David is available for hire

David Sumegi

Verified Expert in Engineering

Software Developer

Location

Budapest, Hungary

Toptal Member Since

January 5, 2021

Backed by several years of hands-on experience, David is a software developer who excels at building Java back-end services, relational databases, and software architecture. His solid testing background makes him the type of developer who prevents incidents early on via automated tests with 100% code coverage. David is also an enthusiast of SOLID principles, clean code, clean architecture, and design patterns.

API Design Back-end Test-driven Development (TDD)Unit Testing JSON RDBMS Java 8 Java REST APIs JDBC Spring JDBC JDK 8 MySQL Web Services SQL Java 11 Relational Databases

Portfolio

FedEx

Java, Java 17, Spring WebFlux, Reactor, Spring, PostgreSQL, Jackson, Lombok

SwissRe iptiQ - Main

Java, Spring, Message Queues, SOLID Principles, NoSQL

Latch

Java, Java 8, MongoDB, Databases, REST APIs, Datadog, Play Framework, Git...

Experience

SQL - 7 years RESTful Development - 6 years Microservices - 6 years Git - 6 years Spring Boot - 6 years Spring - 6 years Java - 6 years Java 11 - 2 years

Availability

Part-time

Preferred Environment

Apache Maven, Spring, SQL, Git, Java

The most amazing...

...project in 2020 developing the back-end integration of Hungary's first fully online 24/7 solution for retail customers to open a bank account for free.

Work Experience

Back-end Developer

2022 - PRESENT

FedEx

Added eCommerce capabilities to the shipment management system.
Implemented an API integration to an external aggregation service and eCommerce platforms.
Participated in architectural changes, like splitting a monolith service into microservices.

Technologies: Java, Java 17, Spring WebFlux, Reactor, Spring, PostgreSQL, Jackson, Lombok

Java Developer

2021 - 2021

SwissRe iptiQ - Main

Prepared back-end services for an upcoming migration to a different platform provider.
Collected and analyzed information to determine data models for the conversion of migrated data.
Supported data analysts by generating schema files.

Technologies: Java, Spring, Message Queues, SOLID Principles, NoSQL

Software Contractor

2021 - 2021

Latch

Refactored and extended middleware functions syncing property and resident information from external property management systems.
Increased observability of back-end processes by adding Datadog metrics and monitors to service and daemon applications.
Created detailed documentation on the existing business logic as well as the new features.

Technologies: Java, Java 8, MongoDB, Databases, REST APIs, Datadog, Play Framework, Git, Bitbucket, Jira, Confluence, Refactoring, Amazon CloudWatch, IntelliJ IDEA, Terraform, Terragrunt, Google Guice, Spring, Information Technology, Back-end, Software Implementation, Gradle, Amazon Web Services (AWS), JUnit, RDBMS, RESTful Services

Senior Back-end Developer

2019 - 2021

Bankmonitor

Introduced new calculators to Bankmonitor's market-leading independent public website comparing banking services.
Migrated Java 8 monolith services to scalable Spring Boot microservices using Java 11 running on Amazon Elastic Kubernetes Service.
Optimized the performance of back-end systems to minimize response times and handle an increasing load of requests.

Technologies: Back-end, Clean Architecture, JSON, Eclipse IDE, Unit Testing, Software Implementation, Test-driven Development (TDD), Object-oriented Programming (OOP), Lombok, Java SE 8, API Design, RESTful Microservices, Jenkins, Spring 5, Spring 4, JDK 8, Java SE, Spring JDBC, JDBC, APIs, REST, REST APIs, Web Services, Architecture, Clean Code, Spring IoC, Design Patterns, Software Architecture, Spring Security, Apache Maven, MySQL, SQL, Relational Databases, Git, RESTful Development, Microservices, Spring Boot, Spring, Java 11, Java 8, Vaadin, Information Technology, Refactoring, Jira, Bitbucket, Databases, Fintech, Amazon Web Services (AWS), Microservices Architecture, JUnit, RDBMS, RESTful Services, Hibernate

Java Developer

2020 - 2020

Mana Monitoring

Established synchronization between MySQL and Apache Cassandra databases storing solar energy billing information.
Created a bill uploading and parsing function with a web user interface for clients.
Implemented a reporting tool collecting and comparing billing data originating from different sources for the same site.

Technologies: Back-end, Clean Architecture, JSON, Eclipse IDE, Unit Testing, Software Implementation, Test-driven Development (TDD), Object-oriented Programming (OOP), Lombok, Spring 5, JDK 8, Spring JDBC, JDBC, Architecture, Software Architecture, Design Patterns, Spring IoC, Clean Code, API Design, RESTful Microservices, Microservices, Jenkins, Apache Maven, GitLab, Git, Spring, Spring Boot, Java SE 8, Java SE, SQL, MySQL, Relational Databases, Web Services, RESTful Development, REST APIs, REST, APIs, Java 8, Java, Information Technology, Jira, Databases, JUnit, RDBMS, RESTful Services

Java Web Developer

2017 - 2019

BlackRock

Built a new web-based version of an old portfolio management application while cooperating closely with front-end developers and key users.
Integrated artificial intelligence into the existing document management system while working with machine learning and NLP experts.
Acted as a lead developer within the local sub-team of developers and data scientists.

