Publication
Get Started With Microservices: A Dropwizard Tutorial
https://www.toptal.com/developers/java/dropwizard-tutorial-microservices
Dusan is available for hire
Hire DusanDusan Simonovic
Verified Expert in Engineering
Java Developer
Belgrade, Serbia
Toptal member since February 8, 2017
Bio
Dusan is a full-stack Java and React developer with 15 years of software development experience. He's worked on several large projects, including Price2Spy, a tool for data web scraping for tracking competitor pricing on online shops, a social marketing tool for Adobe Marketing Cloud, an in-flight connectivity tool for a leading airline connectivity provider, and API integrations for a SaaS analytics provider.
Portfolio
Gartner
React, Java, Full-stack, Spring Boot
Secure Staffing LLC
Angular, React, Java
Patagonia Insurance, LLC
Spring, Java, React, Spring Boot
Experience
- Java - 15 years
- Spring - 15 years
- Amazon Web Services (AWS) - 12 years
- Apache Kafka - 9 years
- REST - 9 years
- Spring Boot - 9 years
- Docker - 7 years
- Microservices - 7 years
Preferred Environment
Apache Maven, Gradle, Windows, MacOS, Git, IntelliJ IDEA
The most amazing...
...project I've worked on is a huge social network marketing platform for Adobe Marketing Cloud.
Work Experience
Full-stack Java/React Developer
2022 - 2025
Gartner
- Worked on developing a Google Chrome extension to display Google search results along with the results from the Gartner website for the logged-in user.
- Operated on Gartner home page as a back-end developer, managing multiple core microservices.
- Worked on developing and maintaining multiple AWS Lambda functions for various background processes.
- Developed and managed infrastructure as a code (Terraform) module for the backing infrastructure for the microservices and Lambda functions I owned.
Technologies: React, Java, Full-stack, Spring Boot
Front-end Angular and React Developer
2020 - 2022
Secure Staffing LLC
- Was a part of the development team working on a high-load website as a full-stack developer.
- Used Asana to track work items and bugs and collaborate with the team.
- Worked on a product for live video streaming with very high traffic.
Technologies: Angular, React, Java
Senior Full-stack Developer
2019 - 2019
Patagonia Insurance, LLC
- Built a React-based front-end app from existing designs.
- Built a Java/Spring back end for our web platform.
- Implemented a full CI/CD pipeline using GitHub CI.
- Set up AWS infrastructure for front end, back end, email sending, and more.
- Integrated our web platform with various 3rd-party APIs (e.g., TrustedForm, LeadID, Google Tag Manager, Google Analytics, or Maxminds).
Technologies: Spring, Java, React, Spring Boot
Senior Full-stack Developer
2018 - 2019
U Group (former Bytecubed) (via Toptal)
- Architected the Kafka backbone that is being used for event-based messaging between multiple microservices.
- Made key contributions to module integration architecture through the Kafka backbone.
- Developed back-end features in Java Spring and front ends in Angular and React.
Technologies: Angular, React, Apache Kafka, Java, Spring, Spring Boot
Senior Java Engineer
2018 - 2018
Datasnap, Inc. (via Toptal)
- Implemented a data processing pipeline for processing trading events from a NASDAQ trading platform.
- Achieved a very high throughput/low latency data processor. 10GB of data (360 million trading events) is processed (data transformation, aggregation, joins) in less than 20 minutes. End-to-end latency at the end of the project was below 1 millisecond.
- Implemented a pluggable model to support different input reading and output format implementations.
- Maintained full integration testing in a Docker container.
- Built a full CI/CD pipeline to deploy the code to AWS with no downtime.
Technologies: Continuous Deployment, Continuous Integration (CI), Apache Kafka, Java, Spring Boot, Stock Price Analysis, High-load, Data Processing, Time Series Data
Senior Java Developer
2017 - 2018
MetaSaas (via Toptal)
- Worked on integrations with various SaaS vendors using mostly REST.
- Reviewed code and handled approvals for other developers.
- Mentored and helped new developers start with integrations.
- Developed an expenses matching mechanism using Expensify API and Elasticsearch.
- Helped create integration testing for new integrations.
Technologies: MyBatis, Elasticsearch, OAuth, JSON Web Tokens (JWT), REST, Java, SaaS Operations (SaaSOps), Spring Boot
Senior Java Developer
2017 - 2018
Gogo, LLC
- Led the development of a back-end tool used by airlines to track usage of the GogoAir in-flight entertainment system in real time.
- Developed microservices (Spring REST services—Spring Cloud, Netflix OSS, AWS).
- Built a deployment process (Netflix OSS, AWS, Spring Cloud).
- Refactored some of the legacy code and migrated data from a data center to the cloud.
- Enhanced security in an existing system by introducing asymmetric private/public key JWT token authentication.
Technologies: Amazon Web Services (AWS), Spring Cloud, Java, Spring Boot, Netflix OSS, Apache Kafka, React, JavaScript, Amazon DynamoDB, MySQL
Senior Java Engineer/Scrum Master
2015 - 2017
Endava d.o.o.
