Pavel Kabir, Developer in Moscow, Russia
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Pavel Kabir

Verified Expert  in Engineering

Full-stack & Mobile Developer

Moscow, Russia
Toptal Member Since
January 5, 2017

Pavel is a business-oriented full-stack software engineer (React, React Native, .NET), architect, and startup CTO. He is a motivated tech universalist capable of building software development companies from scratch and has produced multiple MVPs and high-quality, fully-featured public releases. Pavel excels at engineering, DevOps, business analysis, and QA practices.


SignalR, WebRTC, WebSockets, Jest, REST, OpenAPI, Twilio, Jira, GitLab, Node.js...
Spotware Systems
Layout, Android, iOS, Model View ViewModel (MVVM), Knowledge Management...
LINQ, ANTs, DotTrace, MySQL, NUnit, xUnit, ReSharper, Bitbucket, Stash, Bamboo...




Preferred Environment

Visual Studio Code (VS Code), Git

The most amazing...

...thing I've worked on was a set of white-labeled cross-platform apps in React Native, a shared economy tutoring service improving student lives.

Work Experience

Chief Technology Officer

2018 - PRESENT
  • Hands-on developed and oversaw the full-stack development of a set of cross-platform apps using a cost-effective React/React Native stack with maximum expertise sharing among the team. Architected and delivered features, bug fixes, and Continuous Integration and Deployment (CI/CD) infrastructure.
  • Grew a team of 15 people across two projects; designing job descriptions, interviewing, hiring, and ensuring continuous growth through regular 1–1 meetings and personal mentorship. Implemented Agile and trained the Scrum Master.
  • Established and documented the product management & QA process from the ground up, which included product backlog management, user stories, functional specifications, test cases, verification procedures, end-to-end, and regression testing.
  • Adopted best development practices from day one with feature branching, nit-pick-free code reviews with automatic styling, Test-Driven Development (TDD) with 100% coverage, integration testing, CI/CD using Docker-based pipelines.
  • Championed open source contributions of internal infrastructure.
  • Ensured the accumulation of process, architecture, and style best practices in the internal Knowledge Base.
Technologies: SignalR, WebRTC, WebSockets, Jest, REST, OpenAPI, Twilio, Jira, GitLab, Node.js, Firebase, MongoDB, PostgreSQL, Docker, .NET Core, Redux-Saga, Redux, React Native, React, TypeScript

Software Engineer

2017 - 2018
Spotware Systems
  • Developed features and fixed bugs for a cross-platform, mobile, currency-trading (CFD) app for Android and iOS.
  • Participated in proactive technical debt clearance, code, and architecture improvement initiatives.
  • Wrote numerous solution tests that ensured consistency in the localization of resources, IoC registrations, correct disposal of disposable objects, and common issues in Android layout files.
  • Reduced responsiveness lags and freezes on Android by removing all blocking inter-thread calls from the code.
  • Improved the UI layout time by 25% on a performance-critical Android screen by using flat ConstraintLayout instead of nested LinearLayout hierarchies.
  • Improved the overall performance of an iOS application (up to 10% on some screens) by using one-way MVVM bindings wherever possible.
  • Introduced and managed the .NET team's knowledge base —by writing how-to articles, troubleshooting pages, and providing examples for technical agreements.
  • Distributed monthly digests of new content by email.
Technologies: Layout, Android, iOS, Model View ViewModel (MVVM), Knowledge Management, Code Review, Mockups, Unit Testing, Test-driven Development (TDD), Scrum, Agile, Xamarin, Inversion of Control, .NET, C#

Software Engineer

2015 - 2017
  • Voted 2016's Best Employee of the Financial Module Team.
  • Acknowledged as the top bug fixer on the team.
  • Recognized as the top contributor and manager of the internal developer knowledge base (~50 articles, ~650 edits).
  • Pioneered the unit test coverage of the financial module’s application logic.
  • Implemented numerous performance improvements: delivered linear improvements of up to 85%, as well as slashing quadratic asymptotic complexity to linear.
Technologies: LINQ, ANTs, DotTrace, MySQL, NUnit, xUnit, ReSharper, Bitbucket, Stash, Bamboo, Confluence, Jira, Git, SQL, T-SQL (Transact-SQL), XML, ASP.NET, Microsoft SQL Server, .NET, C#

CEO | Founder

2012 - 2015
Time Island
  • Started and developed an SME wristwatch retail trade business.
  • Created the store concept, design, branding, and positioning from scratch.
  • Worked a great deal on design/marketing outsourcing and maintained an intense line of communication with the freelancers.

iOS Developer

2010 - 2011
  • Developed the first version of In Flow that appeared in the App Store. It was a free app that enabled people to log their moods daily, analyze the patterns, and receive advice on how to feel happier.
  • Participated in client-side development of an independent mobile advertising network.
Technologies: Cocoa, Objective-C, iOS

TEDU App Family

A set of white-labeled cross-platform shared economy tutoring service apps, where students and tutors can connect on campus, Uber-style, to have on-demand sessions with each other. I customized the university designs—the app in the link was made for Florida International University, with "design dressing" process fully automated in a CI pipeline.

Written in React Native, Redux, Redux-Saga, and backed by a RESTful back end over a PostgreSQL database.

This is one of my earlier projects from my school years: a comprehensive mathematical library that's written in C# .NET.

It includes but is not limited to:
• Long integer arithmetic
• Matrix and vector algebra
• A function graph
• An expressions evaluator
• Primality tests
• Pseudo-random number generators
• cryptography including RSA encryption

A cross-platform command line to-do list which is written in C# .NET.

Spotware cTrader
A cross-platform mobile app for FX market trading. It's written in C#.NET using Xamarin.Native.
2013 - 2014

Master's Degree with Honors in Business Analysis

National Research University Higher School of Economics - Moscow, Russia

2013 - 2014

Master's Degree with Honors in E-Business and Innovation

Lancaster University - Lancaster, United Kingdom

2008 - 2012

Bachelor's Degree with Honors in Software Engineering Management

National Research University Higher School of Economics - Moscow, Russia


LINQ, React, Redux-Saga, Styled-jsx, Web API, Node.js, OpenAPI, WebRTC, SignalR


Git, GitLab, Bitbucket, GitLab CI/CD, WebView, Jira, Confluence, Bamboo, Stash, ReSharper, xUnit, DotTrace, ANTs,, Expo, ExpoKit, Mocha


Redux, React Native, .NET, Jest, ASP.NET, .NET Core, NUnit, Cocoa


JavaScript, C#, TypeScript, SQL, CSS, HTML, XML, T-SQL (Transact-SQL), Objective-C, Solidity, PHP, GraphQL


Agile, Management, Continuous Integration (CI), Continuous Delivery (CD), Agile Product Management, Mobile Development, Functional Programming, REST, Scrum, Inversion of Control, Test-driven Development (TDD), Unit Testing, Model View ViewModel (MVVM), App Development


Xamarin, iOS, Android, MvvmCross, Windows, Docker, Linux, Web, DigitalOcean, Visual Studio Code (VS Code), Twilio, Amazon Web Services (AWS), Blockchain, Firebase


Microsoft SQL Server, MySQL, SQL Server Management Studio (SSMS), MongoDB, PostgreSQL


Algorithms, Data Structures, CTO, Analysis, Technical Product Management, Minimum Viable Product (MVP), Mobile App Development, Architecture, People Management, Full-stack, Google Play Store, App Store, APIs, Mockups, Code Review, Knowledge Management, Layout, Machine Learning, Styled-components, WebSockets

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