Oleg Sinelnikov - Software Engineer

Q: Where is Oleg based?

Oleg is based in Massa, Italy .

Q: What languages does Oleg speak?

Oleg speaks the following languages: Ukrainian (Native), English (Intermediate), Italian (Elementary) .

Q: How many years of experience does Oleg have?

Oleg has at least 26 years of experience. During this time, Oleg has worked in at least 5 different roles and for 5 different companies . The average length of individual experience is 5 years and 1 month . Note that Oleg may not have shared all experience and actually has more experience.

Q: What is Oleg's latest experience?

Oleg's most recent position is Software Engineer at Tigo Energy, Inc. .

Q: What companies has Oleg worked for in recent years?

In recent years, Oleg has worked for Tigo Energy, Inc. and VData Software-Entwicklung GmbH .

Q: Which industries is Oleg most experienced in?

Oleg is most experienced in industries like Manufacturing , Information Technology (IT) , and Energy . Oleg also has some experience in Biotechnology and Healthcare .

Q: Which business areas is Oleg most experienced in?

Oleg is most experienced in business areas like Procurement and Purchasing , Supply Chain Management , and Information Technology (IT) . Oleg also has some experience in Project Management and Product Development .

Q: Which industries has Oleg worked in recently?

Oleg has recently worked in industries like Energy and Information Technology (IT) .

Q: Which business areas has Oleg worked in recently?

Oleg has recently worked in business areas like Information Technology (IT) , Project Management , and Product Development .

Recommended expert

Massa, Italy

Experience

Aug 2021 - Present

4 years 7 months

Campbell, United States

Software Engineer

Tigo Energy, Inc.

Web application development using Java, Python, PostgreSQL, Docker
Delivery support including CSV, PDF, Excel, tables, charts
Managing Azure DevOps projects: sprints, version control, CI/CD, deployment
Integrating new customers via RESTful APIs, FTP/SFTP

Nov 2019 - Aug 2021

1 year 10 months

Munich, Germany

Java/JS Developer

VData Software-Entwicklung GmbH

Web application development using Java, JavaScript, React JS, MySQL
Served as Scrum Master

May 2016 - Nov 2019

3 years 7 months

Kharkiv, Ukraine

.NET Developer

Freelance

Desktop application development using C#, MS SQL Server, WPF, WinForms, Entity Framework
CRM systems integration

Jul 2001 - May 2016

14 years 11 months

Kharkiv, Ukraine

Supply Manager

Dask-Center

Managed end-to-end furniture parts supply chain operations
Implemented CRM systems
Collaborated with manufacturers, distributors, and vendors

Jul 2000 - Jul 2001

1 year 1 month

Kharkiv, Ukraine

Program Engineer

Kharkiv Medical Genetic Center

Project management
Database development

Predict Plus Project

Tigo Energy, Inc.

Developed and maintained billing systems for managing transactions between customers and power plants, including new feature development and system optimization
Designed application architectures using Java, Spring Boot and other frameworks to build scalable and reliable systems
Integrated various systems and APIs to automate billing processes and payment handling
Developed and integrated monitoring and logging solutions for real-time problem detection and resolution
Improved system performance by optimizing processes
Analyzed client requirements and provided technical solutions
Managed the software development lifecycle including development, testing, deployment, and support

Customer Portal Development

eVorsorge

Developed and customized customer portals, product calculators, online scheduling tools, document upload functions, and campaign management tools
Implemented scalable interfaces, import/export configurators for payroll systems, and APIs for seamless integration
Supported customer data management including contracts, documents, campaigns, and activities
Automated customer interaction for lead generation and personalized user experience
Implemented hierarchical sales and accounting structures with detailed rights and roles management

Industries Experience

See where this freelancer has spent most of their professional time. Longer bars indicate deeper hands-on experience, while shorter ones reflect targeted or project-based work.

Experienced in Manufacturing (15 years), Information Technology (5.5 years), Energy (4.5 years), Biotechnology (1 year), and Healthcare (1 year).

Manufacturing

Information Technology

Energy

Biotechnology

Healthcare

Business Areas Experience

The graph below provides a cumulative view of the freelancer's experience across multiple business areas, calculated from completed and active engagements. It highlights the areas where the freelancer has most frequently contributed to planning, execution, and delivery of business outcomes.

Experienced in Procurement (15 years), Supply Chain Management (15 years), Information Technology (11 years), Project Management (7.5 years), and Product Development (5.5 years).