Technologies: Back-end, Clean Architecture, Sybase, JSON, Eclipse IDE, Unit Testing, Software Implementation, Test-driven Development (TDD), Object-oriented Programming (OOP), Lombok, Java SE 8, API Design, RESTful Microservices, Jenkins, Spring 5, Spring 4, JDK 8, Java SE, Spring Aspect-oriented Programming (AOP), Spring AOP, Spring JDBC, JDBC, Hibernate, Spring Data, APIs, REST, REST APIs, Web Services, Architecture, Software Architecture, Design Patterns, Clean Code, Spring IoC, Spring Security, Unix Shell Scripting, Java, Apache Maven, SQL, Relational Databases, Git, Spring Boot, Spring, RESTful Development, Microservices, Java 8, Information Technology, Jira, Bitbucket, Databases, IntelliJ IDEA, Fintech, Microservices Architecture, JUnit, RDBMS, RESTful Services

Software Developer

2014 - 2017

Morgan Stanley

Upgraded legacy stock loan management systems with modern microservices.
Added search and cache layers to systems that were tracking financial transactions.
Improved data access performance by optimizing database queries and configurations.

Technologies: Back-end, Clean Architecture, IBM Db2, Sybase, JSON, Eclipse IDE, Unit Testing, Software Implementation, Test-driven Development (TDD), Object-oriented Programming (OOP), Lombok, Java SE 8, API Design, RESTful Microservices, Jenkins, Spring 4, JDK 8, Java SE, Spring JDBC, JDBC, APIs, REST, REST APIs, Web Services, Architecture, Software Architecture, Design Patterns, Clean Code, Spring IoC, Spring Security, Unix Shell Scripting, Java, Apache Maven, Microservices, RESTful Development, SQL, Relational Databases, Spring Boot, Spring, Git, Java 8, Information Technology, Jira, Databases, IntelliJ IDEA, Fintech, Microservices Architecture, JUnit, RDBMS, RESTful Services, Hibernate

Senior Test Automation Engineer

2013 - 2014

NNG

Built an automation framework for testing navigation systems of Fiat, Ferrari, and Toyota cars.
Implemented nightly jobs to receive and validate operating system updates sent by Harman.
Defined standard processes for project management to track validation requirements and release results.

Technologies: JSON, Unit Testing, Software Implementation, Test-driven Development (TDD), Object-oriented Programming (OOP), Unix Shell Scripting, HTML, Relational Databases, MySQL, SQL, Test Automation Frameworks, Information Technology, Databases, RDBMS

System Test Engineer

2011 - 2013

Bosch

Built test plans for the next-generation video-based driver assistance systems of Audi, Porsche, and Volkswagen cars.
Automated 98% of manual test sets for selected areas of image detection functions.
Designed and deployed a visual simulation tool using a controllable OLED display to support lab testing of camera features.

Technologies: Test Automation Frameworks, Information Technology

Software Engineer

2007 - 2010

Nokia Siemens Networks

Started as a university student composing my thesis on software test automation principles and techniques.
Fixed bugs and extended regression test suites continuously to prevent incidents.
Implemented new methods inside the test automation framework using Perl scripts.

Technologies: Test Automation Frameworks, Information Technology

Experience

Online E2E Contracting for Bank Customers (CIB)

https://www.bankmonitor.hu/

Worked as the back-end engineer on this project in cooperation with Bankmonitor—Hungary's market-leading independent online bank product broker— and CIB to enable retail customers to open a new bank account anytime without speaking with a dispatcher.

My tasks involved the API integration of several systems, including a third-party video authentication provider. I covered the whole software lifecycle, from analyzing the business requirements to deployment and end-user support.

Aladdin Document Repository (BlackRock)

Added automatic OCR and metadata cleansing functions to an existing document management system. Furthermore, I extended the repository with an AI feature created by data scientists that used natural language processing to extract specific data from the files' text content.

eCommerce Capabilities Project for FedEx

http://www.fedex.com

Participated in a project that enables eCommerce merchants to connect their stores with the FedEx shipment management system so that they import their orders and have all shipment information filled automatically,

Education

2002 - 2008

Master's Degree in Electrical Engineering

Budapest University of Technology and Economics (BME) - Budapest, Hungary

Skills

Languages

Java 8, Java, Java SE, Java SE 8, Java 11, SQL, HTML

Frameworks

Spring JDBC, Spring, Spring Boot, Spring Security, Spring IoC, Hibernate, Spring 4, Spring 5, Vaadin, JUnit, Spring AOP, Play Framework, Google Guice

Libraries/APIs

REST APIs, JDBC, Lombok, Terragrunt, Reactor, Jackson

Tools

JDK 8, Git, Eclipse IDE, Apache Maven, GitLab, Jenkins, Bitbucket, Jira, Confluence, Amazon CloudWatch, IntelliJ IDEA, Terraform, Gradle

Paradigms

REST, Object-oriented Programming (OOP), Test-driven Development (TDD), Unit Testing, Clean Architecture, RESTful Development, Microservices, Design Patterns, Clean Code, Microservices Architecture, Spring Aspect-oriented Programming (AOP), Refactoring

Storage

MySQL, JSON, RDBMS, Relational Databases, Sybase, Spring Data, IBM Db2, MongoDB, Databases, Datadog, Redis, NoSQL, PostgreSQL

Other

Test Automation Frameworks, APIs, Architecture, Software Architecture, API Design, Software Implementation, Back-end, Fintech, RESTful Services, Web Services, RESTful Microservices, Information Technology, Unix Shell Scripting, Message Queues, SOLID Principles, Java 17, Spring WebFlux

Platforms

Amazon Web Services (AWS)

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