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Java Developer

Laiba Technologies LLCSt. Louis, MO🇺🇸United StatesPosted Sep 10, 2026

Why This Role Stands Out

This Lead/Senior Core Java Developer role offers a fantastic opportunity to leverage your extensive experience in performance tuning within the dynamic fintech sector, contributing to critical enterprise systems. You'll thrive here if you possess deep expertise in Java, JVM optimization, and diagnosing complex performance bottlenecks, with a strong preference for candidates from banking or financial services backgrounds. This on-site position is perfect for seasoned professionals seeking to make a significant impact.

Quick Overview

Seniority
Mid Senior
Work mode
On Site
Location
St. Louis, MO, United States
Posted
1 week ago
MicroservicesSQLSpringSpring BootGatlingJMeterJavaKafkaKubernetesREST

Job Description

Job Title: Lead/Senior Core Java Developer – Performance Tuning
Location: St. Louis, MO – Onsite/Hybrid
Employment Type: Contract
Experience Required: 12+ Years
Mandatory Domain Experience : Banking, Finance, Fintech
Position Overview:
We are seeking a highly experienced Lead/Senior Core Java Developer with strong hands-on expertise in Java application performance tuning, JVM optimization, multithreading, and high-volume enterprise systems.
The ideal candidate will have experience diagnosing and resolving performance bottlenecks in complex, business-critical applications. Experience working within banking, financial services, payment processing, or transaction-based environments is highly preferred.
 
Required Skills:
  • 12+ years of professional Java development experience.
  • Strong hands-on expertise in Core Java and modern Java versions.
  • Advanced knowledge of Java collections, concurrency, multithreading, synchronization, executors, and memory management.
  • Strong experience with JVM internals and JVM performance tuning.
  • Experience analyzing heap dumps, thread dumps, garbage-collection logs, CPU utilization, and memory leaks.
  • Hands-on experience with performance-profiling and monitoring tools such as Java Flight Recorder, Java Mission Control, VisualVM, YourKit, JProfiler, Dynatrace, AppDynamics, or similar tools.
  • Strong understanding of algorithms, data structures, design patterns, and object-oriented programming.
  • Experience with Spring Boot, REST APIs, and enterprise application development.
  • Strong SQL knowledge, including query analysis and database-performance optimization.
  • Experience with load and performance-testing tools such as JMeter, Gatling, or similar tools.
  • Experience troubleshooting production applications in Linux/Unix environments.
  • Strong debugging, analytical, problem-solving, leadership, and communication skills.
Preferred Skills:
  • Experience in banking, financial services, payment processing, card-processing, or transaction-management systems.
  • Experience developing low-latency and high-throughput applications.
  • Knowledge of microservices, Kafka, distributed systems, caching, and messaging technologies.
  • Experience with cloud platforms, CI/CD pipelines, Kubernetes, and application observability.
  • Previous experience working as a Technical Lead or Senior Developer.

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