Design and implement a cloud data platform for batch and streaming data processing.

Implementing Chatbot providing information about various businesses. We used different customizations for various endpoints - Facebook Messenger, Twitter and Amazon Alexa.Technologies: Java, Spring Boot, Gradle, Amazon AWS (Beanstalk, S3, Kinesis Firehose), Dialogflow (former Api.ai), ELK stack, Docker

Implementing a machine learning pipeline predicting time needed for obtaining an answer to a specific Stack Overflow question. The data set size was 60+ GB and was processed in a distributed manner using Apache Spark 2.1 running on Amazon EMR cluster. Different classification and regression algorithms were evaluated (random forest, support vector machines, naive bayes, logistic/linear regression etc.)Technologies: Scala, Apache Spark (SQL, MLLib), Amazon AWS EMR, S3

Upgrade bank’s back-office frontend application – rewriting a legacy application for bank operators (couple hundreds of concurrent users) and replace the underlying service calls (RPC) with SOA.Responsibilities: Software development and maintenanceTools & technologies used: Weblogic, Java 1.7, Apache Beheeve, JSP, JAX-WS, Ant, Maven, Gradle, Enterprise Architect, SVN

Improving software delivery pipeline for bank – designing and implementing a process of handling software artifacts for one of the biggest Polish banks. A task was realized as an internal Artifactory plugin. Realization of the project led to reward for obtaining a second place in PMI 2016 contest.Responsibilities: Architecture design, process modelling, implementation, project documentation, contact with the customer.Tools & technologies used: Groovy, Artifactory, Bash, Docker… Show more Improving software delivery pipeline for bank – designing and implementing a process of handling software artifacts for one of the biggest Polish banks. A task was realized as an internal Artifactory plugin. Realization of the project led to reward for obtaining a second place in PMI 2016 contest.Responsibilities: Architecture design, process modelling, implementation, project documentation, contact with the customer.Tools & technologies used: Groovy, Artifactory, Bash, Docker, IBM UrbanCode, Jenkins, REST, BPMN 2, GIT Show less

Projects dashboard – architectural design of a system presenting live metrics from ongoing company’s projects. The system was divided into 2 independent subsystems – backend and frontend. There was a pluggable solution for performing online modifications for data being collected. Fronted made use of Redux variation – Vuex for managing state.Responsibilities: Choosing technology stack, system architecture, implementationTools & technologies used:Backend: Java 1.8, Spring Web… Show more Projects dashboard – architectural design of a system presenting live metrics from ongoing company’s projects. The system was divided into 2 independent subsystems – backend and frontend. There was a pluggable solution for performing online modifications for data being collected. Fronted made use of Redux variation – Vuex for managing state.Responsibilities: Choosing technology stack, system architecture, implementationTools & technologies used:Backend: Java 1.8, Spring Web MVC, MongoDB, GradleFrontend: Node.js, Vue.js, Vuex, Webpack, HTML5, SCSSInfrastructure: Docker, Gitlab, Bash Show less

Data migration – concept and implementation of data migration strategy between two customer’s core task management systems (about 30GB of data). Data needed to be migrated as quick as possible to prevent losses. A task was realized with exchanging data on customer’s machine using REST protocol and Spring Batch mechanisms.Responsibilities: Architecture and solution concept, implementationTools & technologies used: Java 1.8, Spring Batch, REST, Docker, Bash, PostgreSQL

Logistic platform - web-application for managing worldwide marine, rail and road deliveries. The application provides very complex security access (various roles and contexts).Responsibilities: Choosing technology stack and architecture, technical leadership (team of 6 developers), assuring code quality (CI/CD) with various metrics, mentored junior programmers, code development.Tools & technologies used: Java 1.8, Spring Framework, Spring Data, Bamboo, JAX-WS, GIT, Apache… Show more Logistic platform - web-application for managing worldwide marine, rail and road deliveries. The application provides very complex security access (various roles and contexts).Responsibilities: Choosing technology stack and architecture, technical leadership (team of 6 developers), assuring code quality (CI/CD) with various metrics, mentored junior programmers, code development.Tools & technologies used: Java 1.8, Spring Framework, Spring Data, Bamboo, JAX-WS, GIT, Apache Tomcat, Wildfly, Bash, HTML, CSS Show less

Secret Client – implementation and maintenance of a system working in an area of secret store audits. The challenges here were the number of users using the system, complex access control, audit reports (both static and dynamic) and periodic task evaluation.Responsibilities: Software development and maintenance, contact with the customerTools & technologies used: Java 1.6, Apache Struts, Jasper Reports, Hibernate, MySQL, Apache Tomcat

European Ski Resorts Data Analysis – implementation of fully autonomous system collecting various data related to European ski resorts (temperature, snow levels, a percentage of open slopes, mentions in social media, fuel prices etc.) in real-time. Measurements were presented using interactive dashboards (Kibana). Later many business hypotheses were formed and validated.Responsibilities: Design and implementation of custom web-crawler, data visualization, interactive dashboards… Show more European Ski Resorts Data Analysis – implementation of fully autonomous system collecting various data related to European ski resorts (temperature, snow levels, a percentage of open slopes, mentions in social media, fuel prices etc.) in real-time. Measurements were presented using interactive dashboards (Kibana). Later many business hypotheses were formed and validated.Responsibilities: Design and implementation of custom web-crawler, data visualization, interactive dashboards, generating custom reports, hypothesis testing.Tools & technologies used: Groovy, Python, Docker, Elasticsearch, Kibana, Gradle, Numpy, Pandas, Bash, Jupyter Notebooks Show less

Call Center System - A plan was to modernize a legacy system (PHP) and partially rewrite in Java technology stack (using IBM solutions). The main requirement was to handle concurrent work of thousands of operators performing calls. The application is supporting the biggest central-European call-center.Responsibilities: Software maintenance and developmentTools & technologies used: PHP, IBM WebSphere, Java EE6, Symphony 1.4, MySQL, MongoDB, IBM DB2, Jenkins, Html/CSS

Application purpose was to gain quick insights about the current state of open tasks in the organization. Main challenges were related to data synchronization issues.Responsibilities: Maintain and develop new features for internal task management app.Tools & technologies used: Eclipse, Android 2.3+, SQLite, TortoiseHg