
Khaleel Shaheen
Verified Expert in Engineering
Mobile Apps Developer
Gaza, Palestine
Toptal member since October 20, 2022
Khaleel is a professional cross-platform mobile engineer with over five years of experience building attractive and scalable Flutter applications. He has built apps for fintech, health, sports, and crypto startups and enterprises. Khaleel gets inspired by seeing his creations help users around the world.
Portfolio
Experience
- Flutter - 5 years
- Dart - 5 years
- Mobile Apps - 5 years
- Firebase - 5 years
- RevenueCat - 2 years
- Stripe - 2 years
- Bitrise - 2 years
- Supabase - 1 year
Availability
Preferred Environment
MacOS, IntelliJ IDEA, Flutter, Slack
The most amazing...
...software I've built is a crypto wallet mobile app that millions of people in Africa use to learn about, invest in, and trade crypto.
Work Experience
Flutter Engineer
Infinum
- Developed and maintained a pre-launch mobile app used as a marketing tool to collect the user base before the real app launch. The app used user referrals and a rewards system, converting millions of users in just four months.
- Built and maintained a high-quality and scalable crypto wallet mobile application.
- Created many internal tools used by developers to ease Flutter development workflows, like localizing applications.
Flutter Engineer
alt.bank
- Built the initial version of a wallet mobile application that allowed users to cash in and out, send and receive money from fellow users, pay bills, top up their phones, and perform many more online financial services.
- Redesigned and developed the onboarding flow, significantly increasing user retention.
- Implemented one-click deployment and distribution scripts, allowing easier frequent releases.
Teacher Assistant
Islamic University of Gaza
- Delivered weekly discussion lectures in Java programming classes and prepared and led laboratory classes within the digital logic design course.
- Guided students and motivated them to pursue their academic goals through monthly one-on-one sessions.
- Assisted professors in creating educational material for laboratory classes. The courses I worked for included introduction to computing, introduction to programming, and digital logic design.
Experience
Supanow: Mobile Dashboard for Supabase
https://supanow.appI led the entire development of Supanow, architecting the app with Flutter for a seamless cross-platform experience. I implemented secure authentication, optimized database queries for performance, and designed an intuitive UI for easy data navigation. Additionally, I integrated interactive charts and advanced filtering to enhance usability. My expertise in Flutter, Supabase, and mobile UX ensured a smooth, performant, and scalable app experience.
ColourVaria: Personal Colors Discovering App
https://www.colourvaria.com/Vagabond Golf
https://vagabondgolf.comI've built both sides of the app using Flutter for the mobile side and Appwrite BaaS open-source software for the back end. I've followed industry best practices for creating amazing and easy-to-use onboarding, profile creation, user engagement, and Stripe payment processes.
Mara Wallet
https://mara.xyz/My role involved planning and setting up the initial software architecture, developing and rolling out new features weekly, mentoring other developers, and reviewing their code to maintain a high-quality codebase.
Shwra for Legal Consultation
https://www.shwra.sa/Education
Bachelor's Degree in Computer Engineering
Islamic University of Gaza - Gaza, Palestine
Skills
Libraries/APIs
REST APIs, Stripe, Camera API
Tools
Git, GitHub, Codemagic, IntelliJ IDEA, Slack
Languages
Dart, Java, GraphQL, TypeScript
Frameworks
Flutter, Riverpod, JSON Web Tokens (JWT)
Paradigms
Agile Software Development, Clean Code, Mobile Development, REST, Agile, Clean Architecture, Continuous Integration (CI), Continuous Delivery (CD), Test-driven Development (TDD), Cross-platform
Platforms
Android, iOS, Mobile, RevenueCat, MacOS, Firebase, Bitrise, Mixpanel, FlutterFlow
Storage
Cloud Firestore, SQLite
Other
Mobile App Development, Cross-platform App Development, Mobile Apps, API Integration, CI/CD Pipelines, Supabase, APIs, Application State Management, Documentation, Back-end as a Service (BaaS), Digital Logic, Deployment, App Store Connect, Google Play Console
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