I am a Senior Java consultant / contractor, with 7+ years of experience , an expert in migration to cloud micro-services.
Aktualisiert am 19.12.2023
Profil
Freiberufler / Selbstständiger
Remote-Arbeit
Verfügbar ab: 19.12.2023
Verfügbar zu: 100%
davon vor Ort: 0%
Java
Java Spring
Kotlin
Java Spring Boot
Micro-Services
Kubernetes
Kafka
SQL-Datenbanken
Non SQL Database
ReactJS
Docker

Einsatzorte

Einsatzorte

Deutschland, Schweiz, Österreich
möglich

Projekte

Projekte

1 year 8 months
2022-11 - now

build a platform for managing freelance-related projects

Senior Java Software Engineer Java 17 Microservices Spring ...
Senior Java Software Engineer
The startup intended to build a platform for managing freelance-related projects, aiming to streamline project management, communication, and collaboration between freelancers and clients. This system had to be highly scalable, secure, and user-friendly, catering to a diverse range of freelancers and clients across various industries. It had to support project bidding and candidate discovery features.
  • Engineered robust APIs and meticulously maintained elevated test coverage by diligently conducting comprehensive unit and integration testing
  • Drastically reduced platform costs by leveraging Google CloudRun capabilities, using a serverless frontend component in order to avoid keeping the service up all the time
Java 17 Microservices Spring Spring Boot Hibernate Liquibase Redis PostgreSQL Postgres Gradle Unit Testing Integration Testing Kubernetes Docker CI/CD
Lance Hub
1 year 1 month
2021-11 - 2022-11

migration of its old platform to a new microservice architecture.

Senior Java Software Engineer Kotlin Java 11 Microservices ...
Senior Java Software Engineer
A telecommunications company struggled with the migration of its old platform to a new microservice architecture. In order to achieve that, a new platform had to be built, including the frontend, backend, and data layer. The next step would be to move the data into the new one, using scripts for fetching, mapping, and inserting the parsed data.
  • Ensured a highly responsive back-end component by designing a microservice environment powered by Spring Boot and Kotlin
  • Achieved a 10x faster communication time between microservices, by using gRPC Remote Procedure Calls instead of REST calls
  • Bumped customer satisfaction by building a new user-friendly interface using React and TypeScript
  • Provided a flexible data layer using MongoDB for the suitable services.


During the transition phase from an old platform to a new one, the client from the telecommunications industry needed a backup solution in case of failure. If something goes wrong, the client should be able to use the old service until a fix is in place. In order to do that, the old data should always be in sync with the newly created one.

  • Ensured 100% synchronization between the old datastore and the new one by having a Kafka queue communicating with a provisioning service, which inserted it into the old data storage
  • Maintained the new platform aware of any failure in the old one, by notifying the operation status through another queue

Kotlin Java 11 Microservices Spring Spring Boot gRPC Hibernate Liquibase MySQL MongoDB Gradle Unit Testing Integration Testing Kubernetes Docker CI/CD React TypeScript Kafka
Sinch
1 year 7 months
2020-05 - 2021-11

Various Projects

Senior Java Software Engineer Java 11 Microservices Spring ...
Senior Java Software Engineer

The client needed an online banking application for legal entities, in order to compete in the banking industry. The app had to accommodate modern features with a user- riendly interface, that would minimize the customer support involvement, while accommodating millions of users.

  • Ensured close to 100% customer satisfaction by adopting an asynchronous approach for long processes, enabling the client to do multiple actions at the same time
  • Drastically reduced application response time, by using Redis distributed cache which minimized interaction with the database layer
  • Reduced audit persistence time to 1/3, by redesigning the application to use a non-relational database solution, like Cassandra.


This banking client required a fast solution for transaction history management. Due to bank politics, each time a transaction takes place, it needs to be stored for an extended period. A slow mechanism for saving transaction history could slow down the entire payment flow and impact customer satisfaction.

  • Improved transaction flow time by 50%, by using a non-relational database solution, in this case Cassandra
  • Dropped read time 10X, by using the database together with a search engine like Solr, capabale of full-text search and real-time indexing.


The bank needed a solution for processing bulk salary payment requests placed by its business clients. It needed to be as user-friendly as possible, enabling the client to load its salary files directly into the platform, minimizing time and human interaction.

  • Achieved a massive increase in customer satisfaction, by building a mechanism for parsing salary excel files uploaded by the clients
  • Enabled the customer to do multiple actions in the app while waiting for the process to finish, by choosing an asynchronous approach for request processing, using message queues
  • Ensured 100% transparency for customers by constantly updating the processing status and by generating an excel result file at the end of the process
Java 11 Microservices Spring Spring Boot Hibernate Liquibase Oracle SQL IBM MQ Gradle Unit Testing Integration Testing Openshift CI/CD Cassandra Solr Redis Unit Testing
Raiffeisen Bank/Luxoft
5 months
2020-01 - 2020-05

migrate graphical tool managing loan rules to upgraded mantainable,scalable web application

