunity to shape the future of fintech solutions within a growing company
- Collaborative, horizontal team structure that values your expertise and ideas
- Continuous learning and development opportunities to enhance your skills and career growth
- Competitive salary and benefits package
- Flexible work arrangements to support work-life balance
About the Company
At Colibrix One, we're building advanced, AI-powered payment technologies that support Payment Service Providers (PSPs), Electronic Money Institutions (EMIs), and neobanks across the EU and the UK. As a fully licensed Electronic Money Institution (FCA Reference No. 927920) and holder of a Financial Institution Licence issued by the MFSA, as well as a principal member of both VISA and Mastercard, we provide comprehensive, real-world financial solutions that include:
- Global card processing
- Digital wallet infrastructure
- Cross-border merchant accounts
- Alternative payment methods (APMs)
- Corporate accounts for legal entities
We're a fast-growing team with a passion for innovation, security, and scalability. Our culture values curiosity, collaboration, and impact - and we're looking for talented professionals who are ready to shape the future of fintech.
© Mellifera Operations Limited. This job description was sourced from the employer's public career page. TheJob is not the employer — we index the posting and route candidates to the source. All content rights and hiring decisions belong to the employer.
Mellifera specializes in exceptional BPM solutions that are built on a foundation of dedication, integrity, and excellence. Our offerings reflect the unwavering commitment and quality-focused ethos embodied by our namesake, the Honey Bee.
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