Normal sudoku rules apply.
Within the grid lies a single snake of orthogonally connected cells which may touch itself diagonally but not orthogonally.
The first and last cell on the snake contain the digit 9.
Digits placed on circles and squares show the number of snake cells in the surrounding (up to) 9 cells including the circle or square itself if it is on the snake.
Circles contain odd digits, squares contain even digits.
Solution code: column 5
on 17. June 2023, 20:07 by Bankey
Naughty snake, indeed! Twice in the last six months, it slipped away from me, but finally i managed to catch both its head and tail on the third attempt. Thanks for the fun ride, @ Scruffamudda :). The puzzle sure deserves more solves.