Java Software Engineer Java 8 Microservices Spring ...
Java Software Engineer
The banking client wanted to migrate a graphical tool used for managing loan rules to an upgraded mantainable and scalable web application. They concluded that having a license and professionals dedicated to a legacy graphical tool was not financially sustainable. The feasible solution was building an internal service that would accommodate the business needs.
  • Increased scalability 10X, by designing a higly scalable solution using the reactive programming paradigm
  • Drastically reduced development time by 90% for new business flows , due to the flexibility of a high-level programming language instead of a limited graphical one
  • Saved 80% of infrastructure maintenance cost, by discarding an expensive license and its associated consulting costs
Java 8 Microservices Spring Spring Boot RxJava2 MapStruct Oracle SQL Maven Unit Testing Integration Testing TeamCity CI/CD Monitoring
Deutsche Bank/Luxoft
2 years 11 months
2017-03 - 2020-01

e-commerce platform needed a service for assignment management

Java Software Engineer Java Spring Spring Boot ...
Java Software Engineer
The e-commerce platform needed a service for assignment management. These notifications were sent when user assistance was needed and were listed in multiple places in the app. The business team identified the need to centralize them, so a new solution was needed to accommodate a unified assignment logic.
  • Simplified the business logic by creating a common assignment data model
  • Improved the architecture and, as a result, the future development time by 50%, by migrating the old logic from legacy projects to a dedicated microservice
  • Ensured up to 100% application stability, by introducing unit and integration tests to all the business cases
Java Spring Spring Boot Microservices PostgreSQL Maven Unit Testing Integration Testing Docker CI/CD Datadog Monitoring
Tradeshift

Aus- und Weiterbildung

Aus- und Weiterbildung

Graduation 2018

Computer Science

Bachelor of Computer Science

Politehnica University of Bucharest

Position

Position

  • SENIOR JAVA SOFTWARE ENGINEER
  • CONSULTANT
  • CONTRACTOR
  • FREELANCER

Kompetenzen

Kompetenzen

Top-Skills

Java Java Spring Kotlin Java Spring Boot Micro-Services Kubernetes Kafka SQL-Datenbanken Non SQL Database ReactJS Docker

Produkte / Standards / Erfahrungen / Methoden

Profile:

  • I am a Senior Java consultant / contractor / freelancer, with 7+ years of experience, only interested in remote work
  • I use my skills and expertise with passion to design and implement scalable software solutions for worldwide businesses
  • Drop me a message if you think my expertise could help your organization


Skills:

  • Java
  • Spring framework
  • Spring Boot
  • Microservices
  • Jpa, Hibernate
  • SQL
  • Docker
  • Kubernetes
  • Kafka
  • NoSQL
  • Kotlin
  • React

Einsatzorte

Einsatzorte

Deutschland, Schweiz, Österreich
möglich

Projekte

Projekte

1 year 8 months
2022-11 - now

build a platform for managing freelance-related projects

Senior Java Software Engineer Java 17 Microservices Spring ...
Senior Java Software Engineer
The startup intended to build a platform for managing freelance-related projects, aiming to streamline project management, communication, and collaboration between freelancers and clients. This system had to be highly scalable, secure, and user-friendly, catering to a diverse range of freelancers and clients across various industries. It had to support project bidding and candidate discovery features.
  • Engineered robust APIs and meticulously maintained elevated test coverage by diligently conducting comprehensive unit and integration testing
  • Drastically reduced platform costs by leveraging Google CloudRun capabilities, using a serverless frontend component in order to avoid keeping the service up all the time
Java 17 Microservices Spring Spring Boot Hibernate Liquibase Redis PostgreSQL Postgres Gradle Unit Testing Integration Testing Kubernetes Docker CI/CD
Lance Hub
1 year 1 month
2021-11 - 2022-11

migration of its old platform to a new microservice architecture.

Senior Java Software Engineer Kotlin Java 11 Microservices ...
Senior Java Software Engineer
A telecommunications company struggled with the migration of its old platform to a new microservice architecture. In order to achieve that, a new platform had to be built, including the frontend, backend, and data layer. The next step would be to move the data into the new one, using scripts for fetching, mapping, and inserting the parsed data.
  • Ensured a highly responsive back-end component by designing a microservice environment powered by Spring Boot and Kotlin
  • Achieved a 10x faster communication time between microservices, by using gRPC Remote Procedure Calls instead of REST calls
  • Bumped customer satisfaction by building a new user-friendly interface using React and TypeScript
  • Provided a flexible data layer using MongoDB for the suitable services.


During the transition phase from an old platform to a new one, the client from the telecommunications industry needed a backup solution in case of failure. If something goes wrong, the client should be able to use the old service until a fix is in place. In order to do that, the old data should always be in sync with the newly created one.

