Web Development with Kotlin

In this course, we’ll build a microservice using Kotlin programming language and Ktor framework, then deploy it to Heroku.

The microservice will be for a cat hostel. You’ll be able to add new cats and remove and list them.

Why cats?

Because as long as you know how to implement basic operations, you can build it any kind of service you may need: supermarket orders, auction items, taxis, you name it. So, why not cats?

Why Kotlin?

• Modern, productive, and highly pragmatic language
  • Type safe
  • Null-safe
  • Generics that make sense
  • Intuitive
  • Extensible
• Highly concurrent: Kotlin uses coroutines on top of best-in-class JIT provided by the JVM, which makes it one of the most efficient and concurrent languages nowadays
• Rich ecosystem be it PostgreSQL, Kafka, or RabbitMQ, the most solid libraries are written for the JVM. And Kotlin can make use of all of them

Why this course?

There are many good tutorials and books about Kotlin programming language nowadays. But most of them assume that you’re either an Android developer or at least familiar with Java programming language and its ecosystem.

This course makes no such assumptions. If you’re an experienced PHP, Python, Ruby, or NodeJS developer, with zero Java knowledge, this course was built with you in mind.

What you need to know:

Some kind of web technology, be it JavaScript, PHP, Ruby, or Python. I expect you to be familiar with terms like Request, Response, JSON, and HTTP headers at the very least.

Familiarity with Git. I’ll provide you with a link to the relevant branch on GitHub after most of the videos, and I’ll show you commands that I use, but I won’t dive deep into what they do.

Basic SQL and Docker knowledge is useful, but not mandatory.

What this course covers:

• Basics of Kotlin programming language
• Dependency management with Gradle
• Store web framework
• Testing with Kotlin
• Working with databases using Exposed DSL
• Running Kotlin inside Docker container and Docker Compose
• Deploying Kotlin to Heroku
• Exposing GraphQL API with Kotlin

What this course doesn’t cover:

• Coroutines
• Building UI in Kotlin
• CI tools
• Security

Each of them is a large topic by itself, and I wanted to keep this course as focused as possible, so you’ll be able to produce a working and well-tested application in an hour or two.