Damien Doumer Kake
Verified Expert in Engineering
Software Engineer and Developer
Damien is an experienced software engineer who focuses on offering real-world solutions for complex ideas and problems. He is well-versed in turning plans into impactful, robust, well-architected, and fault-tolerant software systems. Damien's technology skills include Flutter, .NET, ASP.NET Core, Xamarin, and .NET MAUI.
Portfolio
Experience
Availability
Preferred Environment
.NET, ASP.NET Core, Flutter, Xamarin, Back-end, Mobile, C#, API Development, OpenAI, Chatbots
The most amazing...
...app I've led the construction of is YouScribe, a Netflix-like platform offering books used by millions of users, primarily located in Africa.
Work Experience
Back-end and Mobile Software Engineer
YouScribe (The Netflix for Books)
- Acted as a mobile and back-end senior engineer for YouScribe, a company known as the Netflix for books. It has thousands of text and audiobooks, and users can stream, download, and consume the content on a subscription basis.
- Maintained the YouScribe app and reduced its crash rate by more than 90%. Increased the overall rating frequency by over 50% and optimized it for speed and reliability.
- Led a team while migrating YouScribe's legacy back-end infrastructure from ASP.NET to ASP.NET Core with microservices, clean architecture, OpenID Connect (OIDC), etc.
- Architected the new back-end platform, leveraging a microservices architecture, clean architecture, CQRS, OpenID Connect (OIDC), and ASP.NET Core.
- Led a team of two engineers in the 2nd migration of the YouScribe app to Flutter from Xamarin.Forms.
- Optimized the back end for speed and reliability, including correcting bugs and rewriting several components for optimization.
- Led the migration of YouScribe's mobile app from Xamarin Native to Xamarin.Forms.
- Upgraded the platform's authentication system and built a compatibility layer to link legacy clients with new microservices in a reliable way.
- Implemented native Kotlin/Java and Objective-C/Swift features using platform channels in Flutter.
- Maintained and evolved some of YouScribe's back-end services.
Full-stack Software Engineer
Kickle
- Worked as a full-stack software engineer for Kickle. This company builds meeting software such as collaborative whiteboards, video conferencing, etc, using ASP.NET Core and Angular with Electron for its desktop app.
- Implemented real-time communication with client apps, using SignalR in ASP.NET Core and Angular; this feature was required for real time collaboration on the whiteboard software. Users could draw in real-time and interact together.
- Added data caching with Redis. This was required to rapidly communicate between the microservices and save the real-time connection and data shared via SignalR.
- Intervened by creating microservices with ASP.NET Core and implementing domain-specific features in a team of three back-end engineers.
- Worked as a lead mobile developer on Kickle's mobile app, part of its meeting software pack.
- Leveraged TypeScript to add features to the Angular web app.
- Worked with Electron and OS-specific features (Windows and Linux), including process management, file access, installers, registry management, and services management.
Back-end and Mobile Software Developer
HKB Ventures
- Built a mobile back-end MVP for this client's startup. This MVP was an app for users to ship products, leveraging maps and real-time data.
- Developed a mobile app where users could monitor the location of other users to deliver parcels in real time.
- Created a back-end API with ASP.NET Core, offering authentication, CRUD operations, and real-time client communication.
Back-end and Mobile Engineer
Infinite Square
- Joined the team as a .NET back-end and mobile software engineer at Infinitesquare, a company that builds many SaaS products for many clients. They use Microsoft tech principally.
- Built back-end software with ASP.NET Core, considering use cases specific to each client (Infinite Square's clients).
- Worked with three developers to build cross-platform mobile applications with Xamarin.Forms.
- Developed a Microsoft Teams bot leveraging Microsoft Graph API. This bot acted as a support agent for the Infinitesquare team.
Software Engineer
Freelance Software Engineer
- Acted as a freelance independent developer and built software solutions for multiple clients, using .NET and C# as the primary technologies to make anything from desktop and mobile apps to bots.
- Developed desktop apps with Windows Presentation Foundation (WPF) for client-specific scenarios.
- Designed and built software to interact with specific user hardware, including the device's mouse and camera.
- Created bots using Microsoft Bot Framework and mobile apps using Xamarin.Forms and Flutter.
Experience
Personal Blog
https://doumer.me/Architected, Optimized, and Improved the Security of YouScribe's New Back End
The YouScribe App
https://play.google.com/store/apps/details?id=youscribe.mobileappMaktabati
https://doumer.me/portfolio/maktabati-android-ios-app-at-youscribe/Freechat
https://github.com/DamienDoumer/freechatEducation
Bachelor's Degree in Computer Engineering
University of Buea - Buea, Cameroon
Certifications
Microsoft Most Valuable Professional (MVP)
Microsoft
Google Africa Challenge Mobile Web Specialist Course
Udacity
Skills
Libraries/APIs
API Development, REST APIs, Entity Framework, MediatR, SignalR
Tools
Visual Studio, Git, ChatGPT, Dapper, RabbitMQ
Frameworks
ASP.NET Core, Flutter, .NET Core, .NET, ASP.NET, Entity Framework Core, Angular, Angular 7, Electron, Windows Presentation Foundation (WPF), .NET MAUI
Languages
C#, C#.NET, Dart, SQL, TypeScript 3, JavaScript, TypeScript
Paradigms
Mobile Development, Microservices, Cross-platform, App Development, Azure DevOps, Back-end Architecture, CQRS, Microservices Architecture, Clean Architecture, Test-driven Development (TDD)
Platforms
Xamarin, Android, iOS, Azure, Firebase, Microsoft, Microsoft Bot Framework, Mobile
Storage
MongoDB, PostgreSQL, Google Cloud, MySQL, Redis Cache
Other
Software Engineering, .NET 7, Back-end, Mobile Apps, API Design, Back-end Development, Full-stack, Minimum Viable Product (MVP), APIs, Mobile Back-end, Mobile Applications, Full-stack Development, Technical Writing, OpenAI, CI/CD Pipelines, Web3, Community, Computer Engineering, OpenID Connect (OIDC), Xamarin.Forms, Microsoft Graph API, Optimization, Cloud, Native Mobile Apps, Mobile App Development, .NET 8, Chatbots, Front-end, AI Chatbots, Web Development, RESTful Microservices, Artificial Intelligence (AI)
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