Chris Liang
Verified Expert in Engineering
Software Developer
Vladivostok, Primorsky Krai, Russia
Toptal member since October 1, 2016
Chris loves creating web apps and iOS/Android apps. Over the past decade, he's developed more than 100 apps—providing a comprehensive UI/UX in geolocation service, real-time messaging, and other social features. He specializes in developing desktop and mobile apps related to real estate and food industries. Chris is an open-minded and personable developer who loves working with other developers in a team environment.
Portfolio
Experience
Availability
Preferred Environment
Visual Studio Code (VS Code), Android Studio, Xcode
The most amazing...
...thing I've built was a fitness coach management system in React (Apollo GraphQL) along with a React Native mobile app.
Work Experience
Senior Full-stack Developer
Everfit, Inc. (via Toptal)
- Built a dashboard to manage coaches (CRUD operation) with React (Apollo GraphQL) and iOS & Android mobile apps in React Native that are used by clients.
- Wrote customized webhooks for Twilio messaging between clients and coaches.
- Developed cron jobs to send notifications to coaches based on the SMSes received from the clients.
- Built a survey system for both web app and mobile app.
- Wrote migrations and seeding with Knex.
- Used the Serverless framework.
Senior Front-end Developer
Enroute 911
- Improved code quality by converting old JavaScript code to ES7 and via modularization.
- Reduced initial loading time by 300% by finding and fixing the logical errors in the code.
- Integrated Google Maps, MapBox, and several other map SDKs.
- Introduced Redux-saga to keep calling the RESTful APIs in the background.
Senior Mobile Developer
NZXT
- Developed a mobile app to get and update the PC status while playing games.
- Utilized BLE technology to get and connect with devices near a mobile phone.
- Called RESTful APIs for devices far away and used socket connection for devices near mobile phone to get the realtime data of the PC.
- Used GCD multithreading to call several APIs at once.
- Implemented Redux-saga to keep calling RESTful APIs in the background.
Senior Full-stack Developer
Flexible Fitness, LLC
- Updated non-structured code to MVC architecture.
- Integrated Apple HealthKit and Google Fit for retrieving user health information such as the number of steps and weight.
- Integrated Apple Pay and Google Pay for in-app purchase function.
- Integrated OneSignal for push notification.
- Developed the front end in React.js(Redux Saga) and the back end in Node.js (ExpressJS).
- Implemented Sketch design to pure HTML/CSS.
- Used Bluetooth Beacon to connect with fitness devices.
iOS Developer
MeeCard
- Implemented BaaS using Parse.
- Developed an offline mode using local storage.
- Helped to develop the business requirements.
- Developed a push notification using APNs.
iOS Developer
Textgreets
- Developed real-time messaging using QuickBlox.
- Implemented geofencing using Google Maps SDK and Core Location.
- Integrated an in-app payment using Stripe, ApplePay, and PayPal.
- Created UI animations using Core Animation.
- Developed an offline mode using CoreData and Realm.
- Made push notification using OneSignal.
- Developed unit testing and UI testing.
Senior iOS Developer
TextUs Biz
- Provided the business logic needed for point of sales.
- Developed an offline mode using Core Data.
- Created a payment integration using Braintree.
- Enabled a credit card validation feature using Card.io.
- Implemented Apple Pay.
- Used WatchKit and OpenGL.
iOS Developer
RapidSOS
- Built a location-based service using Core Location and Google Maps SDK.
- Created a push notification-based messaging service.
- Developed VoIP call using PJSIP library.
- Created UI and unit testing using XCTest.
- Developed an offline mode using Core Data.
iOS Developer
AppleSolutions DK
- Implemented a Shopify Client SDK and a Google Maps SDK.
- Added Apple WatchKit.
- Created a beacon using Estimote SDK.
- Added a payment integration using Apple Pay.
- Implemented a 3D touch feature.
iOS Developer
Beero
- Created rich animations using UIkit and Core Animation.
- Developed an offline mode.
- Enabled geofencing using Core Location and Google Maps SDK.
- Implemented a payment integration using PayPal.
