TemaBit

C# developer

A job management system for drivers:

• Designed and implemented the foundation of a job management system for drivers based on ASP.NET Core and Telegram, which allowed drivers to work with jobs without creating a specialized and more difficult to implement mobile application.
• Implemented a basic user interface flow subsystem for interacting with the system via a Telegram chat bot.

A system for collecting information from external sources:

• Designed a subsystem to collect data through a set of proxy servers with the ability to rotate and match them. This significantly reduced the number of failed data collection sessions, which, in turn, reduced the likelihood of users not having relevant data to analyze.
• Optimized and unified inefficient data recording in SQL Server, implemented on stored procedures, by replacing it with Entity Framework Core and more efficient processing algorithms (yes, such a paradox). This allowed to reduce the writing time by 2-3 times and increase the speed of receiving new data by end users.
• Implemented configuration management of a distributed monolith in the Production and Test environments using HashiCorp Consul, allowing the application's behavior to be changed quickly without downtime.
• Implemented a full logging system with log events sent to ELK. This significantly reduced the time required to investigate incidents.
• Implemented health monitoring (health check, metrics). This increased awareness of the operational state of the application and allowed faster response to failures.

New version of the system for collecting information from external sources:

• Initiated the implementation of a new version of the application with migration to the cloud (AWS) and using event-driven architecture (SNS and SQS), automatically scaling the number of instances of data collection modules based on the number of jobs.
• I implemented code style conventions, code analysis by syntax analyzers, code review both during local work and CI/CD process, which significantly increased the quality of the code itself and reduced the number of errors in the final product.
• Implemented unit tests and integration tests, which significantly increased the reliability of the system and reduced the number of errors in production.
• Implemented automatic parallelization of the data collection process using TPL Dataflow, which allowed to increase the processing speed by 2-10 times on the same hardware resources, depending on the data source.
• Designed and implemented integration with external data sources on the web with support for retry logic, fault tolerance, etc. (with unified setting of the general policy and the possibility of flexible customization for a particular module), which allowed to significantly increase the stability of the collection process and the amount of collected data.

Visartech

C# developer

A system for processing and filtering incoming phone calls:

• Designed and implemented the server-side foundation for an incoming phone call processing and filtering system based on ASP.NET Core and Azure App Services.
• Implemented integration with Azure Key Vault to securely store application secrets.
• Integrated the app with Twilio for primary management of incoming calls and making outbound calls.
• Engaged SignalR and Azure SignalR Service to interact with the mobile app.

Must2Go

C# developer

Server part of the tourist site (ASP.NET Web API):

• Integrated the app with a banking system, allowing payments to be accepted on the site using that bank's mechanisms.
• Developed the initial version of a new mechanism for presenting the site's home page information without radical changes to the application architecture. This allowed launching the new feature as quickly as possible (with subsequent implementation of a more correct version), which significantly increased the attractiveness of the site from the end users' point of view.

TQM systems

C# developer

An integration platform for data exchange:

• Developed and implemented the architecture of exchange modules (ASP.NET Core) with "1C:Enterprise 8" (several different configurations), "Nova Poshta", "Prom.ua", as well as modules for the logistics company and the main site of the system. This allowed us to add new entities to the module with minimal time consumption.