Kotlin Professional Certificate study guide
Kotlin Professional Certificate · Work through your exam, one topic at a time.
The Kotlin Professional Certificate is a JetBrains credential aimed at developers who want to demonstrate practical Kotlin competence. According to the source material, JetBrains positions Kotlin within a broader ecosystem of tools, libraries, and integrations for building modern applications, and IntelliJ IDEA is described as the IDE for Java and Kotlin. The exam's published domains divide evenly across four areas: Kotlin language fundamentals and coding tasks; object-oriented and functional Kotlin programming; the standard library, collections, and coroutines; and tooling, testing, and IDE-based verification. That last domain reflects how JetBrains frames learning itself: the JetBrains Academy plugin lets learners work through coding tasks and custom verification tests inside JetBrains IDEs, with instant feedback and a focus on learning by doing. Topics on this exam: Kotlin language fundamentals and coding tasks, Object-oriented and functional Kotlin programming, Kotlin standard library, collections, and coroutines, and Tooling, testing, and IDE-based verification. The Kotlin Professional Certificate study guide has 4 sections and about 1,475 words.
01Kotlin language fundamentals and coding tasks
Domain 1 tests the rules you apply in short Kotlin coding tasks: declarations, nullability, control flow, equality, and numeric conversion. Questions often ask which snippet compiles or what a function returns, so read types carefully.
382 words, about 2 min02Object-oriented and functional Kotlin programming
Domain 2 tests how you design Kotlin types and compose behavior with lambdas. Expect questions on constructor mechanics, inheritance defaults, data and sealed classes, extension resolution, and higher-order functions.
368 words, about 2 min03Kotlin standard library, collections, and coroutines
Domain 3 covers standard collection operations, scope functions, and coroutine behavior. The exam tests whether you can choose the right transformation and reason about structured concurrency rather than memorize signatures.
385 words, about 2 min04Tooling, testing, and IDE-based verification
Domain 4 covers the build, test, and IDE workflow used to verify Kotlin code. Questions focus on Gradle Kotlin DSL configuration, test framework setup, coroutine testing, and interpreting IDE feedback.
340 words, about 2 min