Khaleel Shaheen, Developer in Gaza, Palestine
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Khaleel Shaheen

Verified Expert  in Engineering

Mobile Apps Developer

Gaza, Palestine

Toptal member since October 20, 2022

Bio

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

Infinum
Flutter, Dart, Agile Software Development, Mobile App Development, Bitrise...
alt.bank
Agile Software Development, Flutter, Dart, Cross-platform...
Islamic University of Gaza
Java, Digital Logic

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

Part-time

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

2021 - PRESENT
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.
Technologies: Flutter, Dart, Agile Software Development, Mobile App Development, Bitrise, Firebase, Clean Code, Mixpanel, Cross-platform, Mobile Development, REST, CI/CD Pipelines, Mobile, Agile, Test-driven Development (TDD), Cloud Firestore

Flutter Engineer

2018 - 2021
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.
Technologies: Agile Software Development, Flutter, Dart, Cross-platform, Mobile App Development, Android, Mobile Development, REST, Mobile, Agile

Teacher Assistant

2017 - 2018
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.
Technologies: Java, Digital Logic

Experience

Supanow: Mobile Dashboard for Supabase

https://supanow.app
Supanow is a powerful mobile app designed to help developers monitor and manage their Supabase projects on the go. It provides real-time insights into server performance, user activity, and database metrics through interactive charts and a spreadsheet-style table viewer. The app also features a storage file explorer, enabling users to browse buckets, preview images, videos, and audio files, and efficiently search and sort files.

I 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/
In my role on the Colour Varia project, I focused on implementing the app's design and enhancing its camera functionalities. I ensured that the user interface was both visually appealing and intuitive, aligning with the app's goal of providing personalized color analysis. By integrating advanced camera features, I enabled users to capture images and accurately extract colors, facilitating the generation of tailored color palettes based on their skin tone, hair, and eye color. This functionality allows users to discover complementary colors that enhance their personal style.

Vagabond Golf

https://vagabondgolf.com
Vagabond Golf is a Flutter-based mobile app for connecting golf players. The app allows regular people to reach out and play with golf players who can host them in their home clubs.

I'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/
I led a team of three developers in creating a pre-launch version of the Mara Wallet crypto mobile app. Mara Wallet is a platform for Africans to learn through and leverage blockchain technology to build digital wealth.

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/
I was part of the team that built the mobile application for the Shwra platform. Shwra is a digital platform that provides legal advice and services remotely in the Kingdom of Saudi Arabia by connecting clients seeking legal advice with a selection of accredited professional lawyers in an interactive, easy, secure, and professional manner.

Education

2012 - 2017

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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