Line Developer Days 2016 talk review

Line Developer Days 2016, it is a line tech sharing big event, all sessions are for developer. I have to say, there are all infrastructure we can know how line did it, and include mechanism and technical problem that is line faced, and how line developers slove them.

Line corp already released slide here, you can download or share in public.

It is a two courts, there are notes what i organize.



Line bot is getting better, now you can easy to use, they already integrate with github and ITFFF and other services without code. Also they announce Line beacons and messaging API, Line bot can be a online service for your customers.


In the pass, Line faced the crash issues, I discover Line devote lots service or monitor and log system to prevent crash happen again.
Also they use Kafka, Hbase, Flink as base infrastructure, and connect by RPC, cowork with other micro service.

It is a big system, but separate to different components and micro services, that will be easy for maintain and development.


Line login already implement oauth2.0, now it open oauth2 basic stater in Java, you can easy to deploy to heroku and modify from starter code base. And you can make users use line login as facebook authentication flow, easy and fast.
In another word, they already release auto login flow, but not so many detail information, but I think the flow will be very similar with wechat.

Tech talk

【A-5】Security x LINE Platform

For line message the base encode methodology is end to end encryption(E2EE) via Line server, Line talk server will have a share key generated for part of decryption, so on Group chat are same flow, it just duplicate share keys for those whom in chat group.

Other, Except log service and monitor system, I believe that Line have a lots of QA, and they have to guarantee all services run well and make system health.
Well, Another way is from outside, that is Bug bounty plan, that is always a good way to figure out leake or bug in system from outside report.


For solving graph database issue, they have to search user's relation and chaining together in short time response. I think Gravty is Line solution to convert MySQL (or relation database) to have a graph like function. Redis and MySQL is base, and make it runs parallel research. From MySQL infrastructure combine with other micro service and mechanisms, that is a interesting sharing.

【A-7】LINE LIVEを支えるアーキテクチャ

Line live, it is a real time p2p streaming service, you can give LOVE to streamer and chat. From infrastructure chart, they saved all media data in media server and also make user can replay, also include chat information and interaction log in different servers. I have to say streaming is all ways with big burn rate, that is fun for client, but hard work for developers, it is a big challenge.

【B-7】A True Agile Team - Global LINE News

Scrum, that is always we do in agile team, but trust and self-management is always hard to implement in team even a cross team. Line Taiwan had a good example for how they build and fix thing in team, I think there are so many gaps they already transited, agile is a top-down issue, and manager have to always follow agile spirit, I think they already did it.

In the end


Line already open source some project from internal and continue to maintain and make them better. Line make an API friendly environment and platform for developers easy implement. I believe "positive peer pressure" that is good way to make people productivity and making more motivation, how to make developer keep passions and have agile spirit, it is a long term journey.

Line developer days 2016 is a one day event, most are focus developers. I think Line next is moving to cross IOT and behavior integration around line, they want to be your life cycle and trying change the world.

From technical sharing we can get infrastructure and domain knowhow, there are many detail i don't mention in slides, all slides are worth to read again, hope you enjoy it.


Web developer, focus on website fullstack, special JavaScript, and love sharing developing experience and communicate with developers.