Mission-Critical Java Engineer for Financial Transaction and Payment Systems
Budget: $15 – $25 USD
Senior Java Engineer — Core Transaction Systems / Distributed Processing
Role Overview
We are seeking a senior Java engineer to build and maintain high-performance, mission-critical backend systems responsible for transaction processing, state management, and data integrity.
This role focuses on designing deterministic execution systems, transactional processing engines, and scalable backend services with strict consistency and audit requirements.
Key Responsibilities
Design and implement core backend systems in Java for transaction processing
Build and maintain high-performance, stateful processing engines
Develop domain-driven models for complex business logic
Implement robust data consistency and integrity mechanisms
Design and optimize database interactions (PostgreSQL or similar)
Build and maintain asynchronous processing systems consuming message queues
Implement idempotency, concurrency control, and fault-tolerant processing
Develop journaling, logging, and audit frameworks
Collaborate with distributed system teams to integrate upstream services
Ensure system reliability, scalability, and performance under load
Required Qualifications
7+ years of backend development experience with strong Java expertise
Experience building high-throughput, low-latency systems
Strong understanding of concurrency, multithreading, and synchronization
Experience with transactional systems and data integrity patterns
Strong experience with relational databases (PostgreSQL preferred)
Experience with message-driven architectures (SQS, Kafka, etc.)
Solid understanding of object-oriented design and design patterns
Experience with Linux-based environments
Experience with cloud platforms (AWS preferred)
Preferred Qualifications
Experience with distributed systems and event-driven architectures
Experience with financial transaction systems, ledgers, or accounting systems
Experience implementing audit, logging, and traceability frameworks
Experience with performance tuning and system optimization
Experience with Spring Boot or similar frameworks (optional, not required)
Financial services or payment systems experience is a plus
What We’re Looking For
Strong engineering discipline with focus on correctness and reliability
Ability to design deterministic and auditable systems
Deep understanding of system behavior under concurrency
Ownership mindset with attention to edge cases and failure scenarios
Role Overview
We are seeking a senior Java engineer to build and maintain high-performance, mission-critical backend systems responsible for transaction processing, state management, and data integrity.
This role focuses on designing deterministic execution systems, transactional processing engines, and scalable backend services with strict consistency and audit requirements.
Key Responsibilities
Design and implement core backend systems in Java for transaction processing
Build and maintain high-performance, stateful processing engines
Develop domain-driven models for complex business logic
Implement robust data consistency and integrity mechanisms
Design and optimize database interactions (PostgreSQL or similar)
Build and maintain asynchronous processing systems consuming message queues
Implement idempotency, concurrency control, and fault-tolerant processing
Develop journaling, logging, and audit frameworks
Collaborate with distributed system teams to integrate upstream services
Ensure system reliability, scalability, and performance under load
Required Qualifications
7+ years of backend development experience with strong Java expertise
Experience building high-throughput, low-latency systems
Strong understanding of concurrency, multithreading, and synchronization
Experience with transactional systems and data integrity patterns
Strong experience with relational databases (PostgreSQL preferred)
Experience with message-driven architectures (SQS, Kafka, etc.)
Solid understanding of object-oriented design and design patterns
Experience with Linux-based environments
Experience with cloud platforms (AWS preferred)
Preferred Qualifications
Experience with distributed systems and event-driven architectures
Experience with financial transaction systems, ledgers, or accounting systems
Experience implementing audit, logging, and traceability frameworks
Experience with performance tuning and system optimization
Experience with Spring Boot or similar frameworks (optional, not required)
Financial services or payment systems experience is a plus
What We’re Looking For
Strong engineering discipline with focus on correctness and reliability
Ability to design deterministic and auditable systems
Deep understanding of system behavior under concurrency
Ownership mindset with attention to edge cases and failure scenarios