Curse or Cure

Rafał Warzycha


  • fullstack JS dev,
  • speaker,
  • podcast co-host,
  • conference maniac

Rafał Warzycha


Turbo Pascal, C#, TypeScript

Thank you!

Rising popularity

Overall magnitude

JavaScript in "real world"

Superset in theory

Superset in practice

TypeScript as a cure ...

TypeScript vs JavaScript

JS problems

  • class vs prototypical inheritance
  • object - oriented vs functional programming
  • conversion - casting vs coercion
  • variables  - block scope vs function scope
  • functions as variable - "first category citizen"

Main features

  • added compilation - types checks, ...
  • some of ES-next features - async/await
  • classes and interfaces,
  • editors autocomplete - really missed that,
  • strict rules via tslint - even on convention or editor level


Lessons learned


  • API is clear and readable
  • compilation time is ok,
  • features variety is stunning,
  • tslint is really powerful and useful,


  • JS is the vast ecosystem - not everybody is considering TS,
  • test, debug, build and package management is still nightmare - against all community effort,
  • code autocomplete comes with the price

TS is NOT a golden hammer

  • logical mistakes,
  • async runtime error,
  • you need to still understand JS, sorry :(
  • additional complexity
  • expensive to debug and automate,
  • 3rd party libs


Your responsibility

Thank you



Additional materials

  • http://slides.com/ducin/javascript-plus-java-equals-typescript
  • https://just4fun.io/odcinek-01-typescript/