Advent of Code 2025 invites participants to solve coding puzzles using Kotlin during a five-day event from December 1–5, featuring daily livestreams hosted by Kotlin Developer Advocate Sebastian Aigner and special guests. The event offers an opportunity to climb leaderboards, learn new coding tricks, and win exclusive prizes for top performers and active community members who share their solutions. Participants can join the Kotlin community on Slack for discussions and hints, and they are encouraged to publish their solutions on GitHub with the topic "aoc-2025-in-kotlin" to be eligible for prize draws. The event, organized by JetBrains, aims to foster a festive atmosphere of friendly competition and collaborative learning within the Kotlin community.