Indie dev Matt Thorson took to Twitter yesterday to share a link to a GitHub repo containing the Player class code -- all ~5400 lines of it -- for Celeste, the mountainous platformer he and some collaborators released in January.
It's a nice way to pull back the curtain on the game's development, though as Thorson points out this is primarily of interest to anyone who played/watched Celeste and wondered how, exactly, the protagonist moves.
The game earned critical acclaim this year as a deeply challenging (and accommodating) platformer built around a relatively small moveset (jump, dash, grab), so this code dump may be a good opportunity to see how that moveset works.
In a readme file posted to the repo by fellow Celeste programmer Noel Berry, the dev team lays out plans to release a few of the Celeste class files "as a learning resource and for general interest."
For more insight into Celeste's development, check out Thorson's talk at the GDC 2017 Level Design Workshop about how the game's levels were designed and implemented, what role they play in the narrative, and how it all ties back to his love of rock climbing.