Procurement

Supply Chain Management

Information Technology

Project Management

Product Development

Summary

Experienced developer specializing in Java and PostgreSQL, with expertise in optimizing performance, building scalable systems, and integrating predictive analytics. Skilled in handling high-load data processing, report generation, and backend development for billing and data-driven solutions

Skills

Backend Development (Java, Spring Boot)
Database Optimization (Postgresql, Mysql)
Predictive Analytics Using Metrics Acquisition
Data Aggregation And Transformation (Large Datasets, Energy Sector)
Performance Optimization For Backend Systems
Configuration Management And Reporting Systems Integration
Developed And Optimized Billing Systems For Managing Transactions Between Customers And Power Plants
Optimized Sql Queries And Jsonb Transformations, Improving System Performance
Built Systems For Aggregating And Processing Energy Data Using Different Time Resolutions
Integrated Predictive Analytics Solutions For Enhanced Data Insights
Developed Robust Configuration Systems For Data Reports And Synchronization
Java 5
Sql 8
Javascript 3
Python 3
C# 3
Java 8, Java 11, Java 13, Java 17
Java Frameworks (Spring Boot, Spring Data, Spring Security, Spring Mvc, Spring Session, Spring Ws, Camel, Elk, Java Mail, Log4j, Slf4j, Drools, Poi, Tomcat, Gson, Jackson, Liquibase, X-stream, Vfs2)
Building Tools (Maven, Gradle, Ant)
Orm Frameworks (Hibernate, Spring Data, Jpa, Criteria Api, Entity Framework)
Db Management Systems (Mysql, Postgresql, Timescale Db, Elastic, Ms Sql, Oracle Db)
Client-server Model Interfaces (Rest, Soap)
Version Control Systems (Git, Svn, Perforce)
Collaborative Version Control (Github, Gitlab, Azure, Bitbucket)
Front-end Tools (Html, Css, Javascript, React, Typescript, Thymeleaf, Jquery)
Project Management Systems (Azure Devops, Jira)
Testing Tools (Junit, Mockito, Postman, Swagger, Selenium)
Software Architect Solutions And Design Patterns (Oop Solid Principles, Aop, Acid Transaction Principles)
Data Transfer Formats/protocols: Xml, Json, Excel, Pdf, Csv, Email, Ftp/sftp
Python (Pandas, Numpy, Requests, Imap Tools)
Os Integration (Docker, Docker-compose, Kubernetes)
Basketball
Photo
Travel

Languages

Ukrainian

Native

English

Intermediate

Italian

Elementary

Education

Sep 1995 - Jun 2000

Kharkiv National University named V.N. Karazin

diploma, radio-physics and electronics (quantum physics, microwaves, lasers) · radio-physics and electronics · Kharkiv, Ukraine

Profile

Created

November 2025

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Frequently asked questions

Do you have questions? Here you can find further information.

Where is Oleg based?

Oleg is based in Massa, Italy.

What languages does Oleg speak?

Oleg speaks the following languages: Ukrainian (Native), English (Intermediate), Italian (Elementary).

How many years of experience does Oleg have?

Oleg has at least 26 years of experience. During this time, Oleg has worked in at least 5 different roles and for 5 different companies. The average length of individual experience is 5 years and 1 month. Note that Oleg may not have shared all experience and actually has more experience.

What roles would Oleg be best suited for?

Based on recent experience, Oleg would be well-suited for roles such as: Software Engineer, Java/JS Developer, .NET Developer.

What is Oleg's latest experience?

Oleg's most recent position is Software Engineer at Tigo Energy, Inc..

What companies has Oleg worked for in recent years?

In recent years, Oleg has worked for Tigo Energy, Inc. and VData Software-Entwicklung GmbH.

Which industries is Oleg most experienced in?

Oleg is most experienced in industries like Manufacturing, Information Technology (IT), and Energy. Oleg also has some experience in Biotechnology and Healthcare.

Which business areas is Oleg most experienced in?

Oleg is most experienced in business areas like Procurement and Purchasing, Supply Chain Management, and Information Technology (IT). Oleg also has some experience in Project Management and Product Development.

Which industries has Oleg worked in recently?

Oleg has recently worked in industries like Energy and Information Technology (IT).

Which business areas has Oleg worked in recently?

Oleg has recently worked in business areas like Information Technology (IT), Project Management, and Product Development.

What is Oleg's education?

Oleg attended Kharkiv National University named V.N. Karazin for radio-physics and electronics.

What is the availability of Oleg?

Oleg is immediately available for suitable projects.

What is the rate of Oleg?

Oleg's rate depends on the specific project requirements. Please use the Meet button on the profile to schedule a meeting and discuss the details.