Bidmind by Fiksu is a Demand Side Platform with Real Time Bidding to show advertisement in Web, Mobile, Desktop, and CTV applications. Company uses accurate real-time machine learning models to win in real-time price auction in successful and profitable way. Model is based on user’s device type, platform, browser, location, time, interests, previous activities and etc. Response time restriction is 100 ms. Distribution over the world. Hundreds of thousands of auctions per second. Hundreds of terabytes of data for machine learning and aggregated real-time reports. There are also various user audiences build on sophisticated algorithms. System incrementally actualises billions of mobile profiles. My responsibilities: Developed, optimised Scala ETL Apache Spark flows to extract, transform, validate, enrich, join, aggregate data for reporting, analysing, investigation, uploading to warehouse and machine learning model usage. Implemented Apache Zeppelin notebooks for reporting and analysing. Supported Apache Spark meta catalog to query parquet Amazon S3 data with SQL. Supported Clickhouse warehouse: optimise queries, configure, pre -aggregated cube building with dimensions and measures. Developed different Apache Kafka data collectors, Kafka Streams applications for audience/mobile profiles. Designed and developed Apache Kafka Streams scraper to collect application data from different app stores (Google Play, Apple and etc) and to gather authorised advertisers data located on developer domains. Developed Federated Warehouse based on Apache Calcite to have single SQL entry point with querying data from different DB, S3 and other sources. Added optimisation rules. Design: different technologies and data investigation to choose right architecture, integration. Support: optimisation tasks, bug fix, monitoring Grafana charts, feature production deployment, cluster scaling, alerts monitoring, Kibana logs analysing, Kubernetes yaml Docker files set-up, code reviews.

SWISSQUOTE BANK is Switzerland’s leading provider of online financial and trading services.A huge currency quotes stream are received from quotes exchanges. System builds own synthetic quotes and translates to customers to be buy or sell. The system based on Akka framework is high load, low latency, resilient and scalable. There are also cryptocurrency stream based on JMS that is used by Web Services and React client for trading. In my position: - Implement new and extend existing Akka concurrency flows for trading FOREX platform; - Bug fixing; - Design: discuss external system API, propose problem solutions. - Optimisation tasks. - Designed and developed from scratch with other tech leaders data access framework to serialise, store, read and deserialise any java object to/from HBase with custom DSL.

FIM DEUTSCHE BANK. ETL batch Apache Hadoop system that extracts data from different sources, validates, transforms, enriches and uploads it to warehouse. My responsibilities: - Implement Apache Hadoop maps/reducer tasks, java tasks, Oozie flows, XSLT transformations. - Develop code to import data from various upstreams, XML enrichment, filtering, various data checks, XSD validation. - Bug fix. - Design: match Technical documents and functional specifications; discuss problems, propose solutions; discuss APIs. - Code reviews. - Implement optimisation tasks; - Developed and designed Hive “record fetcher” with xml serve, to read XML sequence files from HDFS. - Designed hive meta data generator for DDL scripts according XSD schemas. - Designed and developed feed notification generator for generating scripts to run jobs for appropriate feeds.

HOME CREDIT BANK.Company serves HOME CREDIT BANK system. All over the country credit consultants fills consumer loan requests and sends them to core services. Credit requests are went through agreement flows with different scoring and manual checks. Flow and Checks are selected by request and bank criteria. System uses web client, web services and Oracle database. My responsibilities: - Develop business tasks. - Design: discuss APIs, problems, solutions in meetings; approve functional specifications written by analysts; write technical specifications. - Code review. - Optimisation tasks. - developed «DB Template» web application, which create and clone Oracle DB for testing scripts. - Jasper Report.