Zhenju Kou, Developer in Tokyo, Japan
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Zhenju Kou

Verified Expert  in Engineering

Software Engineer and Developer

Tokyo, Japan
Toptal Member Since
December 14, 2023

Zhenju is a senior back-end engineer with 8+ years of experience in multiple threading processes and REST API design. His experience spans eCommerce, social, and industrial sectors, showcasing high enthusiasm, integrity, and ingenuity. Zhenju excels in fast-paced, competitive environments, demonstrating a result-oriented mindset, self-motivation, and resourcefulness. His comprehensive skill set makes him a valuable asset in any technological endeavor.


Java 8, Scala, Spark, GitLab CI/CD, Jenkins, Amazon Elastic MapReduce (EMR)
Java 8, Spring, Spring Boot, Ethernet, Web3, Go, Solidity, Redis Cache, NGINX...
Tata Consultancy Services
Java 8, React, LokiJS, GraphQL, ETL




Preferred Environment

IntelliJ IDEA, Slack, Web, Spring, Spring Boot, Spring Cloud, Apache Kafka, Apache RocketMQ

The most amazing...

...thing I've built is a tool for processing and verifying big data, which has eight layers, each comprising millions of partitions with hundreds of objects.

Work Experience


2022 - 2023
  • Constructed a development and testing ecosystem leveraging AWS, focusing on creating verified tools to ensure the suitability of all data for a multiple-user system (MUS).
  • Conducted product testing using the Amazon Elastic MapReduce (EMR), Amazon EC2, and the OLP platform.
  • Utilized Spark to process data and stored the processed data in the MUS service.
  • Built an automated verification pipeline using GitLab's CI/CD.
Technologies: Java 8, Scala, Spark, GitLab CI/CD, Jenkins, Amazon Elastic MapReduce (EMR)


2021 - 2022
  • Achieved the goal of inviting users through various applications, demonstrating effective multi-channel user outreach.
  • Reconstructed Atoshi online mall into microservices, optimizing its architecture for enhanced scalability and efficiency.
  • Developed and deployed game services. Identified and resolved bugs to ensure a smooth and error-free gaming experience.
Technologies: Java 8, Spring, Spring Boot, Ethernet, Web3, Go, Solidity, Redis Cache, NGINX, MySQL


2020 - 2021
Tata Consultancy Services
  • Completed the delivery by addressing the ticket demands and updating the task listing on Jira.
  • Conducted testing on the stock information processing module and troubleshot to address any identified issues.
  • Developed the module for the TV series Bonding and successfully executed it in the production environment.
Technologies: Java 8, React, LokiJS, GraphQL, ETL

Junior Development Engineer

2016 - 2020
Hunk Times
  • Scheduled the acquisition of room type information from the supplier, handling a dataset of approximately seven million records.
  • Headed a team in designing and delivering hotel order modules, demonstrating effective leadership in project execution.
  • Led a team in delivering a Notice module that sends results to the client via text messages.
  • Migrated an eshop program, transforming the legacy system into a microservice architecture for enhanced scalability and efficiency.
Technologies: Java 8, Elasticsearch, Vue, Apache Dubbo, Apache ZooKeeper, MyBatis, Apollo

A JSON Compare Tool

A standard tool for JSON object verification known for its exceptional speed, robustness, and safety. It is seamlessly integrated into production environments. It features convenient mechanisms for skipping verification processes and adeptly handles String and JSONObject items.
2011 - 2016

Bachelor's Degree in Software Engineering

Beijing Union University - Beijing, China


React, API Development, GSON, Vue, MyBatis, jQuery


RabbitMQ, IntelliJ IDEA, Slack, GitLab CI/CD, Jenkins, Amazon Elastic MapReduce (EMR), NGINX, Apache ZooKeeper, Azure Key Vault


Java 8, Java, Scala, Go, Solidity, GraphQL, HTML, CSS, JavaScript


Spring, Spring Boot, Spark


JSON, Redis Cache, MySQL, LokiJS, Elasticsearch, MariaDB, PostgreSQL, MongoDB, Alibaba Cloud


Agile, Testing, ETL


Apache Kafka, Apache RocketMQ, Amazon Web Services (AWS), Web, Azure, Amazon EC2


Back-end, APIs, Spring Cloud, Full-stack, CI/CD Pipelines, Webex, English, Ethernet, Web3, Apache Dubbo, Apollo, Architecture

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