To write smart contracts, Klaytn currently supports Solidity as the primary programming language. Solidity is adopted in Klaytn because it is a de facto standard contract programming language for Ethereum and has a large user base and an active community. The Klaytn team decided to provide the users with familiar development experience so that the Ethereum DApp developers could easily experiment with or migrate their existing smart contracts to Klaytn.
In the future, Klaytn also plans to support writing smart contracts using other programming languages. The Klaytn team is investigating various favorable programming languages that developers might embrace.