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Master Kotlin with Adaptive AI.

Master Kotlin across 28 topics - Foundations, OOP and Functional Patterns, and Coroutines and Advanced Kotlin - guided by Leyaa's adaptive intelligence.

3Parts

28Topics

248Patterns

60hEst. duration

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Kotlin Course

3 - part learning journey

Foundations

9 topics · 83 patterns

Beginner

OOP and Functional Patterns

9 topics · 81 patterns

Intermediate

Coroutines and Advanced Kotlin

10 topics · 84 patterns

Advanced

Begin Part 1: Foundations

✦ Course Structure

Your Kotlin Journey in 3 Parts

Each part builds on the last - a deliberate progression from beginner to advanced.

Beginner

Part 1: Foundations

Covers Kotlin Basics and JVM Runtime, Variables and Type System, Data Types and 6 more topics.

9Topics

83Patterns

View topics

Intermediate

Part 2: OOP and Functional Patterns

Covers Lambda Expressions and Higher-Order Functions, Collection Processing, Scope Functions and 6 more topics.

9Topics

81Patterns

View topics

Advanced

Part 3: Coroutines and Advanced Kotlin

Covers Generics, Coroutines Fundamentals, Coroutines Advanced and 7 more topics.

10Topics

84Patterns

View topics

Curriculum

Everything You'll Learn

Explore every topic and pattern in the course.

Kotlin

3 parts · 28 topics · 248 patterns

Part 1: Foundations9 topics · 83 patterns

Beginner

Kotlin Basics and JVM Runtime

8 patterns

What is Kotlin

Why Kotlin over Java

How Kotlin compiles to JVM bytecode

Kotlin REPL and script mode

Main function as entry point

Print and println output

Comments and documentation syntax

Project structure and build basics

Variables and Type System

8 patterns

Why immutability by default matters

Val for immutable references

Var for mutable references

Type inference by the compiler

Explicit type declaration

String templates and interpolation

Constant values with const val

Type checking with is operator

Data Types

10 patterns

Why Kotlin has no primitive types at source level

Int, Long, Float, Double number types

Boolean type and logical operators

Char type and Unicode behavior

String type and immutability

Type conversion is always explicit

Number literal formats (underscore, hex, binary)

Any type as universal base

Unit type as void equivalent

Nothing type for functions that never return

Null Safety

10 patterns

Why null safety is Kotlin's defining feature

Non-nullable types by default

Nullable types with ? suffix

Safe call operator (?.)

Elvis operator (?:) for default values

Not-null assertion (!!) and its danger

Safe casts with as?

Let function with safe calls

Null safety in collections

Platform types from Java interop

Operators and Expressions

9 patterns

Why operators are functions in Kotlin

Arithmetic operators

Comparison operators

Equality (== structural vs === referential)

Logical operators (&&, ||, !)

Range operator (..) and in operator

Elvis operator deep usage

Operator overloading concept

Operator precedence

Control Flow as Expressions

9 patterns

Why expressions over statements matters

If as an expression returning value

If-else expression assignment

When expression as powerful switch

When with multiple conditions

When without argument

When with ranges and types

When as expression returning value

Smart casts in when and if

Loops and Ranges

9 patterns

Why ranges simplify iteration

For loop with ranges

For loop with step and downTo

For loop over collections

For loop with index (withIndex)

While and do-while loops

Break and continue behavior

Labeled break and continue

Repeat function for simple repetition

Functions

10 patterns

Why functions are first-class in Kotlin

Function declaration syntax

Parameters with default values

Named arguments for clarity

Single-expression functions

Unit return type

Nothing return type for unreachable

Local functions (nested functions)

Infix functions for readable calls

Vararg parameters

Collections Fundamentals

10 patterns

Why immutable collections are default

List creation (listOf, mutableListOf)

Set creation (setOf, mutableSetOf)

Map creation (mapOf, mutableMapOf)

Accessing elements safely

Iterating collections with forEach

Mutable vs immutable interfaces

Array creation and usage

Collection size and emptiness checks

Destructuring in collection iteration

Part 2: OOP and Functional Patterns9 topics · 81 patterns

Intermediate

Lambda Expressions and Higher-Order Functions

10 patterns

Why lambdas enable functional style

Lambda syntax and declaration

It keyword for single parameter

Passing lambdas to functions

Trailing lambda convention

Higher-order function declaration

Returning functions from functions

Closures and variable capture

Function references (::functionName)

Inline functions and performance

Collection Processing

11 patterns

Why collection operations replace loops

Map transformation

Filter and filterNot

FlatMap for nested collections

GroupBy for categorization

Partition for splitting

Sorted and sortedBy

Take, drop, and chunked

Zip for combining collections

Associate for map creation

Fold and reduce operations

Scope Functions

8 patterns

Why scope functions reduce boilerplate

Let function behavior and use cases

Run function behavior and use cases

With function behavior and use cases

Apply function behavior and use cases

Also function behavior and use cases

This vs it receiver difference

Chaining scope functions

String Operations

8 patterns

Why string handling matters

String concatenation vs templates

Multiline strings with trimIndent

String methods (substring, split, trim)

String comparison (equals, compareTo)

String to number conversion

Regular expressions with Regex class

StringBuilder for performance

Classes and Objects

10 patterns

Why classes define behavior and state

Class declaration syntax

Primary constructor and init blocks

Secondary constructors

Properties with val and var

Custom getters and setters

Visibility modifiers (public, private, internal, protected)

