Vishnu Rajeev

Java Backend Developer

Java • Spring Boot • REST APIs • PostgreSQL

I build backend systems in Java and Spring Boot — REST APIs, customer-specific software, and the relational-database work behind them. Currently doing this for enterprise customers at Scheer IMC in Germany.

Portrait of Vishnu Rajeev

About

I'm a backend developer based in Saarbrücken, Germany, focused on Java and Spring Boot.

Right now I build and maintain REST APIs and customer-specific features inside a large enterprise learning platform at Scheer IMC — working in an established Java codebase, modelling data in PostgreSQL and SQL Server, and shipping reliable changes to production systems that real customers depend on.

Before backend became my focus, I worked across full-stack web development, conversational AI, and research software. That range taught me how different systems fit together — but API design, data modelling, and writing code that stays maintainable are what I want to go deep in.

I care about understanding why a system behaves the way it does, not just getting a feature to pass. Clean data models, sensible APIs, and code the next person can actually work with.

Experience

Download CV

Junior Software Developer Customer Solutions

Scheer IMC AG

Work primarily on Java backend development for customer-specific solutions within an enterprise learning platform. Build and maintain REST APIs, implement backend functionality, work with relational databases, investigate customer requirements, and debug and modify existing production systems. The role involves working within an established Java codebase and implementing reliable changes for enterprise customer environments.

  • Java
  • REST APIs
  • SQL
  • PostgreSQL
  • SQL Server
  • IntelliJ IDEA

Software Developer

PixelFree Studio Germany UG

Worked across frontend and backend development on web applications and customer-facing software. Contributed to application features, API integrations, and reusable frontend functionality while collaborating within a small product-focused development team. Worked with React and GraphQL on frontend applications and Python and Flask for backend functionality.

  • React
  • JavaScript
  • GraphQL
  • Python
  • Flask
  • HTML
  • CSS

Research Assistant — Software Development

Fraunhofer Institute for High-Speed Dynamics, Ernst-Mach-Institut (EMI)

Worked on software development in an applied research environment at Fraunhofer EMI, across web development, visualization, and .NET. Built the LSQRA (Laser Safety Quantitative Risk Analysis) tool in C++ for a defense-sector client. For my master's thesis, I developed an authentication library for ASP.NET Core — authentication flows, JWTs, SignalR integration, and application-side data persistence. The work gave me experience designing reusable software components and working independently on larger technical problems in a research environment.

  • C#
  • ASP.NET Core
  • C++
  • TypeScript
  • Vue.js
  • Three.js
  • SignalR
  • JWT
  • LiteDB

Cognitive Implementation Engineer

Amelia (now SoundHound AI)

Developed enterprise conversational AI solutions for clients including JPMorgan Chase, Visionworks, and Resorts World using the Amelia platform. Implemented backend logic, conversational workflows, and API-based integrations connecting the platform with external enterprise systems. Translated business requirements into conversational and automated workflows while developing the supporting integration logic.

  • Java
  • Groovy
  • Python
  • Apache Camel
  • REST APIs
  • BPMN
  • Conversational AI
  • NLP

Software Engineer Trainee

MountBlue Technologies

Completed an intensive software engineering training program focused on backend and web application development. Built applications using Java and Spring Boot, worked with relational databases through JPA, and gained practical experience developing database-backed web applications.

  • Java
  • Spring Boot
  • Spring MVC
  • Spring Data JPA
  • PostgreSQL
  • Thymeleaf
  • HTML
  • CSS

Selected work

Personal Project — Workout Tracking API

LiftTrack

Java • Spring Boot • PostgreSQL • REST

A backend application that models workouts, exercises, sets, users, and progress through a REST API over PostgreSQL.

What it does:

  • Create and retrieve exercises
  • Manage workout sessions and add exercises to them
  • Record sets, reps, and weight
  • Compute workout progress statistics
  • Input validation and structured error handling

Built to go deeper on API design, relational data modelling, and writing a backend that holds up as it grows.

Professional Project — PixelFree Studio

Accessibility Widget

HTML • CSS • JavaScript

Built a drop-in web accessibility widget from scratch in vanilla JavaScript, HTML, and CSS — delivering a working first version in 2 weeks and deploying it across 10+ client websites.

Implemented 15+ accessibility features, including contrast and saturation controls, text scaling and spacing, dyslexia-friendly mode, screen-reader support, selectable user profiles, and a multi-language UI.

Persisted user settings across the site via localStorage and used Shadow DOM isolation so host-site styling couldn't break the widget.

Designed a template-and-config system that generated fully branded client widgets (custom color scheme and logo) in seconds instead of hours — turning per-client setup from manual work into a near-instant process.

Technical skills

Core

Java, Spring Boot, REST APIs, PostgreSQL, SQL Server, JPA/Hibernate

Also work with

Python/Flask, React, TypeScript, GraphQL, C#/ASP.NET Core

Tools & Platforms

Git, Docker, Maven, Postman, IntelliJ IDEA, Jira, Confluence, Linux

Education

2023 – 2024

Master of Science — Information Technology Management

Berlin School of Business and Innovation

Berlin, Germany · Final Grade: 1.8

Completed my master's thesis in collaboration with Fraunhofer EMI, developing an authentication library for ASP.NET Core applications.