Several archival-focused Yandere Simulator communities exist on Discord. They maintain "museum channels" with verified hashes of old builds. This is the safest method, as members run checksums to ensure the .exe hasn't been tampered with.
: The Internet Archive (archive.org) is a digital library that provides access to a wide range of software, including old video games. You might find archived versions of Yandere Simulator from 2015 here.
Exploring the Past: How to Find and Play Yandere Simulator 2015 Old Builds
