Senior Java Developer – Oracle ADF, PL/SQL, React, Spring- Legacy Healthcare Modernization

Posted 1 hour ago

Worldwide

Summary

Location: Remote (EU Preferred, Open to Global Candidates)  Employment Type: Contract / Full-Time  Experience: 8+ Years 1. PROJECT OVERVIEW The Company is modernizing an enterprise healthcare application estate currently built on Oracle ADF. The engagement covers the redevelopment of approximately 1,250 ADF screens into React-based web components served by an existing Spring Boot middleware (The Product Common Backend). Core business logic resides in the Oracle database (PL/SQL packages, triggers, functions) and remains there — the middleware is a thin orchestration layer where backend operations are registered declaratively, not coded as services. This is a like-for-like functional migration: business behavior embedded in the ADF screens must be accurately interpreted and preserved, not redesigned. Scope ~1,250 Oracle ADF screens migrated to React web components on The Product. Common Backend (Spring Boot) Architecture rule:e Business logic remains in Oracle PL/SQL; middleware carries no business logic. Engagement model: Outsourced development under The Company architectural governance Standards: The Company-defined development framework and coding standards (mandatory compliance) 2. REQUIRED CANDIDATE CAPABILITIES Candidate must demonstrate: • Oracle ADF interpretation — Hands-on ability to read ADF task flows, page definitions, bindings, and embedded business rules, and translate them into screen specifications for redevelopment. • React web component delivery — Production-grade experience building componentized, independently versioned React web components consuming REST APIs. • PL/SQL & registration framework — Ability to read PL/SQL packages, triggers, and Oracle types (STRUCT/ARRAY/REF CURSOR) and register queries and PL/SQL operations through The Company's declarative registration framework. Deep Spring internals are not required; the framework abstracts them,m but disciplined use of it is. • Business interpretation — Capability to infer and preserve business intent directly from existing screens and database code where documentation is limited, without introducing logic into the middleware layer. 3. DEVELOPMENT FRAMEWORK & STANDARDS Development is performed on The Company's existing The Product Common Backend framework: backend operations (queries, PL/SQL blocks, Java functions) are registered declaratively and auto-exposed as REST endpoints; frontend modules ship as independently versioned React web components. The framework documentation, reference architecture, and coding standards will be issued by the Company Solution Architect at engagement start. Strict compliance is a condition of the contract — in particular, no business logic may be implemented in the middleware layer. Non-conforming code can be returned for rework on cost terms. Note: Candidate should submit: (a) His/her profile and relevant ADF-to-modern-stack migration references. (b) Portfolio/Profile of about his/her capabilities as defined in "Section 2" (c) Proposed delivery approach along with timeline For this Project, we are looking for an experienced Senior Java Developer to help modernize a 30-year-old enterprise healthcare platform. The ideal candidate will have strong experience working with Oracle ADF and PL/SQL, along with modern Java technologies such as Spring Framework and React. You will play a key role in migrating legacy Oracle ADF screens into a modern React-based UI while ensuring seamless integration with the existing backend systems. This is a highly technical role requiring experience with enterprise legacy systems, Oracle databases, and gradual application modernization. Key Responsibilities Analyze and maintain an existing Oracle ADF-based enterprise healthcare application. Modernize legacy user interfaces by rewriting Oracle ADF screens using React. Develop and maintain backend services using Spring Framework/Spring Boot. Design and optimize complex PL/SQL packages, procedures, triggers, and functions. Integrate modern React applications with existing Oracle-based backend services. Ensure compatibility with a large-scale legacy healthcare system while minimizing business disruption. Collaborate with architects, product owners, QA engineers, and cross-functional teams. Perform code reviews and maintain high coding standards. Troubleshoot production issues and optimize application performance. Participate in technical design discussions and modernization planning. Mandatory Requirements: 8+ years of professional Java development experience. At least 5 years of hands-on Oracle ADF development in enterprise projects. Strong experience with Oracle Database and PL/SQL (packages, procedures, functions, triggers, performance tuning). 2–4+ years of Spring Framework/Spring Boot development. Experience rewriting Oracle ADF screens into React while integrating with existing Java/Spring services. Experience working on large-scale legacy enterprise applications, preferably in the healthcare domain. Note: To be considered for this project, your proposal must address all the requirements outlined above. Please include: Your profile and relevant Oracle ADF to modern-stack migration experience. A portfolio or profile demonstrating the capabilities listed in Section 2 (Required Candidate Capabilities). Your proposed delivery approach, estimated timeline, and any relevant references. Generic, AI-generated, or copy-paste proposals that do not specifically address these requirements will not be considered for evaluation. Only candidates with demonstrable experience relevant to this project will be shortlisted.

  • More than 30 hrs/week
    Hourly
  • 6+ months
    Duration
  • Expert
    Experience Level
  • $15.00

    -

    $20.00

    Hourly
  • Remote Job
  • Ongoing project
    Project Type
Skills and Expertise
Mandatory skills
ADF Faces
Oracle Database
Activity on this job
  • Proposals:10 to 15
  • Last viewed by client:41 minutes ago
  • Interviewing:
    0
  • Invites sent:
    0
  • Unanswered invites:
    0
About the client
Member since Apr 2, 2024
  • United States
    Sherman Oaks3:40 PM
  • $1.1K total spent
    7 hires, 0 active
  • 23 hours
  • Tech & IT
    Mid-sized company (10-99 people)

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