How to implement the Singleton pattern in Kotlin and what features should be considered?

In Kotlin, the Singleton pattern is implemented very simply using the object keyword. This declaration creates a class with a single instance, which is lazily initialized and thread-safe by default.

Example of Singleton implementation:

object Database {
    fun query(sql: String) {
        println("Executing query: $sql")
    }
}

// Usage
Database.query("SELECT * FROM users")

Features:

• No need to write code to control instance creation — everything is done automatically.
• Thread-safe initialization without additional synchronization.
• Can implement interfaces and inherit from classes.
• If a lazy Singleton with parameters is needed, object is not suitable, and other approaches (like by lazy) are used.

Thus, in Kotlin, Singleton is simple and safe thanks to built-in support for object."}]}]}