Mosabbir is available for hire
Hire MosabbirMosabbir Khan Shiblu
Verified Expert in Engineering
Mobile App Developer
Calgary, AB, Canada
Toptal member since July 18, 2017
Bio
With eight years of proven expertise in cross-platform mobile application development in Xamarin.Forms /.NET MAUI, Mosabbir is your go-to developer for any mobile application project. With an additional three years in software engineering research, he is also suitable for R&D work. Mosabbir's portfolio is rich with over 40 professional projects, including 10 Xamarin.Forms and four .NET MAUI projects.
Portfolio
UFA
Xamarin, .NET MAUI
PepsiCo
C#, .NET, Xamarin, XAML, .NET 8, .NET 7, .NET MAUI, Android, iOS, SQL
Zibrio
Xamarin, Cross-platform, Angular, Cloud, AWS IAM, HIPAA Compliance...
Experience
- C# - 8 years
- Cross-platform - 8 years
- Mobile App Development - 8 years
- Mobile Applications - 8 years
- Xamarin.Forms - 6 years
- Xamarin - 6 years
- .NET MAUI - 4 years
- Transact-SQL (T-SQL) - 2 years
Work Experience
.NET MAUI Developer (Contract)
2024 - PRESENT
UFA
- Worked with the Cardlock MAUI app, which allows truck drivers to pay and view transactions.
- Improved gas station location search by name and speed by 1000x using a custom data structure and algorithm.
- Introduced enterprise application design pattern, resulting in increased productivity: https://apps.apple.com/us/app/ufa/id6502371508.
Technologies: Xamarin, .NET MAUI
.NET MAUI Migration Specialist
2023 - 2024
PepsiCo
- Led in-house developers and QA engineers in migrating mission-critical applications to .NET MAUI. The applications are used by hundreds of thousands of employees distributed worldwide.
- Fixed .NET 7 and .NET 8 MAUI memory leak issues caused by framework bugs.
- Reduced data sync time from 30 to 20 minutes as part of migration.
- Refactored various parts of the projects to accommodate future feature integrations.
- Removed unnecessary data allocations during API response processing by streaming to JSON instead of converting to intermediate string.
- Followed Agile principles such as daily stand-ups and distributed work properly among developers and testers.
Technologies: C#, .NET, Xamarin, XAML, .NET 8, .NET 7, .NET MAUI, Android, iOS, SQL
Development Lead
2021 - 2023
Zibrio
- Led a small development team consisting of a product owner, QA, a senior developer, and a junior developer. Introduced agile methodologies.
- Archived HIPAA compliance by properly enabling client-side encryption and storage of PI data.
- Introduced the MVVM pattern and created a ViewModel first navigation service from scratch.
- Developed 3+ Angular libraries for the admin dashboard.
- Enabled the payment system through iOS and Android stores.
- Structured the existing private cloud system to efficiently gather custom user info.
- Refactored Bluetooth communication programming with the hardware device.
- Migrated the Xamarin.Forms-based project to .NET MAUI.
- Implemented the over-the-air Device Firmware Upgrade feature, enabling a firmware file to be transmitted over Bluetooth to the balance scale to self-upgrade its firmware. The Zibrio BalanceCoach app is available at the App Store.
Technologies: Xamarin, Cross-platform, Angular, Cloud, AWS IAM, HIPAA Compliance, Medical Software, .NET MAUI, Teamwork, SQL
Graduate Research Assistant
2019 - 2022
Concordia University
- Conducted state-of-the-art research on static source code analysis.
- Researched code refactoring, re-engineering, and maintenance.
- Developed a structured refactoring-based Diff viewer for JavaScript. This produces performed refactorings between two source codes.
Technologies: TypeScript, JavaScript, Java, Database Optimization
Full-stack Xamarin Developer
2019 - 2020
AudioLox Inc.
- Developed a multimillion-dollar MVP in Xamarin.Forms similar to Amazon Prime.
- Architected the whole mobile application using MvvmCross.
- Handled localization, RTL, stunning UI, and custom Skia animations and controls.
Technologies: Xamarin, C#, InVision, Sketch, Android, iOS, Mobile App Development, Media Players, Agile, Jira, Teamwork, NoSQL, MongoDB
Senior Software Engineer
2017 - 2019
Enosis Solutions
- Created an internationalized cross-platform native application in Xamarin.Forms available in Android, iOS, and Windows platforms. Extensively worked with PDFTron SDK to accommodate a full-blown PDF editor inside the app.
- Briefly worked on a Xamarin.Forms-based mobile app which is used for pickup dry cleaning. Made a beautiful circular menu.
- Built from scratch an automatic fuel pump payment mobile application in Xamarin.Forms. Used MvvmCross to make the code highly maintainable. Users can pay for fuel at a gas station via this app.
- Developed a POS system to be used at a gas station, which involves complex socket programming with security for card payment.
- Implemented mobile push notifications using OneSignal.
- Integrated a real-time fuel server with a custom TCP protocol with a POS system to enable payments via credit/reward cards for gas stations across Canada. The unique feature is that the app supports multiple languages simultaneously.
Technologies: ETL, XML Parsing, Cross-platform, Relational Databases, C#, Mobile Applications, Mobile App Development, Transact-SQL (T-SQL), .NET, SQL, Windows Presentation Foundation (WPF), Xamarin, Xamarin.Forms, Microsoft SQL Server, Teamwork, Database Optimization
Software Engineer
2015 - 2017
Enosis Solutions
- Developed 20+ ETL tools in C# and MS SQL Server for a large financial company.
- Wrote SQL queries in the most optimal format for generating quarterly and monthly financial statistics calculations using millions, even billions of rows of data.
- Parsed and loaded very large (20GB+) CSV, Excel, and XML files into a database, applying complex business logic in T-SQL.