- Led the remote element of a technical team in San Jose (USA), Belgrade (Serbia), and Noida (India).
- Developed core services for the Adobe social media marketing platform.
- Built a link shortening service to be used across the platform.
- Created a label management service for managing content tags/labels.
- Developed an asset service to store user assets to Amazon S3.
- Presented at "Pass it on" sessions to help other members of the company to gain knowledge.
Technologies: Agile, Scrum, Git, MySQL, HBase, JDBI, Jersey, REST, Dropwizard, Java, Spring Boot, Social APIs
Web Developer and System Administrator
2010 - 2015
Webcentric d.o.o.
- Contributed to the development of a tool for monitoring competitor prices on online shops.
- Handled the deployment lifecycle of the application.
- Maintained all application environments from development to production.
- Architected a huge MariaDB Galera cluster with multiple nodes.
- Mentored juniors and worked on developing them as professionals.
- Set up and maintained a CI environment for deploying a custom Java application to a large set of remote VPS servers with no downtime.
- Developed full-stack features (Java back-end, HTML/CSS/JS on UI).
Technologies: JPPF, Subversion (SVN), Spring, MariaDB, MyBatis, Java, Spring Boot, JavaScript
Experience
Price2Spy
http://www.price2spy.comA tool used by web shop owners to monitor their competitors. By using this tool, they get notified about all the changes that happen on their competitors' shops, so they can react accordingly with price or any other adjustments.
Adobe Social - Core Services
https://www.youtube.com/watch?v=eIoGqPqKAv8This tool is a huge set of modules that helps enterprise clients set up and maintain their social media marketing campaigns. This project was developed for a world-leading IT company, and its clients are some of the world's top companies.
MetaSaas Platform
MetaSaas is the best SaaS management tool for medium and large businesses. Manage SaaS vendors, reduce SaaS spend, and manage cloud applications from a single and easy-to-use dashboard.
As part of the MetaSaas team, my role was to develop more complicated integrations with SaaS vendors and to review and quality-check code for other developers. This involved using REST, OAuth, JWT, and more.
As part of the MetaSaas team, my role was to develop more complicated integrations with SaaS vendors and to review and quality-check code for other developers. This involved using REST, OAuth, JWT, and more.
Gogo, Ltd.
https://www.gogoair.com/Gogo is a leading in-flight connectivity and entertainment provider. As a member of the development team in Belgrade, I was involved in back-end and front-end development of the cloud solution for Airlines to track usage of the system in airplanes. This involved back-end development (Spring cloud, Netflix OSS) and UI (React and Redux).
Datasnap JTrain
A high-volume/low-latency data processing tool that processes events from the NASDAQ trading platform and produces output. This tool involved data lookup (joins), aggregation, and data transformation.
EinsteinMedicare
A web platform used to connect insurance buyers with insurance companies. It presents a multi-step form to a customer, which generates a lead that is sent to insurance companies. The back end is Java/Spring, and the front end is React, with full Gitlab CI/CD pipelines for auto deployments with zero downtime, all on the AWS infrastructure.
Education
2009 - 2009
Cisco Certified Network Associate in Computer Networking
Cisco Net Academy - FTN Rao, Novi Sad Serbia
2000 - 2006
Master's Degree in Microcomputer Electronics
Faculty of Technical Sciences - Novi Sad
Certifications
DECEMBER 2022 - DECEMBER 2025
AWS Certified Solutions Architect — Associate
Amazon Web Services
Skills
Libraries/APIs
React, Apache Lucene, JDBI, MyBatis, Social APIs
Tools
RabbitMQ, Apache Solr, IntelliJ IDEA, Git, Gradle, Apache Maven, Subversion (SVN), GitLab CI/CD
Languages
SQL, Java, TypeScript, JavaScript
Frameworks
Spring, OAuth 2, Dropwizard, JUnit, Angular, Spring Boot, Jersey, JSON Web Tokens (JWT)
Paradigms
Reactive Programming, Microservices, Back-end Architecture, Continuous Delivery (CD), Scrum, Test-driven Development (TDD), Continuous Integration (CI), REST, Agile, Continuous Deployment
Platforms
Amazon Web Services (AWS), Docker, Apache Kafka, MacOS, Ubuntu, Windows, Linux
Storage
MongoDB, Amazon DynamoDB, Microsoft SQL Server, H2, Redis, MySQL, MariaDB, Elasticsearch, HBase, Cassandra, Databases
Other
Netflix OSS, Networks, JPPF, Spring Cloud, OAuth, SaaS Operations (SaaSOps), Full-stack, Galera Cluster, Scrum Master, Cloud Computing, Leadership, Multithreading, High-load, Data Processing, Time Series Data, Stock Price Analysis
Collaboration That Works
How to Work with Toptal
Toptal matches you directly with global industry experts from our network in hours—not weeks or months.
1
Share your needs
Discuss your requirements and refine your scope in a call with a Toptal domain expert.
2
Choose your talent
Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.
3
Start your risk-free talent trial
Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.
Top talent is in high demand.
Start hiring