Thank you so much! I think that if you download the game, you'll get the source because it's a JavaScript + P5 game.
And I, too, would love to see the code ;)
Alas, the download only contains the soundtrack - "Download" under the HTML5 brings me the same place as "Download" above the comments:
Click download now to get access to the following files:
Soft Drizzle Soundtrack 14 MB