Publication
Using Spring Boot for WebSocket Implementation with STOMP
https://www.toptal.com/java/stomp-spring-boot-websocket
Tomasz is available for hire
Hire TomaszTomasz Dąbrowski
Verified Expert in Engineering
Java Developer
Location
Warsaw, Poland
Toptal Member Since
October 30, 2015
Tomasz is a creative developer with over fifteen years of experience designing and implementing Java applications. He is a team player, enthusiastic about learning new technologies and trying out different ideas and approaches to process improvement. Tomasz has worked for international companies, such as Hewlett-Packard and Silicon Valley startups. Currently, he helps small and medium companies to create Java-based solutions.
Portfolio
A Non-profit Organization in Warsaw, Poland
Java, Scratch
Goalscape Software
Back-end Development, Spring, PostgreSQL, SQL, SaaS, Back-end Architecture...
DextCloud
Amazon Web Services (AWS), Google Cloud Platform (GCP), Camel, Spring Boot
Experience
Availability
Full-time
Preferred Environment
Eclipse, IntelliJ IDEA
The most amazing...
...thing I've coded is a keyword-based language for performing business operations on objects in a rapid application development system.
Work Experience
Volunteer Programming Teacher
2013 - PRESENT
A Non-profit Organization in Warsaw, Poland
- Taught adults who wanted to start a career as a programmer.
- Introduced kids to basic programming skills using robots.
- Organized a competition for the best game designed and implemented by a kid.
Technologies: Java, Scratch
Senior Back-end Developer
2023 - 2023
Goalscape Software
- Improved the performance of the back-end GraphQL API.
- Designed and implemented a module for handling attachments.
- Implemented back-end support for the Gantt charts.
Technologies: Back-end Development, Spring, PostgreSQL, SQL, SaaS, Back-end Architecture, Spring Boot, TypeScript, Cloud Architecture, Hibernate, GraphQL, APIs, Gantt Charts
Developer and Architect
2018 - 2022
DextCloud
- Created several back-end Spring Boot-based microservices that implemented back-end features and integrated with the front-end application by the REST API.
- Implemented OAuth2 Authorization Server and WebSocket server for the communication between the back-end and front-end apps.
- Designed and implemented the main logic of the application.
Technologies: Amazon Web Services (AWS), Google Cloud Platform (GCP), Camel, Spring Boot
Amazon API Gateway Expert
2018 - 2018
UAfjord, Ltd. (via Toptal)
- Integrated Shopify with Amazon SNS.
Technologies: AWS Simple Notification Service (SNS), Amazon API Gateway
Java Back-end Developer
2016 - 2018
Online Consulting Portal
- Created a job portal for business consultants in Germany.
Technologies: Angular, HTML, Play Framework, Java 8
Java Developer
2016 - 2018
Optile GmbH
- Integrated an online payment system with several payment providers and banks (e.g., Stripe, ConsultaPay, APCO, Payvision). The online payment system was written in Core Java.
Technologies: Java 8
Developer
2016 - 2017
Eprintwerx International
- Built an AWS Lambda (Java) and AWS API gateway back-end for an application that served data for marketing purposes. The project had microservice-oriented architecture.
Technologies: Amazon API Gateway, AWS Lambda, Java 8
Java Back-end Developer
2016 - 2016
ChessVision
- Built a Spring-based complex client-server system for an application that allows users to record chess games.
Technologies: RESTful Microservices, Amazon EC2, Java 8
Java/Liferay Developer
2015 - 2016
PFacto
- Created a CRM application for a Dutch energy provider company. The application based on Java portlets implemented with Liferay.
Technologies: Liferay, Java
Java AWS Developer
2015 - 2015
Graywill, LLC
- Created an application for online document generation for a small travel agency. The application was based on AWS Lambda functions.
Technologies: AWS Lambda, Java 8
Senior Java Developer
2011 - 2013
Altkom (Poland)
- Designed and implemented about five web applications for various customers using Spring and Hibernate.
- Created a desktop application using Swing and Drools.
