Mary Mirzoyan, Developer in Berlin, Germany
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Mary Mirzoyan

Verified Expert  in Engineering

Data Modeling Developer

Location
Berlin, Germany
Toptal Member Since
June 18, 2020

Mary's motto in work is "Always deliver more than expected"—this slogan has worked for her throughout her seven-year career path. She loves seeing the magic of technology at work, bringing it to people, and making their lives easier. As a BI developer at Toptal, Mary is here to transform your data into an in-depth visualization to help your business grow.

Portfolio

Bonify
Java, MongoDB, Spring Boot, Hibernate, Databricks, Apache Kafka...
Zenjob GmbH
PostgreSQL, Spring Boot, Java, Groovy, Apache Kafka, JOOQ...
SFL
Docker, MySQL, PostgreSQL, Oracle, Spring Boot, Hibernate, Spring, Java, .NET...

Experience

Availability

Part-time

Preferred Environment

PL/SQL, Oracle, Microsoft SQL Server, PostgreSQL, SQL

The most amazing...

...project I've contributed to was subscriber "churn analysis." By analyzing past churner behavior, we predicted and prevented future churns.

Work Experience

B2B Team Lead

2021 - PRESENT
Bonify
  • Led many feature implementations, process improvements, and became a core member of the team In a very short time.
  • Drove the initiative of storing and analyzing more data for the users and processes, which allowed us better prioritize the feature backlog and come up with new KPIs and features.
  • Engaged in the technical redesign of the main back-end service, which allowed us to decrease the application response times for the REST endpoints and reduce the code complexity and increase the test coverage.
  • Analyzed application funnel combined with more data from different sources and came up with the KPIs for the upcoming quarters to increase the success metrics of our product.
Technologies: Java, MongoDB, Spring Boot, Hibernate, Databricks, Apache Kafka, Reactive Programming, Microsoft Excel, Spring Security, Docker, Amazon Web Services (AWS), Data Modeling, Database Modeling, Data Architecture, REST APIs, SQL, Data Analysis, Analytics, GitHub, Amazon S3 (AWS S3), Data Analytics, Data Visualization, Mixpanel, Data Lakes, Serverless, Communication, Databases, APIs, Google Forms, Excel Reporting, Excel 2016, Google Sheets, Dashboards, Data-driven Dashboards, Finance, Banking & Finance

Senior Back-end Developer

2019 - 2021
Zenjob GmbH
  • Designed and developed innovative solutions and mplemented industry best practices and code reviews.
  • Contributed to all phases of software design, from architecture to testing and monitoring.
  • Provided continuous delivery of the product within Agile methodology.
  • Engaged in setting and supervising the company's KPIs.
  • Set up a process of analyzing data for feature set prioritization. Handled complex data processing and modeling.
  • Engaged in breaking down a monolith system into microservices.
Technologies: PostgreSQL, Spring Boot, Java, Groovy, Apache Kafka, JOOQ, Database Architecture, Microsoft Excel, Hibernate, Spring Security, Docker, Amazon Web Services (AWS), Data Modeling, Database Modeling, Data Architecture, REST APIs, SQL, Data Analysis, Analytics, GitHub, Database Design, Database Schema Design, Amazon S3 (AWS S3), Data Analytics, Data Visualization, Communication, Databases, APIs, Google Forms, Excel 2016, Google Sheets, Dashboards, Data-driven Dashboards

Back-end Engineer

2015 - 2019
SFL
  • Participated in all phases of the software development lifecycle and produced and maintained clean, high-quality code. Delivered results within the Agile methodology, reviewed code, and implemented software development best practices.
  • Designed database architecture. Implemented stored procedures and functions.
  • Engaged in third-party product selection and integration into the existing ecosystem.
Technologies: Docker, MySQL, PostgreSQL, Oracle, Spring Boot, Hibernate, Spring, Java, .NET, C#, Entity Framework, Flyway, Database Architecture, Microsoft Excel, Spring Security, ADO.NET, ASP.NET, LINQ, Oracle 10g, MVC Frameworks, Data Modeling, Database Modeling, Data Architecture, REST APIs, SQL, GitHub, Database Design, Database Schema Design, Data Visualization, Oracle PL/SQL, Communication, Databases, APIs, Data Aggregation, Google Sheets, Excel 2010, Finance, Banking & Finance

.NET Software Engineer

2012 - 2018
Comine-Soft
  • Designed and developed MVC web and windows desktop applications for health organizations.
  • Created the database architecture and implemented all data manipulations in the database (views, functions, procedures, jobs, etc.).
  • Implemented embedded and ad-hoc analytical reports for the clients.
Technologies: T-SQL (Transact-SQL), Microsoft SQL Server, LINQ, VB, C#, ADO.NET, ASP.NET, ASP.NET MVC, Database Architecture, Microsoft Excel, .NET, MVC Frameworks, Data Modeling, Database Modeling, Reporting, Reports, Business Intelligence (BI), Data Architecture, SQL, Data Analysis, Analytics, Database Design, Database Schema Design, Data Analytics, Data Visualization, SQL Server 2012, Communication, Databases, APIs, Data Aggregation, Data Reporting, Excel 2010

