TRCD-26-04413

Senior Java Developer (Oracle to PostgreSQL Migration, Hibernate 4.x)

Contract role in India for a senior Java engineer to own application-side changes for an Oracle-to-PostgreSQL database swap across 8 Java modules, with intentionally narrow scope (no framework upgrade). Work includes swapping JDBC dependencies and Hibernate dialects, validating Hibernate/JPA ORM mappings on PostgreSQL, fixing BLOB/CLOB LOB handling, translating Oracle-specific SQL patterns in 100+ DAOs and 51 maintenance scripts, and converting PL/SQL to PL/pgSQL. Requires strong Java 8, legacy Hibernate 4.x/JPA, Spring 4 XML configuration, expert Oracle and PostgreSQL SQL translation, Gradle multi-module builds; Grails/GORM/Groovy, Quartz, HikariCP, and Flyway/Liquibase are strong pluses.

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Position summary

Location: India
Workplace: Remote
Employment: Contract
Experience: Minimum 7 years and Maximum 12 years

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Role overview

Why This Role Matters.

Your Impact

Deliver Enterprise Value

Help organisations solve complex business problems through modern technology, consulting expertise and measurable outcomes.

Collaboration

Work Across Teams

Collaborate with consultants, architects, engineers and client stakeholders throughout the project lifecycle.

Growth

Learn Continuously

Gain exposure to enterprise technologies, certifications, mentoring and real-world project experience.

Career Path

Grow With Ubique

Build a long-term consulting career with opportunities to take on greater responsibility and leadership over time.

Responsibilities

What You'll Be Doing.

Every role at Ubique contributes directly to solving meaningful business challenges for our clients.

7+ years Java, including production Java 8

5+ years Hibernate/JPA with hands-on Hibernate 4.x (legacy, not just modern Spring Boot)

At least one completed Oracle→PostgreSQL (or equivalent) migration on a Java app

Expert Oracle + PostgreSQL SQL — fluent translating NVL, SYSDATE, ROWNUM, DECODE, DUAL, MERGE, CONNECT BY, sequences

Spring 4.x XML configuration and BLOB/CLOB → bytea/text LOB handling

Technology stack

Tools & Technologies.

The platforms and technologies you'll use to build modern, enterprise-grade solutions.

Java 8

Required

Hibernate 4

Required

JPA

Required

Spring 4

Required

Spring XML

Required

JDBC

Required

Oracle

Required

PostgreSQL

Required

Oracle to PostgreSQL migration

Required

SQL translation

Required

PL/SQL

Required

PL/pgSQL

Required

Gradle

Required

multi-module

Required

DAO

Required

ORM mapping

Required

Hibernate dialect

Required

BLOB

Required

CLOB

Required

bytea

Required

Requirements

Skills & Experience.

We value curiosity, collaboration and continuous learning. If you don't meet every requirement but believe you can make an impact, we'd still love to hear from you.

Essential

Required Qualifications

Java (7+ years), including production Java 8

Hibernate/JPA (5+ years) with hands-on Hibernate 4.x (legacy)

Completed Oracle to PostgreSQL (or equivalent) migration on a Java application

Expert Oracle SQL and PostgreSQL SQL; ability to translate Oracle-specific constructs (NVL, SYSDATE, ROWNUM, DECODE, DUAL, MERGE, CONNECT BY, sequences)

Spring Framework 4.x XML configuration

LOB handling: Oracle BLOB/CLOB to PostgreSQL bytea/text mapping and application handling

Gradle multi-module builds

PL/SQL to PL/pgSQL conversion

JDBC dependency swap and Hibernate dialect changes

Validate ORM mappings against PostgreSQL; fix mapping issues in DAOs/scripts

Preferred

Nice to Have

Grails 5.x

GORM

Groovy

Quartz Scheduler

HikariCP

Flyway

Liquibase

What you'll gain

More Than Just A Job.

We're committed to helping every team member grow professionally, personally and technically while working on meaningful projects.

Global Exposure

Collaborate with international clients and multicultural teams on enterprise programmes.

Continuous Learning

Expand your expertise through mentoring, certifications and hands-on project experience.

Career Growth

Take ownership, develop leadership skills and grow your consulting career over time.

Flexible Working

Hybrid and remote collaboration designed around trust and delivering exceptional outcomes.

People First

Join a supportive culture where collaboration, respect and long-term relationships come first.

Enterprise Projects

Work on meaningful technology initiatives for leading organisations across industries.

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Apply for Senior Java Developer (Oracle to PostgreSQL Migration, Hibernate 4.x)

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