- Completed two security and performance audits of online web applications (banking applications).
- Conducted technical interviews.
- Prepared around five high-level technical proposals for customers.
Technologies: JBoss Drools, Liferay, Hibernate, Spring, Java
Senior Developer/Designer
2004 - 2011
Hewlett-Packard
- Designed and developed web and desktop applications for various customers (around fifteen projects for big international companies).
- Prepared around fifteen high-level and low-level designs.
- Planned teamwork and reviewed results for two projects.
- Provided software measurement (e.g., function point analysis).
- Helped analyze business processes and gather user requirements for around ten projects.
Technologies: UML, SQL, Enterprise Java Beans (EJB), Oracle, Ajax, iBATIS, Hibernate, Spring, Java
Experience
Dextcloud Low-Code Platform
https://dextcloud.com/A platform that allows creating business applications in a distributed environment with little or no code. I joined that project as the back-end engineer when it started. My primary responsibility was designing and developing the engine for creating and testing business applications.
Sneaker Con
https://sneakercon.com/Sneaker Con is a platform for vendors and buyers that allows users to buy, sell, and trade sneakers. I was the back-end developer and worked on implementing new business features; I also integrated the application with other systems and scaled it to handle thousands of concurrent users.
Goal Setting Platform – Performance Improvement and Back-end New Features
https://goalscape.appIn this project, my main responsibilities revolved around improving the performance and introducing new back-end features to the Java-based Goal Setting Platform. The back-end was developed using technologies such as Spring and GraphQL, and it was integrated with a front-end application. My tasks included optimizing the back-end performance. Additionally, I contributed to the platform by adding several new features, including public projects, Gantt charts, and support for attachments.
Skills
Languages
Java, UML, SQL, Scratch, Java 8, Python, HTML, JavaScript, GraphQL, TypeScript
Frameworks
JUnit, Spring, Spring Boot, TestNG, Hibernate, Apache Camel, iBATIS, Angular, Camel, Selenium, Swagger, AngularJS, JSON Web Tokens (JWT), Apache CXF, Play Framework
Libraries/APIs
JAX-RS, JAXB, JDBC, Commons HttpClient, JAX-WS, REST APIs
Paradigms
REST, Microservices, Continuous Integration (CI), Test-driven Development (TDD), Test Automation, Back-end Architecture, Management
Other
Freelancing, Apache Commons, WebSockets, Liferay, RESTful Microservices, API Integration, Ajax, Amazon API Gateway, Intercom, KSQL, Enterprise Java Beans (EJB), Cloud, Amazon RDS, Back-end Development, SaaS, Cloud Architecture, Programming, Engineering, Finance, APIs, Gantt Charts, Serverless
Tools
Apache Tomcat, Jenkins, JBoss Drools, AWS SDK, IntelliJ IDEA, AWS Simple Notification Service (SNS), Papertrail, BrowserStack, AWS Fargate, AWS IAM, Amazon Elastic Container Service (Amazon ECS)
Platforms
Amazon EC2, Eclipse, AWS Lambda, Google Cloud Platform (GCP), Amazon Web Services (AWS), Oracle, OpenShift, Amazon, Linux, Android
Storage
Elasticsearch, Amazon DynamoDB, Amazon S3 (AWS S3), MySQL, Redshift, MongoDB, PostgreSQL, Databases
Education
2003 - 2007
Master's Degree in Organization Managment
Gdansk University of Technology - Gdansk, Poland
1999 - 2004
Master's Degree in Computer Science
Gdansk University of Technology - Gdansk, Poland
Certifications
NOVEMBER 2023 - PRESENT
AWS Knowledge: Serverless
Amazon Web Services Training and Certification
DECEMBER 2022 - DECEMBER 2025
AWS Certified Solutions Architect – Associate
Amazon Web Services
SEPTEMBER 2022 - SEPTEMBER 2025
AWS Certified Developer – Associate
AWS
APRIL 2009 - PRESENT
Sun Certified Enterprise Architect
Sun Microsystems