Senior Java & SQL Developer (High‑Concurrency Systems)

About the role

We are looking for a Senior Java & SQL Developer to design, build, and optimise high‑performance enterprise applications, particularly student registration platforms that experience heavy concurrent usage. You will ensure system stability during peak loads, resolve performance bottlenecks, and lead both application and database tuning initiatives.

Key responsibilities

• Design and develop scalable, high‑performance Java backend services.
• Analyse system behaviour under load and implement performance optimisations.
• Perform advanced SQL tuning, including execution‑plan analysis, indexing, and query refactoring.
• Identify and resolve bottlenecks in both application and database layers.
• Lead production troubleshooting for slow responses, timeouts, and database locks.
• Collaborate with infrastructure teams to tune JVM settings, connection pools, and server configurations.
• Implement caching, load‑balancing, and other performance‑enhancement techniques.
• Maintain clear documentation of system architecture, fixes, and optimisations.

Required profile

• Bachelor’s degree in Computer Science, IT, or a related field.
• 5+ years of hands‑on Java backend development experience.
• Strong expertise in SQL performance tuning and optimisation.
• Proven experience with high‑concurrency or high‑traffic systems.
• Solid knowledge of Java frameworks and REST API integration.
• Excellent analytical and production‑troubleshooting skills.

Required skills

• Java (backend)
• SQL performance tuning
• REST APIs
• Application servers such as WildFly or Tomcat
• JVM tuning (heap, GC, thread pools)
• Connection‑pool and datasource optimisation
• Linux server environments
• Monitoring and logging tools