Creating instances without new keyword

Data classes for value holders

Data class copy and destructuring

Inheritance and Interfaces

9 patterns

Why open keyword is required for inheritance

Open classes and methods

Overriding methods with override

Abstract classes and methods

Interface declaration and implementation

Interface with default implementations

Multiple interface implementation

Sealed classes for restricted hierarchies

Sealed classes with when exhaustive check

Object Declarations and Companions

8 patterns

Why object declarations create singletons

Object declaration syntax

Object expressions (anonymous objects)

Companion objects as static alternatives

Companion object with interfaces

Factory pattern with companion objects

Named companion objects

Companion vs top-level functions decision

Enums and Nested Classes

8 patterns

Why enums constrain values

Enum class declaration

Enum with properties and methods

Enum entries iteration

Enum with when exhaustive check

Inner classes and nested classes

Inner class access to outer members

Nested class independence from outer

Error Handling

9 patterns

Why error handling matters

Try-catch as an expression

Multiple catch blocks

Finally block behavior

Throw as an expression

Custom exception classes

Preconditions (require, check, error)

Result type for functional error handling

RunCatching for safe execution

Part 3: Coroutines and Advanced Kotlin10 topics · 84 patterns

Advanced

Generics

10 patterns

Why generics provide type safety

Generic class declaration

Generic function declaration

Type constraints with upper bounds

Multiple type parameters

Star projection for unknown types

Out variance (covariance)

In variance (contravariance)

Reified type parameters with inline

Generic constraints with where clause

Coroutines Fundamentals

10 patterns

Why coroutines matter for async programming

Coroutines vs threads mental model

Suspend functions concept

Launch coroutine builder

Async coroutine builder

RunBlocking for bridging

Coroutine scope and structured concurrency

Delay vs Thread.sleep

Coroutine context and dispatchers

Dispatchers.Main, IO, Default behavior

Coroutines Advanced

9 patterns

Why structured concurrency prevents leaks

Job lifecycle and cancellation

CancellationException behavior

Async and await for concurrent results

Exception handling in coroutines

SupervisorJob for independent failure

CoroutineExceptionHandler

WithContext for dispatcher switching

Timeout with withTimeout

Flow for Reactive Streams

9 patterns

Why Flow matters for async sequences

Flow builder and collect

Flow operators (map, filter, transform)

Flow context preservation

FlowOn for changing dispatcher

StateFlow for observable state

SharedFlow for event broadcasting

Combining flows (zip, combine)

Flow exception handling

Extension Functions and Properties

8 patterns

Why extensions add without modifying

Extension function syntax

Extensions on built-in types

Extension properties

Extensions resolved statically

Nullable receiver extensions

Extensions vs member functions priority

Extensions for DSL building

Delegation and Delegated Properties

7 patterns

Why delegation avoids inheritance

Class delegation with by keyword

Lazy property delegation

Observable property delegation

Custom delegated properties

Map-backed delegated properties

Delegation vs inheritance decision

Sequences and Lazy Evaluation

8 patterns

Why sequences matter for performance

Sequence creation methods

Lazy evaluation vs eager evaluation

Sequence operators (map, filter)

Terminal operations trigger execution

Sequence vs collection performance

Generating infinite sequences

When to use sequences

Type-Safe Builders and DSLs

7 patterns

Why DSLs improve readability

Lambda with receiver concept

Building blocks of type-safe builders

DSL scope control with @DslMarker

HTML builder example pattern

Configuration DSL pattern

Infix functions in DSLs

Java Interoperability

8 patterns

Why Java interop matters

Calling Java from Kotlin seamlessly

Calling Kotlin from Java

Platform types and null safety

SAM conversions for Java interfaces

Kotlin annotations for Java callers (@JvmStatic, @JvmField)

Collections interop behavior

Java streams vs Kotlin sequences

Testing in Kotlin

8 patterns

Why testing matters

JUnit with Kotlin

Kotlin test assertions

Testing coroutines with runTest

Mocking with MockK

Property-based testing concept

Test fixtures and lifecycle

Testing scope functions and lambdas

Why Leyaa

Not just a course. A learning intelligence.

Leyaa doesn't just deliver content - it understands where you are, what you need, and how to get you there fastest.

Adaptive Diagnostics

Leyaa identifies which of the 248 patterns you've mastered and which need work - before you waste time on what you already know.

Pattern-Level Precision

Every pattern gets a verdict - Learn, Practice, or Skip - so your study time goes exactly where it counts.

Intelligent Pacing

Leyaa reads your velocity across the whole course and adapts your focus list dynamically, keeping you in the optimal learning zone.

Before & After Visibility

Every assessment creates a snapshot. Retake anytime to see exactly how much you've grown - topic by topic, pattern by pattern.

Learner Autonomy

Leyaa recommends, never restricts. Override any suggestion and explore at your own pace - the system tracks everything regardless.

Clear Learning Path

Foundations → OOP and Functional Patterns → Coroutines and Advanced Kotlin - a structured journey where each part sets you up perfectly for the next.

Kotlin

Ready to master Kotlin?
Start your journey today

Start your diagnostic now. Build mastery across all 28 topics in under 15 minutes.

28 Topics

248 Patterns

Personalized roadmap

Master Kotlin with Adaptive AI.

Your Kotlin Journey in 3 Parts

Everything You'll Learn

Kotlin

Not just a course. A learning intelligence.

Ready to master Kotlin?Start your journey today

Ready to master Kotlin?
Start your journey today