BI Reporting Analyst

2012 - 2015
MTS Armenia
  • Designed and maintained the data warehouse and created KPIs and dimensions (standard, slowly changing). Developed fact tables and data aggregation.
  • Manipulated data with ETL tools (particularly SSIS) and built OLAP cubes (SSAS).
  • Created scheduled (SSRS) and ad-hoc reports mainly for management and marketing.
  • Developed the data visualization via Power Pivot and Microsoft Excel for the stakeholders.
  • Participated in many projects for customer segmentation, evaluation, and creditworthiness calculation.
Technologies: Power Pivot, Microsoft Excel, SSAS, SQL Server Integration Services (SSIS), SQL Server Reporting Services (SSRS), PL/SQL, Oracle 10g, T-SQL (Transact-SQL), Microsoft SQL Server, Database Architecture, Data Engineering, Microsoft Power BI, ETL, Data Warehousing, Data Warehouse Design, Slowly Changing Dimensions (SCD), Data Modeling, Database Modeling, Reporting, Reports, Business Intelligence (BI), Data Architecture, SQL, Data Analysis, Analytics, Database Design, Database Schema Design, Data Analytics, Data Visualization, Snowflake, Oracle PL/SQL, SQL Server 2012, Communication, Databases, Data Aggregation, Excel Reporting, Excel 2016, Dashboards, Data-driven Dashboards, Data Reporting, Excel 2010, BI Reporting

Customer Segmentation Project

Working at MTS Armenia, the largest telecommunication operator in Armenia, there was a need for some customer segmentation. All active (within the past three months) customers had to be included in some predefined segments according to their activity, generated amount, suspensions, and other factors. The main reason for this project was to ensure better service (mainly call center) for "better" customers. The goal was achieved using multiple sources, ETL tools, and monthly aggregations and jobs. The end-product was also integrated with the call center application.

Customer Satisfaction Project

When working in telecom, I participated in a customer satisfaction project implementation. The first step was to collect and save all customer information from different sources like service centers, call centers, and the complaint system. The second step included automated calls to the customer and collecting their rates on particular predefined questions about service quality. And finally, there was a need for different data visualization reports for quality assurance staff for a deeper insight.

Customer Scoring Project

The most popular telecom operator in Armenia, MTS-Armenia, was selling accessories in their service center and increasing their income and customer base; they decided to sell the phones with joint monthly subscription plans in a loan model, with monthly payments. And because there was a need to evaluate the risks for each customer, we designed and implemented a customer scoring project. According to the flow, some previous loan history was requested. If the customer met the necessary criteria, they were analyzed as our subscribers (how often they had been suspended, their monthly generated value, risk that they wouldn't pay the debt, etc.). The system successfully went live in a few months with a low probability of default rate.

Hibernate to MySQL Procedures Transformation

My client needed to transform their existing hibernate calls in the groovy-based application to stored procedures in the MySQL database. I have evaluated and estimated the work and correspondingly implemented the necessary stored procedures by analyzing the existing groovy code. The main challenge of the project was the time constraint, but the project was successfully finished and tested before the deadline.

Languages

SQL, T-SQL (Transact-SQL), Groovy, Java, C#, VB, Snowflake

Libraries/APIs

REST APIs, LINQ, JOOQ, Entity Framework

Tools

Microsoft Excel, Power Pivot, GitHub, Excel 2016, Google Sheets, Excel 2010, Microsoft Power BI, SSAS, Google Forms, Flyway

Paradigms

Business Intelligence (BI), Database Design, ETL, Reactive Programming

Storage

Microsoft SQL Server, PL/SQL, PostgreSQL, MySQL, SQL Server 2012, Databases, Database Architecture, SQL Server Integration Services (SSIS), Database Modeling, MongoDB, Amazon S3 (AWS S3), Oracle PL/SQL, Oracle 10g, SQL Server Reporting Services (SSRS), Data Lakes

Other

Data Architecture, Database Schema Design, Data Analytics, Data Visualization, Communication, APIs, Data Aggregation, Excel Reporting, Data Reporting, Data Engineering, MVC Frameworks, Data Warehousing, Data Warehouse Design, Slowly Changing Dimensions (SCD), Data Modeling, Reporting, Reports, Data Analysis, Analytics, Dashboards, Data-driven Dashboards, BI Reporting, Finance, ETL Tools, Serverless

Frameworks

Spring Boot, Spring Security, Spring, Hibernate, ASP.NET MVC, .NET, ADO.NET, ASP.NET

Platforms

Oracle, Amazon Web Services (AWS), Docker, Databricks, Apache Kafka, Mixpanel

Industry Expertise

Banking & Finance

2012 - 2014

Master's Degree in Informatics and Applied Mathematics

Yerevan State University - Yerevan, Armenia

2008 - 2012

Bachelor's Degree in Informatics and Applied Mathematics

Yerevan State University - Yerevan, Armenia

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