Nikola Vitorović - Java Developer for Search Systems

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Valencia, Serbia

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Experience

Jan 2022 - Present

4 years 8 months

Java Developer

Grid Dynamics

As a Search Engineer, I contributed to several high-impact projects focusing on developing and maintaining scalable and distributed systems using technologies like GCP, Elasticsearch, Java 17 (Spring Boot), and PostgreSQL across microservices, ensuring high availability and fault tolerance.
Search Engine Project: Worked on migration from old search engine to Google VertexAi from scratch, including reading Google documentation, comparing capabilities, planning priority features, and supporting unsupported legacy features.
Building search engine ecosystem: Built new microservices around the core search system to allow dynamic and configurable search requests, improving speed and reliability.
Technical refinements: Discussed roadmap and new features with client, drafted technical designs and documentation, and planned sprints.
Bug fixing, debugging, testing: Diagnosed issues via Elasticsearch logs, reproduced bugs locally and in QA/STRESS environments, implemented fixes, and covered with tests.
Implemented new features by analyzing Jira business tickets, creating technical tickets with acceptance criteria, evaluating technology choices, and collaborating with colleagues and client.
Optimization and technical debt management: Improved response times via caching and SQL query optimizations, refactored code, and added corner case tests.
Automated GitHub workflows to accelerate CI/CD.
Configured GCP services and collaborated with SREs to deploy infrastructure using Terraform, monitored logs and load patterns.
Migrated core microservice to Spring Boot 3, resolving library incompatibilities and ensuring regression, smoke, automation, and manual testing.
Developed in-house Elasticsearch integration to enable configurable searches and reduce load on Google Search Engine.
Wrote Airflow Python scripts to automate processes and schedule function calls.
Reviewed pull requests, assisted QA with testing, and authored documentation for business users.

Aug 2019 - Nov 2021

2 years 4 months

Software Engineer

FIS

At FIS, worked on a Java web application for portfolio valuation, handling complex business logic and integrating multiple technologies to ensure smooth communication across services.
Portfolio valuation project: Developed an application using EJB architecture, built EAR files with Maven, and deployed on Wildfly servers.
Messaging integration: Used JMS API for internal communication, sent XML files, and populated them with JAXB.
RabbitMQ integration: Migrated from a legacy messaging engine to RabbitMQ due to vendor support discontinuation.
UI development: Collaborated with front-end developers to display results on a GWT-based UI.
System optimization: Ensured efficient data handling, validation, and processing for accurate portfolio valuation.

Apr 2018 - Aug 2019

1 year 5 months

Junior Java Developer

OMNI LOGIKA D.O.O

Tax Administration Project: Developed a Java web application using EJB architecture, built EAR files with Maven, and deployed on Wildfly servers.
Internship: Completed a 4-month internship learning documentation and working on pet projects using Java AWT and Java Core.

Industry Experience

See where this freelancer has spent most of their professional time.

Experienced in Information Technology, Banking and Finance, and Government and Administration.

Information Technology

Banking and Finance

Government and Administration

Business Area Experience

See which departments and functions this freelancer has contributed to most.

Experienced in Information Technology and Product Development.

Information Technology

Product Development

Skills

Java 17 (Spring Boot)
Gcp (Cloudrun, Gke, Pubsub, Bq, Sql, Secret Manager, Vertexai, Airflow)
Hibernate
Git
Elasticsearch
Maven
Gradle
Postgresql
Mysql
Linux
Windows

Languages

English

Advanced

Serbian

Intermediate

Education

Oct 2011 - Jun 2016

University of Belgrade

Bachelor of Science · Electrical Engineering and Computer Science · Belgrade, Serbia

Certifications & licenses

Google Cloud Certified Associate Cloud Engineer

Google Cloud

Statistics

Experience

Total positions 3

Experience in Information Technology 4.5 y

Avg length 2 y 9 m

Longest experience 4 y 7 m

Expertise

Recent roles Java Developer, Software Engineer, Junior Java Developer

Main industries Information Technology, Banking and Finance, Government and Administration

Main business areas Information Technology, Product Development

Qualifications

Highest degree Bachelor

Certifications earned 1

Profile

Created

November 2025

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Frequently asked questions

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Nikola is based in Valencia, Serbia.

Nikola speaks the following languages: English (Advanced), Serbian (Intermediate).

Nikola has at least 8 years of experience. During this time, Nikola has worked in at least 3 different roles and for 3 different companies. The average length of individual experience is 3 years and 9 months. Note that Nikola may not have shared all experience and actually has more experience.

Based on recent experience, Nikola would be well-suited for roles such as: Java Developer, Software Engineer, Junior Java Developer.

Nikola's most recent position is Java Developer at Grid Dynamics.

In recent years, Nikola has worked for Grid Dynamics and FIS.

Nikola is most experienced in industries like Information Technology, Banking and Finance, and Government and Administration.

Nikola is most experienced in business areas like Information Technology and Product Development.

Nikola has recently worked in industries like Information Technology and Banking and Finance.

Nikola has recently worked in business areas like Information Technology.

Nikola holds a Bachelor in Electrical Engineering and Computer Science from University of Belgrade.

Nikola has 1 certificate: Google Cloud Certified Associate Cloud Engineer.

Nikola is immediately available full-time for suitable projects.

Daily Rate Distribution

0 2 4 6 8

<€320 €400-480 €560-640 €720+

The rates shown represent the typical market range for freelancers in this position based on recent contracts on our platform.

Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.

Average rates for similar positions

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800

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Daily rate avg. 625 €

The average daily rate is the mean of all daily rates from recent contracts of comparable freelancers on our platform.

800

600

400

200

Median rate 600 €

The median daily rate is the middle value of all daily rates — half of comparable freelancers charge less, half charge more. Unlike the average, it is barely affected by outliers.

Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.