Experience
TXG Mock Data Manager
To simulate the back-end functionality, the manager class loads PLIST files from an app bundle and utilizes them. It should be noted that this manager class is intended to be replaced by actual managers that communicate with the back end once it becomes available.
Beero iOS App
• Enabled geofencing using Core Location and Google Maps SDK.
• Implemented a payment integration using PayPal.
AppleSolutions
• Added Apple WatchKit.
• Created a beacon using Estimote SDK.
• Added a payment integration using Apple Pay.
• Implemented a 3D touch feature.
RapidSOS iOS and Android
• Created a push notification-based messaging service.
• Developed VoIP call using PJSIP library.
• Created UI and unit testing using XCTest.
• Developed an offline mode using Core Data.
TextUs Biz
• Developed an offline mode using Core Data.
• Created a payment integration using Braintree.
• Enabled a credit card validation feature using Card.io.
• Implemented Apple Pay.
• Used WatchKit and OpenGL.
Textgreets
• Implemented geofencing using Google Maps SDK and Core Location.
• Integrated an in-app payment using Stripe, ApplePay, and PayPal.
• Created UI animations using Core Animation.
• Developed an offline mode using CoreData and Realm.
• Implemented push notification using OneSignal.
• Developed unit testing and UI testing.
MeeCard
• Developed an offline mode using local storage.
• Helped to develop the business requirements.
• Developed push notifications using APNs.
Flexible Fitness React Native App
• Integrated HealthKit and GoogleFit for getting user details such as number of steps, weight, blood pressure, etc.
• Integrated Apple Pay and Google Pay for in app purchase feature
• Pixel perfect implementation of the new UI given by the client
• Used React.js(Redux-saga) for front end, Pure Javacript(ES5), and Node.js(ExpressJS) for backend
• Implemented Sketch design to pure HTML/CSS
KudosFit (via Toptal)
https://www.kudos.fit/Role: Senior Full-stack Developer
I built both desktop web app and mobile app in React (Apollo GraphQL) and React Native.
This project used Apollo GraphQL with a serverless framework for the desktop app. It was already on air and I needed to write a lot of migration scripts and seeding every time, I wrote a new function or add a new feature based on Knex.
I also built a dashboard to manage the coaches' apps (CRUD operation) and clients' iOS & Android mobile apps. I also wrote customized webhooks for Twilio messaging between clients and coaches and cron jobs to send notifications to coaches based on the SMSs received from the clients.
I was able to fix several bugs and add more than five new features of the app in less than two months.
Education
Master's Degree in Computer Engineering
Far Eastern Federal University - Vladivostok, Russia
Bachelor's Degree in Computer Engineering
Far Eastern Federal University - Vladivostok, Russia
Skills
Libraries/APIs
CocoaPods, Node.js, React.js, Facebook API, Parse SDK, Plaid API, Instagram API, Google Places API, Google Maps Development, Google Geocoding API, Yelp API, API, Mapbox iOS SDK, API, React.js, Vue.js, Twilio Development, Redux-Saga, Google Maps Development
Tools
Xcode, Android, Jira, Trello Development, Asana, Basecamp, OneSignal, React Apollo, Knex.js, MongoLab, Git
Languages
PHP, JavaScript, Swift, Objective-C, GraphQL, HTML, CSS, SCSS, TypeScript, C++, C, Java
Frameworks
Core Bluetooth, Cocoa, React Native, Angular, Express.js, Bootstrap, RealmSwift, MapKit, Serverless Framework, Laravel, Ruby on Rails, .NET
Paradigms
Model View ViewModel (MVVM), MVC Design, Agile Development, Agile Development, Model View Controller (MVC), Agile Development, Continuous Integration (CI), Scrum Master Consulting
Platforms
MacOS, iOS, Amazon EC2, Firebase, Visual Studio Development, iOS 12, Twilio Development, Oracle Development, Linux, WordPress Development, Android, Bluetooth Low Energy (LE), Mapbox
Storage
MS SQL, MySQL, Amazon S3, Elasticsearch, MongoDB, Realm, MySQLdb, SQLite
Other
Web Development, iPhone, iPad Development, Google Login, Stripe Payments, Geolocation, Data Mining, Apollo, iBeacon, Serverless, Bluetooth Beacons, Economic Development
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