Building Large Kubernetes Clusters

Introduction LINE supports its developers so that they can fully focus on development. This was the background of implementing Nucleo, LINE’s in-house Kubernetes-based service, taking care of infrastructure on behalf of developers. Nucleo currently services 800 apps with about 4,000 pods. The number of apps is growing by the minute. All the workloads are being managed …

LINE Android & iOS Engineer Workshop and Hackathon 2019

Hello everyone, I’m Aldo, an Android developer at LINE. In this article, I’m going to share my experience in attending LINE Developer Workshop and Hackathon 2019. The aim of the event was in “closing the distance” between LINERs; since for the most part, we usually only communicate through online platforms. Android and iOS developers from …


What is COSCUP COSCUP is one of the biggest open source conferences around Asia. It is an annual conference that has been held by the open source community since 2006 and acted as the major advocate of the free open-source software movement (FOSSM) in Taiwan. COSCUP is composed of talks, sponsor and community booths, and BoF (Birds of a …

UIT Global Workshop 2019

LINE offers various services in the global scene, ranging from its famous instant messaging, content delivery (e.g., news, music, and video), and financial services (e.g., LINE Pay and personal finance app). The UIT team at LINE is responsible for the web front-end technology of these services, working hard across different time zones from Korea, Japan, …

NAVER x LINE AI RUSH 2019 – My Experience of the Final Round

At the LINE DEVELOPER DAY 2018 conference held in Tokyo, LINE Corporation CTO Park Euivin announced “Next LINE” as LINE’s vision in the development of technology. In this vision, AI (Artificial Intelligence), blockchain, and fintech would play a pivotal role. “Connect” and “Mutually Beneficial Ecosystem” were touted as significant keywords that would lead the organization …

Verda at CloudNative/OpenStack Days 2019 (2/2)

This blog post is the second part that continues from Verda at CloudNative/OpenStack Days 2019 (1/2). In the previous post we took a look at the overall ecosystem of Verda. In this post I will explain our network side challenges and how we optimized and improved Verda to overcome those challenges.

LINE’s Verda Network designs:

Lets go through the 3 transitions of LINE data center networks.

  1. L2-based network backed with upstream solution using Linux bridge
  2. L3-only flat network: Developed by LINE OpenStack engineers
  3. L3 Base Overlay network: Developed by LINE engineers

Verda at CloudNative/OpenStack Days 2019 (1/2)

Ever wondered what LINE uses internally for infrastructure management? If yes, then you came to the right blog post.
Recently at CloudNative/OpenStack Days Tokyo, LINE presented on its OpenStack cloud project called Verda.

This article is going to be a series of two blog posts which provide a summary of the entire Verda ecosystem:

  1. Verda at CloudNative/OpenStack Days 2019 (1/2)
     → Bird’s eye view of Verda
  2. Verda at CloudNative/OpenStack Days 2019 (2/2)
     → LINE’s network design to meet private cloud user requirements

In this blog post, we’ll be looking through a bird’s eye view of LINE’s OpenStack project Verda and introduce you to the entire OpenStack ecosystem that LINE has. Without further ado, let’s begin!

LINE’s Web-based services and technology. Isn’t LINE an app developer?

Hello to all! I’m Seok Heo, a web service developer at LINE. I’d like to introduce you to LINE’s various web-based services and their architecture, technology stack, and development methodologies in this post. To simplify things, I’ve classified LINE’s web-based services into web services, hybrid web apps, messenger, and library/platform.

LINE Taiwan Security Meetup – BECKS #3

Information security has always been one of the key focuses of LINE. LINE has always strove to actively promote various security enhancement strategies over the years. As a part of our ongoing effort towards information security, LINE information security engineers hold a meetup known as BECKS (a portmanteau of beer and hacks) in Korea, Japan, …

The Repetitions Eliminator R Library “mmetrics”

Have you ever faced a situation where you need to compute the same metrics using similar or even the same computation formulas over and over again? How do you usually handle those repetitive tasks? As many engineers in our field of work know, dplyr is one of the most cool and efficient data wrangling grammars that provide us …