Kotlin is a statically typed, cross-platform, modern programming language that grants developers expressiveness and conciseness. It allows developers to craft robust applications with improved productivity and satisfaction. As an open-source language, Kotlin is a chosen language for Android apps development, as formally recognized by Google. However, its diverse features and seamless interoperability with Java make it a versatile language for various applications including web development, server-side development, and data science.

For a professional wishing to master Kotlin, the following competencies are typically in demand:

1. Proficient understanding of Kotlin principles and how to apply them in building applications.
2. Ability to write clean, efficient, and secure Kotlin code.
3. Substantial understanding of object-oriented programming and functional programming, as Kotlin supports both paradigms.
4. Knowledge of how to adequately test, debug, and maintain the Kotlin code bases.
5. Expertise in development tools that support Kotlin, such as IntelliJ IDEA, Android Studio, and others.
6. Familiarity with libraries and frameworks that support Kotlin, such as Ktor for building asynchronous servers and clients, and Arrow for functional programming.

As Kotlin is mostly interoperable with Java, the solid foundation in Java would be instrumental in learning or mastering Kotlin. Moreover, as Kotlin also targets JavaScript, familiarity with JavaScript and related front-end technologies like HTML and CSS would be beneficial. General understanding of programming fundamentals, problem-solving skills, as well as knowledge in data structures, software architecture, and algorithms is paramount.

Professionals with a skillset in Kotlin can expect roles such as Android Developer, Backend Developer, Full Stack Developer, and more, with plenty of opportunities across industries, be it start-ups or multinational tech companies.

Thus, Kotlin represents not just an evolving language skill, but also an avenue to innovative software development and high-profile job roles in the tech sector. Cultivating a Kotlin competency could be a strategic move for professionals aiming for a strong career trajectory in Tech space.