  • Ensured 100% synchronization between the old datastore and the new one by having a Kafka queue communicating with a provisioning service, which inserted it into the old data storage
  • Maintained the new platform aware of any failure in the old one, by notifying the operation status through another queue

Kotlin Java 11 Microservices Spring Spring Boot gRPC Hibernate Liquibase MySQL MongoDB Gradle Unit Testing Integration Testing Kubernetes Docker CI/CD React TypeScript Kafka
Sinch
1 year 7 months
2020-05 - 2021-11

Various Projects

Senior Java Software Engineer Java 11 Microservices Spring ...
Senior Java Software Engineer

The client needed an online banking application for legal entities, in order to compete in the banking industry. The app had to accommodate modern features with a user- riendly interface, that would minimize the customer support involvement, while accommodating millions of users.

  • Ensured close to 100% customer satisfaction by adopting an asynchronous approach for long processes, enabling the client to do multiple actions at the same time
  • Drastically reduced application response time, by using Redis distributed cache which minimized interaction with the database layer
  • Reduced audit persistence time to 1/3, by redesigning the application to use a non-relational database solution, like Cassandra.


This banking client required a fast solution for transaction history management. Due to bank politics, each time a transaction takes place, it needs to be stored for an extended period. A slow mechanism for saving transaction history could slow down the entire payment flow and impact customer satisfaction.

  • Improved transaction flow time by 50%, by using a non-relational database solution, in this case Cassandra
  • Dropped read time 10X, by using the database together with a search engine like Solr, capabale of full-text search and real-time indexing.


The bank needed a solution for processing bulk salary payment requests placed by its business clients. It needed to be as user-friendly as possible, enabling the client to load its salary files directly into the platform, minimizing time and human interaction.

  • Achieved a massive increase in customer satisfaction, by building a mechanism for parsing salary excel files uploaded by the clients
  • Enabled the customer to do multiple actions in the app while waiting for the process to finish, by choosing an asynchronous approach for request processing, using message queues
  • Ensured 100% transparency for customers by constantly updating the processing status and by generating an excel result file at the end of the process
Java 11 Microservices Spring Spring Boot Hibernate Liquibase Oracle SQL IBM MQ Gradle Unit Testing Integration Testing Openshift CI/CD Cassandra Solr Redis Unit Testing
Raiffeisen Bank/Luxoft
5 months
2020-01 - 2020-05

migrate graphical tool managing loan rules to upgraded mantainable,scalable web application

Java Software Engineer Java 8 Microservices Spring ...
Java Software Engineer
The banking client wanted to migrate a graphical tool used for managing loan rules to an upgraded mantainable and scalable web application. They concluded that having a license and professionals dedicated to a legacy graphical tool was not financially sustainable. The feasible solution was building an internal service that would accommodate the business needs.
  • Increased scalability 10X, by designing a higly scalable solution using the reactive programming paradigm
  • Drastically reduced development time by 90% for new business flows , due to the flexibility of a high-level programming language instead of a limited graphical one
  • Saved 80% of infrastructure maintenance cost, by discarding an expensive license and its associated consulting costs
Java 8 Microservices Spring Spring Boot RxJava2 MapStruct Oracle SQL Maven Unit Testing Integration Testing TeamCity CI/CD Monitoring
Deutsche Bank/Luxoft
2 years 11 months
2017-03 - 2020-01

e-commerce platform needed a service for assignment management

Java Software Engineer Java Spring Spring Boot ...
Java Software Engineer
The e-commerce platform needed a service for assignment management. These notifications were sent when user assistance was needed and were listed in multiple places in the app. The business team identified the need to centralize them, so a new solution was needed to accommodate a unified assignment logic.
  • Simplified the business logic by creating a common assignment data model
  • Improved the architecture and, as a result, the future development time by 50%, by migrating the old logic from legacy projects to a dedicated microservice
  • Ensured up to 100% application stability, by introducing unit and integration tests to all the business cases
Java Spring Spring Boot Microservices PostgreSQL Maven Unit Testing Integration Testing Docker CI/CD Datadog Monitoring
Tradeshift

Aus- und Weiterbildung

Aus- und Weiterbildung

Graduation 2018

Computer Science

Bachelor of Computer Science

Politehnica University of Bucharest

Position

Position

  • SENIOR JAVA SOFTWARE ENGINEER
  • CONSULTANT
  • CONTRACTOR
  • FREELANCER

Kompetenzen

Kompetenzen

Top-Skills

Java Java Spring Kotlin Java Spring Boot Micro-Services Kubernetes Kafka SQL-Datenbanken Non SQL Database ReactJS Docker

Produkte / Standards / Erfahrungen / Methoden

Profile:

  • I am a Senior Java consultant / contractor / freelancer, with 7+ years of experience, only interested in remote work
  • I use my skills and expertise with passion to design and implement scalable software solutions for worldwide businesses
  • Drop me a message if you think my expertise could help your organization


Skills:

  • Java
  • Spring framework
  • Spring Boot
  • Microservices
  • Jpa, Hibernate
  • SQL
  • Docker
  • Kubernetes
  • Kafka
  • NoSQL
  • Kotlin
  • React

Vertrauen Sie auf Randstad

Im Bereich Freelancing
Im Bereich Arbeitnehmerüberlassung / Personalvermittlung

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Rufen Sie uns an +49 89 500316-300 oder schreiben Sie uns:

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