Senior Backend Engineer, Klar

• 5+ years of professional backend software development experience
• Strong proficiency in Java (Java 17/21) and the Spring Boot ecosystem (Spring Data JPA, Spring Kafka, Spring Retry)
• Solid experience designing and operating REST APIs in a microservices architecture, including API documentation (OpenAPI/Swagger)
• Hands-on experience with relational databases (PostgreSQL preferred) and schema migration tools (Flyway or similar), including migrations on large, high-traffic tables
• Experience building event-driven systems with message brokers such as Apache Kafka (producers, consumers, retry/error handling)
• Strong grasp of testing practices: JUnit 5, Mockito, AssertJ, Testcontainers, and writing tests for asynchronous/event-driven flows
• Comfort working with monetary/financial calculations that demand precision and correctness (e.g., BigDecimal, rounding, fee/interest computation)
• Familiarity with containerized local development (Docker, Docker Compose) and CI/CD pipelines
• Strong communication skills and the ability to work with cross-functional, non-technical stakeholders (e.g., Risk and Finance teams)

Desirable

• Design, implement, and own backend services and APIs across the loan lifecycle, from technical design through production rollout
• Write clean, well-tested, maintainable Java code following the team's engineering standards (checkstyle, code review, high test coverage)
• Build and evolve Kafka-based event producers/consumers that keep credit, accounting, and risk systems in sync
• Author safe, backward-compatible database migrations for a system with large, continuously-written tables
• Collaborate closely with Risk, Data Science, Product, and Accounting stakeholders to translate business and regulatory requirements into system behavior
• Participate in code reviews, design discussions, and incident response; mentor other engineers on the team
• Write and maintain unit, integration, and contract tests to guard the correctness of financial calculations and state transitions
• Loan lifecycle engine: offer generation, loan creation, disbursement, fee accrual, repayment (manual and automatic), prolongation, and loan write-off
• Risk & policy integration: enforcing credit limits and rule-engine-driven eligibility policies defined by the Risk team, and integrating credit scoring and KYC signals into loan offer decisions
• Financial correctness: precise monetary calculations (principal, fees, VAT, interest), repayment ordering, and accounting-consistent state transitions regulatory requirements
• Product expansion: extending support for new credit products such as personal loans, credit lines, and BNPL, each with distinct billing cycles and repayment rules
• Platform reliability: observability (Prometheus/Grafana, OpenTelemetry), database migrations at scale (Flyway on high-volume tables), and safe rollout of changes to a system handling millions of active loans