Apurbalal Singha, Developer in Tokyo, Japan
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Apurbalal Singha

Verified Expert  in Engineering

Front-end Developer

Location
Tokyo, Japan
Toptal Member Since
September 14, 2022

Apurbalal graduated from IIT Madras, India. Soon after graduating, he moved to Japan to work in Mercari as a software engineer. He has developed user-facing features for both web and mobile apps used by millions of users every day. Apurbalal has professional experience in developing web, Android, and iOS applications. He values writing clean, readable, testable, and scalable code and loves working on complex front-end projects.

Portfolio

Japan Job Space
React, Next.js, TypeScript, Firebase, Algolia, Firebase Cloud Functions...
Upexpat
React Native, Android, iOS, Algolia, Video Chat, Audio Chat, Messaging, Stripe
Mercari
React, Next.js, GraphQL, JavaScript, TypeScript 3, Unit Testing...

Experience

Availability

Part-time

Preferred Environment

Slack, CI/CD Pipelines, GitHub, Google Cloud Platform (GCP), MacOS, Chrome Extensions

The most amazing...

...things I've developed are user-facing features for the Mercari website, such as chat, offers, order status, and nationwide shipping, used by millions of users.

Work Experience

Senior Full-stack Developer

2023 - PRESENT
Japan Job Space
  • Developed a job listing website using Next.js and hosted it on Vercel.
  • Created features such as interview practice using ChatGPT.
  • Gained 30,000 monthly active visitors and 500+ newsletter subscribers after the launch.
Technologies: React, Next.js, TypeScript, Firebase, Algolia, Firebase Cloud Functions, Cloud Firestore, ChatGPT

Senior Full-stack Developer

2022 - PRESENT
Upexpat
  • Built Upexpat, a social media platform for foreigners visiting Japan to help with their everyday needs.
  • Developed app features like authentication, social media timeline, chat, video, and audio calls.
  • Integrated various 3rd-party services: Stripe for payment, LiveKit for video and audio calls, GetStream for social media timelines, and Algolia for search.
Technologies: React Native, Android, iOS, Algolia, Video Chat, Audio Chat, Messaging, Stripe

Web Developer

2019 - PRESENT
Mercari
  • Developed incentive service on the Mercari website, which is used to give coupons to users for promotions.
  • Created an offer to Liker and made an offer for sellers and buyers to increase sales.
  • Developed a return flow through which buyers were able to return their items.
  • Improved Mercari website build speed by five times and improved deployment.
  • Migrated the codebase from Flow to TypeScript language to meet industry standards.
  • Moved the chat service from a PHP codebase to a modern web tech stack codebase. Added more features such as offers and system admin messages.
  • Managed sprint planning, grooming, and retrospective meetings as a scrum master. Helped the team to achieve good team velocity and complete more tasks.
Technologies: React, Next.js, GraphQL, JavaScript, TypeScript 3, Unit Testing, CI/CD Pipelines, Google Cloud Platform (GCP), TypeScript, Apollo Server, Node.js, Android, Java, Kotlin, RxJava 2, iOS, Front-end, DevOps, Web Development, Agile, Full-stack, Leadership, CSS, HTML, Web & Mobile Applications, Git, Serverless Framework, Software, Architecture, APIs, Software Development, Chatbots

Software Engineer

2022 - 2023
Penta
  • Developed a web marketplace to buy NFT headphones by connecting with a crypto wallet.
  • Developed a React Native app that tracks songs played in the background in iOS and Android and gives awards to the user in the form of Penta Stones. Also wrote native modules to share background music information between native code and React.
  • Set up Google Cloud Platform and Sentry to track errors and the cause of errors our end users face.
Technologies: React Native, React, Next.js, Firebase, Google Cloud Platform (GCP), AWS Lambda, Software, Architecture, APIs, Software Development

Android Engineer

2018 - 2020
Mercari
  • Migrated chat service from React Native to the native codebase, which buyers and sellers use. Currently, it is used by millions of monthly active users.
  • Developed user tracking feature in the app to track user interactions.
  • Tracked and fixed bugs in the Android app and used Jira to report and track issues.
Technologies: Android, Kotlin, RxJava, RxKotlin, Dagger 2, Flux Architecture, Unit Testing, CI/CD Pipelines, Agile Delivery, GitHub, Code Review, Web & Mobile Applications, Software, Architecture, APIs, Software Development, Chatbots

Software Developer

PENTA is a "Music Adventure Game" in which the game progresses through music playback. You can discover the PENTA STONE by listening to music and growing your own headphones. At Penta, I developed their mobile and web apps.

Pawllet

https://www.producthunt.com/products/pawllet
Soon after graduating in India, I moved to Japan to work as a software developer. While in Japan, I noticed that websites or services did not provide good information about dietary-specific restaurants and their menu items.