- Wrote a custom CSV parser in raw C# to parse large CSV files with an odd number of delimiters inside multiple text qualifiers.
- Improved the existing investment performance calculation query, which resulted in faster execution for all ETL projects. Some even achieved 80% faster performance.
- Improved existing queries to detect non-continuous months in SQL, which increased performance by up to 30%.
- Handled small projects in Laravel, ASP.NET MVC with Ajax, and jQuery.
- Documented code regularly and maintained version control using Git, Sourcetree, and GitLab.
- Followed agile development and proper SDLC strictly.
Technologies: Transact-SQL (T-SQL), SQL, C#, Git, GitLab, Agile, Software Development Lifecycle (SDLC), SourceTree, Microsoft SQL Server, Teamwork, Database Optimization
Project History
Ufa Mobile
https://play.google.com/store/apps/details?id=com.ufa.ufa_mobile&hl=en_CAA mobile application for one of the largest oil and gas companies in Canada. The app features pay in the app, gas pump locations on the map, etc.
I have refactored the code to use the proper enterprise pattern, reduced complexity by separating view and view model, created a custom map control with selectable icons, improved location search speed by 1000x, and essentially acted as a development lead.
I have refactored the code to use the proper enterprise pattern, reduced complexity by separating view and view model, created a custom map control with selectable icons, improved location search speed by 1000x, and essentially acted as a development lead.
Custom In-house AI Project (Open Web UI)
Customization of the open web UI for specific company data searches, such as shipping status.
This custom version allowed the client to use different available models, such as DeepSeek or GPT-4, to run queries on company-specific data.
This custom version allowed the client to use different available models, such as DeepSeek or GPT-4, to run queries on company-specific data.
Zibrio
https://apps.apple.com/us/app/zibrio-balancecoach/id1452909451This CROSS Platform Xamarin Forms / .NET MAUI application needed the introduction of HIPAA compliance. Also, it supports over-the-air Device Firmware Upgrade (DFU) to its proprietary Balance Scale.
There is also an Angular-based dashboard and cloud provider where all the medical data are stored safely.
There is also an Angular-based dashboard and cloud provider where all the medical data are stored safely.
Music Player
https://drive.google.com/drive/folders/151axuSH8TElRcKr_2P6S7OtDi_Z3lS_l?usp=sharingA Xamarin.Forms-based application. Most of the front end was done by me. My contribution in the back end was limited to this four-member project.
The media player was similar to the amazon music app however was different in many aspects. Due to the impact of COVID-19, the project was ultimately scrapped off just before publishing.
Due to the nature of the app, I had to create custom plugins from scratch most of the time. This includes a custom navbar, custom iOS wheel slider on Android. Unique curved slider and more.
The media player was similar to the amazon music app however was different in many aspects. Due to the impact of COVID-19, the project was ultimately scrapped off just before publishing.
Due to the nature of the app, I had to create custom plugins from scratch most of the time. This includes a custom navbar, custom iOS wheel slider on Android. Unique curved slider and more.
Mobile Application | Boardroom Portal (Aprio)
This large Xamarin.Forms app runs on Windows, iOS, and Android platforms; it took eight months to build this app.
Features:
• Review and edit all board information in real time, while on the go.
• Make annotations for yourself, or for circulation to other members.
• Participate in discussions and polls/surveys.
• Easily view agendas while switching between meeting materials.
• View and edit schedules and calendars.
• Review meeting information and contacts.
• Work offline and maintain security.
• A single sign-on, you can use the same ID/password on both web and mobile apps to access information for all the organizations you’re involved in that use.
• A full-blown in-app PDF editor using PDF Tron SDK.
• MvvmCross was used to architect a highly maintainable design.
Features:
• Review and edit all board information in real time, while on the go.
• Make annotations for yourself, or for circulation to other members.
• Participate in discussions and polls/surveys.
• Easily view agendas while switching between meeting materials.
• View and edit schedules and calendars.
• Review meeting information and contacts.
• Work offline and maintain security.
• A single sign-on, you can use the same ID/password on both web and mobile apps to access information for all the organizations you’re involved in that use.
• A full-blown in-app PDF editor using PDF Tron SDK.
• MvvmCross was used to architect a highly maintainable design.
Education
2019 - 2023
Master of Science (MSc) Degree in Research in Software Engineering
Concordia University - Montreal, Canada
2011 - 2016
Bachelor of Science (BSc) Degree in Computer Science and Engineering
Ahsanullah University of Science and Technology - Dhaka, Bangladesh
Skills
Libraries/APIs
Xamarin.Android, Xamarin.iOS, React, Node.js
Tools
Git, GitLab, Microsoft Visual Studio, Visual Studio, Babel, AWS IAM, SourceTree, InVision, Sketch, Jira
Languages
SQL, Java, C#, Transact-SQL (T-SQL), XAML, JavaScript, TypeScript, CSS, Python
Frameworks
.NET MAUI, .NET, Windows Presentation Foundation (WPF), .NET Core, Angular, Media Players, .NET 8, .NET 7, .NET 9
Paradigms
Refactoring, App Development, Cross-platform, ETL, HIPAA Compliance, Agile, Azure DevOps
Platforms
Xamarin, Android, MvvmCross, Windows, Universal Windows Platform (UWP), Arduino, iOS
Storage
Relational Databases, XML Parsing, Microsoft SQL Server, MongoDB, NoSQL
Other
Xamarin.Forms, Teamwork, Database Optimization, Mobile App Development, Mobile Applications, Query Optimization, Network Programming, Web Development, Big Data, Re-engineering, Project Development, Data Structures, Algorithms, Mobile Apps, Cloud, Medical Software, Software Development Lifecycle (SDLC), javscript
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