Senior Software Engineer (Backend) (Web3)

TL;DR

Senior Software Engineer (Backend) (JVM/Blockchain): Designing and building core blockchain infrastructure and stablecoin payments rails with an accent on high-performance backend services and multi-chain integration. Focus on ensuring reliability and security of digital asset custody and on-chain transaction processing at scale.

Location: Hybrid in South Africa, Bulgaria, Poland, or Spain

Salary: Bulgaria €70,000–€110,000 | Spain €85,000–€110,000 | Poland 250,000–480,000 PLN

Company

hirify.global is a financial services company accelerating global money movement through stablecoin-native infrastructure.

What you will do

• Design, develop, and maintain high-performance backend services for blockchain integrations and digital asset custody.
• Build and evolve integrations with blockchain networks and providers to support multi-chain, multi-asset operations.
• Develop APIs for the full digital asset lifecycle, including address generation, deposits, withdrawals, and balance management.
• Drive improvements in system observability, performance, and resilience, including monitoring and incident response.
• Collaborate with cross-functional squads to deliver high-impact features and uphold engineering standards.
• Mentor peers, share knowledge, and contribute to the team's engineering culture.

Requirements

• 5+ years of experience as a backend engineer with deep proficiency in Java, Kotlin, or similar JVM-based languages.
• Experience designing and operating microservices in a distributed systems environment.
• Solid understanding of relational databases (e.g., PostgreSQL) and event-driven architectures (e.g., Kafka, SQS/SNS).
• Experience with cloud platforms (AWS, GCP, or Azure) and containerization (Docker, Kubernetes).
• Familiarity with CI/CD and infrastructure-as-code concepts.
• Must be based in South Africa, Bulgaria, Poland, or Spain.

Nice to have

• Experience with blockchain technologies, cryptocurrency infrastructure, or digital asset custody systems.
• Understanding of wallet architecture, key management, or self-custody patterns.
• Experience in fintech, payments, or other high-availability transactional systems.
• Knowledge of Domain-Driven Design (DDD) and hexagonal architecture.

Culture & Benefits

• Competitive salary and a flexible approach to holiday.
• Hybrid work model with flexible working hours.
• Culture built on passionate, growth-minded people.
• Opportunities to travel to global offices.
• Open and creative environment to help define the future of the company.