Experienced, Senior Core Java (Java 8). Fundamental coding needs to be strong. -multi-threading, collections of API, JDBC and knowledge of Java profiling tools. -Lambda and stream. -Map and group by example in stream. Spring boot / Spring JPA / Spring Hibernate. EXPERIENCE with Java Spring in Finance, handling large volume. Ask candidate: -Benefits using Spring boot. -How auto configuration works in spring boot. -How to configure for different environments like dev, uat and prod or what is profile in spring boot. -Annotation used in Rest Api and their usage. -JPA Repository implementation. -Eager and lazy loading in JPA. Big Data technologies and frameworks: preferably Apache Hadoop. Apache Spark, Apache Hive, or Apache Flink are okay too. Confirm with candidate / dig into their Big Data depth with: -Discover, ingest, and incorporate new sources of real-time, streaming, batch, and API-based data into our platform. -Loading and managing large data in Hadoop. Computing complex logic in spark platforms.