Even if we search for vegan or vegetarian restaurants using the existing websites in the market, it's still very difficult to find detailed menu information. None of these websites lets us search restaurants by food name or description. Thus, the only option is to go through the restaurant's official website or call each restaurant directly. This is important because, in Japan, many menu items are said to be vegetarian, yet they often contain animal fat.

All these problems led me to the idea of Pawllet. This platform provides detailed menu information of dietary-specific restaurants, and users can search restaurants by food name, description, location, etc.

Lottus

https://www.producthunt.com/products/lottus-learn-share-and-grow
An Android and iOS mobile app that provides users with a platform to share their knowledge and help each other learn something new daily. The app has various use cases, including:

• Preparation questions, theories, or tips to help students prepare for the joint entrance examination
• Popular interview questions to help users learn and prepare for interviews
• Science facts, general knowledge, and more

Save Dodger | Android Game

Developed an Android game in Unity. This is a 2D action-paced game developed in Unity 2D. The sprites are created in Figma and animated in Unity Sprite Animation. The game got more than 10,000+ downloads on Play Store.

Frost Runner | Android Game

https://www.youtube.com/watch?v=U9AOvUw3J_s
Developed infinite 3D runner game in Unity. The character and environment are designed using Blender and Adobe Photoshop. The environment is randomly generated, creating a unique gaming experience. Developed this game in the India Hacks HackerEarth and received 13th position all over India.

Point Card Wallet

Developed an iOS app that lets users scan their point cards and save them in the app. The users can redeem the points just by showing the app without the hassle of carrying physical point cards.

MVC architecture: developed the app using the MVC architecture pattern.

Firebase: used Firebase for authentication and storing user and point card data.

Odyssey Game Development

https://youtu.be/2V8iebw_Reg
An infinite running android game where the player has to tap the phone screen to clear the obstacles. The player also need to collect coins on the go and they can buy characters, change weather and unlock new levels using the collected coins.

Created using Unity 3D, Photoshop, and Blender.

Developer

http://www.mercari.com
• Developed incentive service on the Mercari website, which is used to give coupons to users for promotions.
• Created an offer to Liker and made an offer for sellers and buyers to increase sales.
• Developed a return flow through which buyers could return their items.
• Improved Mercari website build speed by five times and improved deployment.
• Migrated the codebase from Flow to TypeScript language to meet industry standards.
• Moved the chat service from a PHP codebase to a modern web tech stack codebase. Added more features such as offers and system admin messages.
• Managed sprint planning, grooming, and retrospective meetings as a scrum master. Helped the team to achieve good team velocity and complete more tasks.

Software Engineer

• Developed a web marketplace to buy NFT headphones by connecting with a crypto wallet.
• Developed a React Native app that tracks songs played in the background in iOS and Android and gives users awards in the form of Penta Stones.
• Wrote native modules to share background music information between native code and React.
• Set up Google Cloud Platform and Sentry to track errors and their cause.

Android Engineer

http://www.mercari.com/
• Migrated chat service from React Native to the native codebase, currently used by millions of buyers and sellers monthly,
• Developed a user tracking feature in the app to track user interactions.
• Tracked and fixed bugs in the Android app and used Jira to report and track issues.

Libraries/APIs

React, Node.js, RxJava 2, RxKotlin, ReSwift, RxJava, Stripe

Tools

GitHub, Git, Slack, Photoshop CS5, Figma, Blender, Photoshop 7, ChatGPT

Frameworks

Next.js, React Native, Unity, Ant Design, Serverless Framework, Unity 3, Unity2D, Unity3D, Dagger 2

Languages

TypeScript, GraphQL, JavaScript, TypeScript 3, Java, Kotlin, CSS, HTML, Swift, C#

Storage

Databases, PostgreSQL, Elasticsearch, Redis Cache, Cloud Firestore

Paradigms

Agile, DevOps, Unit Testing

Platforms

Android, Kubernetes, iOS, Firebase, Algolia, Google Cloud Platform (GCP), MacOS, Blockchain, AWS Lambda

Other

Front-end, Web Development, Full-stack, Web & Mobile Applications, APIs, Software, Software Development, Apollo Server, Code Review, Game Development, API Integration, CSS3 Animation, Architecture, Chrome Extensions, Chatbots, CI/CD Pipelines, Progressive Web Applications (PWA), GetStream.io, Leadership, Google Play Store, Scanning, Mobile Apps, Flux Architecture, Agile Delivery, Mobile App Development, Web App Development, Artificial Intelligence (AI), Firebase Cloud Functions, Video Chat, Audio Chat, Messaging

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