Presentation at Tokopedia's event Behind Great Product : Build Your Code For the Future. Frandy and Herwidodo was presenting it. It was great experience both of them and they nail it.

1. Our Battle Against Technical Debt
Behind Great Product #3: Build Your Code for the Future
Frandy & Herwidodo, February, 24th 2017

2. Who are we?
• Frandy Jaya
• Binusian
• Join blibli in 2012
• Java & JavaScript
Developer
• Herwidodo
• Budi Luhur, Computer
Science
• Join blibli in 2015
• Front End Developer
– Focus on Performance
and technology

3. Agenda
• What is Technical Debt and why it is sometime
sensible to take it
• Our journey to tackle technical debt and
modernize our technology stack
• Peek into our future Front End technology

4. Blibli.com UI pre launch 2010

5. Blibli.com UI Circa 2012

6. Build Your Code for the Future
Technical Debt

7. Technical Debt
Technical Debt is a wonderful metaphor developed by
Ward Cunningham to help us think about this problem.
In this metaphor, doing things the quick and dirty way
sets us up with a technical debt, which is similar to a
financial debt.
Like a financial debt, the technical debt incurs interest
payments, which come in the form of the extra effort
that we have to do in future development because of
the quick and dirty design choice.
https://martinfowler.com/bliki/TechnicalDebt.html

8. Taking Technical Debt is Sensible
• Time to market trump good design when you
have unproven business
• Until it is hold you back, crippling your
productivity

9. Taking Technical Debt is Sensible
• Paying technical debt is hard, it needs support
from very top level
• Rewrite / Refactor based on proven
technology

10. Architectural Debt
Blibli.com SOA architecture circa 2013
Store Front
Back officeMerchant
ESB

11. Blibli.com UI Circa 2013
• Technology
– Dojo
– JSP
– JQuery
– Websphere Commerce Server
• Technical Debt
– Huge javascript file
– Slow backend
• Temporary remedies
– YSlow to evaluate
performance
– YUI Compressor
– Implement SOLR to help
backend performance issue

12. Blibli.com UI rewrite 2014

13. Technology
• AngularJS 1.2
• Responsive Design
• Solr 4
• Java 7, Spring and Tomcat
• Redis
• Google Pagespeed and Varnish

14. Combination of Server Side Rendering and SPA
• Checkout page is
SPA
• Product Detail page
is half SPA
• Catalog, search and
others are server
side rendering for
SEO puprpose

15. Content Problem
• Problem
– Content is scattered in Code
– No database to hold content data
– Multichannel UI is not possible
• Solution
– In House CMS system
– Save content in database
– Layout in database

16. Improved Architecture
Store Front
Engine
Back officeMerchant
ESB
Store Front
UI
SOLR
CMS
Internet

17. Responsive vs Adaptive
• Our responsive problem
– Desktop and mobile web UI share almost nothing,
all element are different
– Mobile web was really slow
• Responsive done right
– Start with mobile web design
– Make it responsive to desktop web
– Success example
• salestockindonesia.com

18. Mobile Web UI revamp to adaptive 2015
• One controller 2 completely sparate UI
• CMS support 2 layout : Desktop and Mobile
Web
• SASS and Grunt introduction on mobile web
UI
• SPA page still using responsive
• Mobile Web performance increase
dramatically

19. Break Monolithic to Microservices 2015
Store Front
UI
SOLR
CMS
Internet
20+ Microservices
to handle transactions
Travel UI
Digital
Product UI
10+ Microservices
to handle travel
10+ Microservices
to handle Digital Product

20. Front End Performance 2016
• Server side load < 1s
• Front end average load time ~ 12s
• What was the problem
– Blocked javascript execution
– DOM size ~ 700kb
– Page size ~ 3MB
– Single big CSS file block rendering
• Solution
– Differ javascript
– Decrease DOM size using ajax and lazy load
– Lazy load all image, start download when image in viewpoint
– Break CSS, inline CSS for layout and rendering
– Put third party JS at the and of DOM
• Result : frond end average load time ~4s - 6s

21. Front End Performance Result

22. Code Quality : Block Element Modifire (BEM)
• Maintainable
• Easy Tracking
• Modular
• Flexible
• Support partial load
• Fit with component based modern framework
ex : React, Vue, Polymer.

23. Brand new Travel UI is using BEM and SPA

24. Code Quality : Design System and Blistrap

25. Front-End Tooling and Development Cycle
• It is crazy time where front end developer
need compiler and build tools !!
– SASS
– Grunt : Concate & minify CSS + JS
• Existing UI application is basically Java Project
– Use Maven to build
– Use tomcat to run application
– Takes ~ 10 minutes from fresh build to application
ready

26. A Peek to Our Front End Technology in Future
• Separate backend and front end completely
– Single Page Application
– Backend as API
• Front End developer friendly tools
– VueJS
– SASS
– Webpack
– NodeJS to simulate route and response of Backend API
• Automated testing and quality gate
– VueJS unit testing
– CodeceptJS for acceptance test
• Reactive backend using Spring and RxJava to connect to
many microservices using nonblocking IO

27. We Are Hiring!!
THANK YOU